Sciencemadness Discussion Board - Preparation of elemental phosphorus

It is nice to see someone experimenting again. Please be careful. "In my bathroom..." (shudder)

What is NAPO4? Do you mean Na3PO4? Most of my work was done with NaPO3 (FYI).

Magpie! Thank you for the well deserved warning. You might shudder more if you knew I work with chemical and biological (mostly bio) toxins for a living. So I'm NIOSH, AIHA, IAQA NAETI, ESA, etc certified.

The issue is we (me and my brother) store all our zip walls, tychem suits, survivair, negative air machines, etc at my brothers new house.

Then also I moved to the marketing side of the business 4 years ago. So I really don't work with hazardous materials as much as I use to.

And yes, it's NaPO3. I keep mixing that up with the PO4 from TSP which is what I started with. Then I moved to TCP and now I only use the hexameta.

While I'm on the topic of SAFETY I'd like to say 1 thing about phosphine which *may* help a few broke souls. And before I do please keep in mind I am NOT recommending anyone does this. I'm qualified to advise on certain industrial air scrubbers. But I am NOT qualified to recommend anyone alters their respirators (assuming you use one).

With that said, this is one of my custom masks that I've personally been using over 6 years. I've shown it to toxicologists, industrial hygienists, air quality consultants... they warned me about the seal but the seal always works when done right. And the benefit of this mask is:

1) It scrubs significantly more air, debree & toxins than the $25 refill cartridges that have to be replaced literally every other time you use them. Even if you're doing something as simple as painting you'll notice those cartridges go bad after about 16-24 hours of use.

2) When I started out there were many times I'd get sore throats or headaches from the silver encapsulants or other chemicals we were using. This mask stopped that. I never got a sore throat or headache again.

3) There's been a few times I've accidentally been exposed cause I thought my cartridge was still good. Or because the previous lab did the wrong tests (or not enough tests). Then I'd wind up in bed sick as hell for days sometimes weeks. Only one time have I been to the ER and that was one of the scariest feelings in the world.

Generally speaking most our cases are low to medium risk. So most the time I didn't wanna work in a bulky tychem suit or use a full face respirator. I'd opt instead for a hooded tyvek suit and the respirator I'm gonna show now. In more serious cases I'd def opt for something like tychem.

But this is my point. Over the years I noticed a serious problem where in most low-medium risk cases.... so many people, even qualified people would sacrifice their health cause it was A) more comfortable or B) more affordable. Like after Hurricane Katrina. OSHA changed their guidelines to allow the use of cheap n-95 masks to protect workers from toxic mold exposure. Tons of workers wound up sick. 9-11.... I won't even get into that.

So let me get to the point. This mask is filthy and I usually clean it with alcohol so it looks nice and new.

But these are the masks you're likely to find at Lowes or Home Depot:

The only difference is they don't come with those huge black custom made scrubbers on the end.

They come like this. Look at the right of the mask not the black piece. That little screen looking thing is the cartridge they provide you with that you're suppose to replace.

Now I turned the "custom scrubber" upside down. You see polyester fiber. Under that fiber is A LOT of activated carbon. Then another layer of fiber on the other side.

I flipped it over. So you see a thin plastic screen with vent holes and the fiber underneath.

People may be looking at this and thinking "I'm not building a custom scrubber are you crazy?"

But that big black rubber scrubber piece.... both Lowes and Home Depot SELL THEM right in the gutter aisle. They're about $6 each and they're all the same size. Buy 2. I accidentally figured out that the large end fits PERFECTLY, like a glove, right over the cartridge that's ALREADY ON the respirator. This way you're not actually "altering" anything. You're not breaking, removing or doing anything to the original cartridge that comes with the mask.

All I did after that was simple:

1) Cut plastic circles (any flat, thin, plastic material works). The piece just lays in. I drilled a bunch of small holes in that plastic then permanently epoxied it to the rubber.

2) I packed a nice big wad of polyester fiber.

3) I pour dry activated charcoal (fish tank stuff) onto a metal strainer, shake over a garbage can to get the dust out. Then put a whole bunch in the mask. Around 1/2 - 3/4 cup.

4) Pack another layer of fiber to sandwich in the charcoal (fish stores sell the fiber).

5) After that you slip the whole thing on tight. Then what I personally do is clean the edges with alcohol and tape it to the bottom edge of the cartridge with black electric tape. It creates a super tight seal cause you can't breath if you put your hands over the black scrubbers.

Now here is what I do for PHOSPHINE.

Very simple. Do the mask as I listed before. Except you need copper sulfate. Create a saturated solution. Pull off the top fiber then spray it on the coal so it's "moist". I do 1 spray, mix the coal, another, usually just 3-4 sprays till it looks black and moist. The fiber should stay white otherwise you used too much. Then let the outer C dry a tiny bit, throw the fiber back on and reseal it.

This is how phosphine scrubbers are built: http://ftic.co.il/2000FresnoPDF/83.pdf

It may seem crude but I love this mask. It's designed to scrub a lot of air, it lasts for months, the original cartridges only get dirty maybe once or twice a year. But more importantly for phosphine, studies show you need MOIST charcoal with copper sulfate to properly scrub.

When you're done using it throw it in 3 plastic bags sealed tight to keep the moisture in. If it dries just add some water. AFA how long to use? That's too relative. But I'd say it's good for a lot of cooks if you store it properly.

I wouldn't step into a room full of phosphine with a mask like that. But for homemade quantities of P4 I feel 100xs safer using that mask then my survivair or what comes off the shelf at Lowes or Home Depot. In the end everyone should have great ventilation. A fumehood or airscrubber. And I'll be picking up a mini air scrubber from my brother but I'll still be using this mask. Even if I was doing this outdoors so many people have died from aluminum phosphide / phosphine fumigants that countries are banning them.

Everyone please stay safe. =]

Magpie - 16-2-2016 at 09:08

My safety concern was meant more for skin burns. At least two of our members have experienced painful phosphorus burns. It is especially enlightening to read the story told by rogermeryaw. He had to go to the hospital for liver damage.

I also consider white P to be a serious fire hazard. I converted all of mine to PCl5 for that reason.

I appreciate the information you have given us on using PPE. I have a powerful fume hood and don't use a mask. If I felt I also needed a mask I would likely not do the experiment.

The small amount of phosphine I have generated during my experiments seems to quickly burn off with small pops and flashes of light.

BluePlanet1 - 16-2-2016 at 23:54

My safety concern was meant more for skin burns. At least two of our members have experienced painful phosphorus burns. It is especially enlightening to read the story told by rogermeryaw. He had to go to the hospital for liver damage.

I also consider white P to be a serious fire hazard. I converted all of mine to PCl5 for that reason.

I appreciate the information you have given us on using PPE. I have a powerful fume hood and don't use a mask. If I felt I also needed a mask I would likely not do the experiment.

The small amount of phosphine I have generated during my experiments seems to quickly burn off with small pops and flashes of light.

Interesting. I recall his post about phosphorous being a "backstabbing bitch" but nothing about the hospital or liver damage. Very scary stuff. I can only hope that he (and the other member) were not touching it with their hands.

With me, I'm not that worried about the fire hazard. That's post production I should say.

My biggest fear is the phosphine. And it's because of how I was introduced to this reaction roughly 6 months ago. A book called "General Chemistry" by Linus Pauling. Published 1970, 945pgs big. In the entire book, there were only 5 short lines about making WP:

"Elementary phosphorous is made by heating calcium phostphate with silica and carbon in an electric furnace. The silica forms calcium silicate, displacing tetraphosphorous decoxide, P4O10, which is then reduced by the carbon. The phosphorous leaves the furnace as vapor, and is condensed under water to white phosphorous".

That was it. So I went online... was researching for hours & never saw this thread. I never saw Rogers video cause it wasn't keyword optimized. I saw Red Niles channel. Very smart guy. So I asked him if he ever tried this synth and he said "no, but if you succeed please message me."

So I mixed TSP with damprid in saturated solutions. Boiled them. The whole thing solidified. I assumed that was pure TCP, washed, filtered & dried.

I mixed that with silica and carbon then applied pure HHO to it. Just to "observe" if anything would happen doing this in open air. 3-4 minutes later that mixture lit up like a star ... within seconds my whole house was just plumes of smoke so I grabbed my dog and threw her in the backyard. Run back in coughing, choking, eyes watering, my throat was burning like I ate a ghost pepper. I'm plugging in fans, opening windows, worried about neighbors... wondering where my gas mask is.... 2 mins later I had to go outside. Then took my dog for a long walk.

As I was walking my dog towards the beach I didn't feel right. My throat was better but my heart was palpitating in a very weird and noticeable way. I was hitting my chest with my hands. I felt flush but cold. My nerves felt "tazed" in a weird way. Like a low current of electricity was going through my body it felt really weird. And IDK what caused that reaction I just know it was something in the air.

When I later found this thread and read about phosphine that's when I became phosphine-phobic. Because P4O10.... afaik... it's not that toxic. It's toxic in a tear gas type of way but not in a "let me hijack your nervous system & try to kill you" type of way.

There's a side of my brain that says "that reaction was too hot for phosphine and had no AL." It was hot enough to sublime all that carbon in a matter of seconds and looked a bit like plasma.

Then I thought.... "what if the free hydrogen from the HHO was combining directly with the phosphorous?" The same way H2 from HHO embrittles steel at high temperatures.

The larger more current reactions I've run I can see PH3 popping and exploding in the water. So it seems like most of it burns right up. At the same time, how do we even know that's PH3 exploding and not P2 vapor hitting the air? Both burn orange. Maybe it's a mixture of both. And maybe P2 vapor can steal the oxygen PH3 might use... then blow that out into the air. So it diffuses before it can burn.

Anyway, none of this ranting will matter when I pick up my air scrubber. The weather is also warming this week which is great. Pyro MG should be here tomorrow. I'm may increase the amount of MG/C for trial 3 on camera. Hopefully be ready in a few days.

BluePlanet1 - 7-3-2016 at 02:48

Hello all,

Just letting the forum know that I haven't disappeared. I've been plundering the depths of Lowes, Home Depot, Harbor Freight... bought an arc welder... grinder.... tried to teach myself to weld and many other things.

One of the hardest parts of making P4 is the "plumbing" on this final device. It was me trying to matchmake pieces for hours. I asked and spoke to tons of employees. None were plumbers or welders. So I taught myself about welding, plumbing, compression fiitting, threads, etc.

The new retort I made is very simple but interesting. It's 2 pieces of steel and 4 pieces of brass. You can buy everything at Lowes. I will get pictures and a video up soon.

The best part about this new retort is it's HIGHLY scalable. You can easily increase the amount of P4 just by having enough air-propane torches or 1 single good air-propane torch to drive a lot of air-propane at the main pipe. That would heat up hot as hell and distill into a middle pipe, where it collects on the surfaces, then the water.

Afterwards I can turn the heat up on the "predistiller" to drive the rest slowly into the water.

I like this idea of using pipes instead of cans to make WP. And to be fueled by a jet of air propane. I have 4 air-propane torches which should be enough when I begin to scale. All 4 turned into the same direction create a miserably hot center of focus. But next I'm just buying a large propane tank. And I may divide all 4 heads to disperse them around the furnace.

I may wind up building a mini industrial WP machine. One big propane tank would be plenty. I have to do this.

[Edited on 7-3-2016 by BluePlanet1]

Magpie - 7-3-2016 at 09:32

I am looking forward to seeing your new P making device and your video!

I don't like cans especially either although I found them practical for one reason: they're cheap and therefore disposable. With the standard recipe using NaPO3, Al, and SiO2 there is a lot of nasty slag formed in the retort. Removing this slag was both tough and hazardous due to traces of P. With the cheap can I can avoid this step by simply disposing of the can w/slag as a unit.

How easy is it going to be to clean out your retort? If you make a large, labor intensive, and costly retort you are going to want to use it more than once, right?

Daffodile - 7-3-2016 at 12:28

I am looking forward to seeing your new P making device and your video!

I don't like cans especially either although I found them practical for one reason: they're cheap and therefore disposable. With the standard recipe using NaPO3, Al, and SiO2 there is a lot of nasty slag formed in the retort. Removing this slag was both tough and hazardous due to traces of P. With the cheap can I can avoid this step by simply disposing of the can w/slag as a unit.

How easy is it going to be to clean out your retort? If you make a large, labor intensive, and costly retort you are going to want to use it more than once, right?

I'm trying to make a retort from an encap, pipe, reducer fitting, another pipe, and a bent tube, all made of copper. That way, the residue may be able to be cleaned out with acid. As well, the fittings are fitted well enough, so apart from traces of metal glue, I won't have to weld or whack anything.
This solves a lot of problems.

BluePlanet1 - 13-3-2016 at 15:59

THIS IS MAKING ME FURIOUS! I swear to god I'm losing my mind with this P4 crap.

I don't know why I'm so stuck on trying to make this experiment "epic". I just know I've made A LOT of dangerous and challenging compounds in my life. I've made organic compounds that from a chemical technical standpoint are 100 times harder to synthesize.

But this stupid "simple" reaction, a reaction that's so EASY from a chemistry standpoint is still an engineering NIGHTMARE.

*******************

A few hours ago I tested what's suppose to be my *final* design. I spent weeks (really months) putting this together and thinking through every aspect of what could go wrong. Yet the only epic thing that happened was how horribly it failed.

And I PROMISE I'll get pics up. I had both my camera and phone nearby but I was wasting too much time trying to get the right angle. The table I work on (it's a metal sheet) slips over the bathroom sink. Then I clamp it to the sides of the sink, put together my stand & retort... you'll see pictures. The problem is I have to film from the left where the reaction happens but there's a wall 18"-24" to the left. If I film from the right people won't see the distiller side where the P4 comes out. What I need are 2 big suction cups (ShopRite has them) and I'll hang the camera from the ceiling to get the perfect angle. It's just too dangerous right now trying to play with a camera and 2 torches with my current midget tripod.

Pic's will be up soon though since I need help. And YES I'm still working in the bathroom for various reasons:

1) I "upgraded" my ventilation. All I really did was clean it out from the attic. I noticed it was clogged with insulation. I cleaned the insulation out then put another fan in the attic so when both are turned on it draws up air REALLY FAST.

2) The bathroom walls are mostly tiles. IDKY I just feel safer with tiles cause they're denser and can be cleaned real easy.

3) I have 2 areas I section off with drop cloth. It stops any fumes from going into the laundry room and helps direct them towards the vent.

ALSO. I made a "phosphine detector" by turning my flood lights on and trapping a bunch of moths, flies, etc with a fishnet. Then I put them in tubberware and ductaped a screen over the top. I figured since phosphine is a POWERFUL fumigant.... if the insects don't die being within 12" of the reaction then I'm good with my respirator on. And for the record, with all the gas that did escape I'm pretty convinced this reaction does NOT put out very much PH3 at all. Which is basically what Magpie was saying.

It may sound twisted but I'm going to use an insect detector like this on my next few cooks as well. I kept them in the container for like 3 hours now and just let them go. They were all fluttering perfectly healthy and went back home. :-)

*******************

SOOO THIS IS THE PROBLEM!

I setup everything beautifully. I was sure to wrap up everything real good with plumbers tape. I filled the retort then taped and screwed the last piece on. Then I firmly but tightly tightened everything with a wrench.

Now HERE is what's driving me INSANE. Prior to loading the retort I noticed the distiller end happened to fit perfectly inside an electric tire pump (like 1/4" hole). So JUST TO CHECK I turned the pump on, held the distiller under water upside down then PRESSURIZED the whole unit. I was throwing the pressure in this device over 60PSI and **DID NOT SEE 1 BUBBLE** escape under water. This thing was AIR TIGHT.

That gave me the greenflag to go ahead. And just a sidenote I did NOT attempt to "seal" the threads with fine SiO2 powder. I was worried it could screw up the seals so this time I just used more teflon and wrenched it on tighter.

I turn on both my air-MAP torches. I begin to preheat for 2-3 mins as bubbles slowly draw out of the distiller.

After 2-3 mins I turned the heat up slightly. I started to see beautiful plumes of stringy smoke erupting as the bubbles hit the surface of the water. I kept it going very low heat and witnessed NO explosions of phosphine. THEN I maxed out the flames on both torches.

Within 30 seconds I saw a FLOOD of reddish white flakey mud pouring out of the distiller. Which didn't happen last time. Last time I got pure white clumps of wax I didn't even notice when they formed. But last time the P4 also sunk to the bottom. This time for whatever reason it kept trying to float to the top. I believe the water MIGHT have been too cold? IDK. Or something else was going on but pictures will show what I collected.

Then suddenly 3 small clumps of aluminum colored SLAG rifled out of the distiller and sank straight to the bottom like stones. I thought "what the hell I didn't even fill the retort half way?" so I immediately turned down the heat just to see if bubbles were still coming out which they were.

I assumed there was no clog and turned the heat back up. Bubbles came out a few more seconds then suddenly stopped. I noticed all the teflon tape on the pipes was gone by now. I started watching those seals. Sure enough I notice little blue speckles of fire around them. Then those small blue speckles turned to big white balls of molten phosphorus fire which ignited on BOTH ENDS OF THE PIPE!!!

This breach was WORSE than the 1 time I tried using no plumbers tape at all. I was soooo f#$kn mad & confused. And maybe I have a death wish but I refused to stop cooking. Instead I turned the heat back up full blast just to see how bad it would get or if anything else would breach.

The P4 continued to burn in huge balls of fire all around the seals of the pipe. After 10 minutes of just watching all this P4 burn up I thought "damn, that could have been such a nice yield" then turned the fire off as WP still burned.

Eventually the fire on the seals went out. Then I pulled the distiller out the water so there was no pullback. And now I see the opening of the distiller is burning this very calm, blue flame. I look up inside the pipe the hole thing is lit up with that trademark blue flame.

So I tried sealing the distiller like I did last time (plugging it with wet cotton) and it wasn't working. I believe because last time I did this we had a snow storm. It was freezing cold in the bathroom which helped cool down the pipes faster. This time the pipes stayed hot as heck. The P4 was now solidifying on the cotton. Then suddenly I felt little needle stings on my hands going through my WELDING GLOVES.

At first I didn't even realize what was happening. But the P4 was going through the cotton, getting onto the gloves, it would dry out then burn these micro sized needle holes through the gloves. It felt like a bunch of green flies stinging my hands. So now I had nothing to hold the wet cotton on. I took off my gloves immediately. The distiller caught blue fire again. I got my wrenches instead. Went through all sorts of crap spraying the retort with cold water then wrapping it in bags as it burned through the first 2 bags then I just wrapped the hole thing in foil and finally I was able to vacuum seal it in a ziplock bag.

WHAT A MESS.

After this happened I gotta admit I wanted to just drop everything and quit. But now I'm anxious, pissed off, I'm more obsessed than ever to make this work.

Here are some key things I discovered:

1) Even though the brass side of the unit got extremely hot and lost PTFE tape (closer to the top)... none of those brass pipes breached at any of the seals. This really goes to prove that brass compression fittings, even when the PTFE melts or vaporizes off, the pipes alone are fully capable of keeping P4 sealed within.

2) Steel NPT pipe has got me at the end of my wits. I'm just completely out of ideas as to HOW I can make a seal with these pipes and threads. It seems the threads are too wide, too deep, too steeply tapered, no matter what they can't and won't lock vaporous P4 in at 1100C.

3) The unpredictable question of "what happens to steel NPT threads at that high a temperature"? With brass, cause the fittings are so tight and deep you have at least 5-6 threads locked in tight. So even if the metal expands during heating... those threads are so tight they hold up no matter what. With steel NPT, it's only 2-3 threads creating the "seal". Plus the threads are bigger and loser. It's possible that the steel is expanding enough for the P4 to get through the 1st thread which is the technically the tightest (due to the taper). Then once it gets through that 1st thread, the last 2 are a bit looser from the taper so it becomes effortless for P4 to breach it.

What are possible solutions? This is what I really need help with and I'll get photos up in a couple hours.

The way I see I can...

1) Permanently weld the capped side on. I like to take off the capped end just cause it's easier to clean. But all I need is 1 opening to quickly clean the pipe. So if I permanently MIG weld that cap it would fix 50% of the problem. The problem is it defeats my goal of building a repeatable, scalable system that any amateur chemist can easily replicate.

2) Even if I weld that 1 end I can't weld the part that connects to the elbow. So welding really isn't an option.

3) These threads NEED to be modified or sealed in a really creative way. This is the only real answer I see I just have no real answer to it.

You can't do compression fitting on steel it only works on brass since it's soft. I'm not welding. I'm not custom threading the pipes.

Looking at this logically I have 2 things to try.

First is trying a homemade SiO2 "glue". I was gonna try this before it may be time to try now. Where I mix a pinch of dextrin with super fine SiO2 powder. Paint it on the threads, seal then heat. If P4 gets through the threads it will need to move through the SiO2 which would be impossible only IF the SiO2 gets properly compressed in the threads air tight.

If that fails, I may try using a hacksaw or my grinder/cutter to cut the last 3 threads off each end of the pipe. IDKY. I just know those last 3 threads hang down inside the pipe, they're the loosest threads, maybe that might may a better seal although I'm skeptical.

It's gonna have to be some homemade high temperature glue. This would be so much easier if Lowes or Home Depot simply sold high temperature plumbers tape but I checked and they don't. The more expensive plumbers tape is made of the same PTFE material. If they simply sold real teflon wrap that would not vaporize or breech.

Either way I've done enough ranting. Let me go take some pics so I can show you people what I'm working with.

ps. Magpie, the retort is very easy to clean out when it works. I just drill a hole through the middle of the slag then bang it out with a flathead screwdriver. Usually take 2-3 mins to clean out.

pss. To Daffodile, it sounds like you may be using a similar design as I am. I don't believe you're gonna have luck using copper or brass directly to cook in (it can work on the cooler sides of the device to distill) but if you've tested anything please let us know.

[Edited on 14-3-2016 by BluePlanet1]

Magpie - 13-3-2016 at 16:31

I'll likely comment more after I see your pictures but here's some for now:

1. I'm worried that you are not showing enough respect for white P. If you felt pain through your welding gloves something is very wrong.

2. How can you expect ptfe joint tape to hold up to the high temperatures needed to make phosphorus. It's only good to 250-300°C max, and then for a short period.

3. NPT threads of steel/iron pipe don't form a very good compression seal. You need some kind of pipe dope (sealant) even for water. Eventually in water pipe corrosion forms the seal.

4. Furnace cement might provide a suitable sealant. Whether you can then break/clean the seal later I don't know.

5. It is encouraging that you consider your device easily cleanable. It seems like drilling and pounding on the clinker would put phosphorus containing dust in the air. Wearing a dust mask seems appropriate.

------------------------------

6. Something I've never tried due to cost but might work well:

Use bolted flanged joints. There's high temperature gasket material available: link

[Edited on 14-3-2016 by Magpie]

[Edited on 14-3-2016 by Magpie]

[Edited on 14-3-2016 by Magpie]

[Edited on 14-3-2016 by Magpie]

blogfast25 - 13-3-2016 at 18:31

6. Something I've never tried due to cost but might work well:

Use bolted flanged joints. There's high temperature gasket material available: link

While some of these materials may have the requisite temperature resistance, will they have significant sealant power (elasticity, basically)?

And how about chemical resistance to high T WP???

[Edited on 14-3-2016 by blogfast25]

BluePlanet1 - 13-3-2016 at 18:35

Ok lets get some photos up.

This is what the retort and distiller looks like. 4 brass pieces + 2 steel pieces + the steel compression ring.

You can kinda see here where the P4 burned up on the threads. There use to be teflon on those pipes now there's nothing.

This is a picture of the crud that came out. It wasn't quite as red a few hours ago but does smoke and catch fire when dried.

Just another angle. My last batch delivered pure white yellow and SOLID pieces of wax that "magically" appeared at the bottom. The only difference was I used room temp water back then and my old distiller which I posted pics of weeks back. I also used a lower charge in the retort.

This is the bigger retort that can connect to the smaller one for bigger charges.

This shows the slag when it overcooked and shot out the distiller rather violently. I don't know why but I feel like this is what made it so red. As I've never had a slag blow over like this and have also never had my P4 look like gold fish flakes.

This is a closeup of the 4 brass pieces you can buy at Lowes. There was no breach on any of the brass except the brass to steel connection and steel to steel connection. And yes, it took me WEEKS just to build this stupid (but effective) distiller.

I was trying to recook so see if I could get WP to breach on the steel area which it did not. There wasn't enough left to recook. But you can see smoke coming out the distiller.

More smoke...

One more...

Now the P4 in the distiller ignites and smoke starts to travel upwards...

I tried to catch a phosphine burst here but it was too quick (you can't see anything)..

After I dumped the distiller in water I turned the lights out.

I was gonna take another pic of my previous P4 runs but I have less than half gm left. It's nothing spectacular just 2 small waxy yellow clumps.

Overall I'm not sure why it came out so red this time. It could have been from the breach and overcook as I did turn the heat up real fast once it was dry. I just know I need a way to effectively seal these steel threads before I can video tape anything worth seeing. There are SO MANY tests I've love to do. Varying ratios of all sorts of mixes then measuring yields. So tomorrow I'll try making my homemade SiO2 glue. I doubt it will work but I'm gonna experiment with everything until I find something that can stop these annoying breaches.

It's also weird that I only filled the pipe about 1/3 with powder. But when I unscrewed it the slag had expanded past the elbow and into the top of the distiller which I banged out with a screw driver.

The last time I cooked I used the same exact mix just a bit less. And when I unscrewed the pipe then more than half the whole pipe was empty. So it seems like the slag only expands if you overheat as it goes off... which I did. Then obviously if you remove the heat too fast it will freeze in that form. On the other hand if you remove the heat as it starts cooking (then slowly reapply) the slag doesn't expand. The only reason I didn't remove the heat I was afraid it might pull water back into the pipe.

At least I know not to do that again. ;-)

edit: Magpie just saw your post. You are spot on about everything. The only reason I thought the tape might hold up was because it was under pressure. But clearly I won't be using the tape anymore I need a much better sealant.

edit: Just saw the link I appreciate that. I never heard of those fabrics before but that def looks like something I might be able to work with. TY!

[Edited on 14-3-2016 by BluePlanet1]

Magpie - 13-3-2016 at 19:09

Thanks for the pictures! The safety razor in the background is a nice touch. In case everything goes to hell you can always slit your wrists!

Some more comments:

1. The reason the ptfe is not failing on the brass tailpipe is that it is considerably cooler that the steel pieces.

2. Waterglass (sodium silicate, a liquid) is a good furnace cement, apparently. I was told this by a foundry worker. It is available from some pottery material suppliers:link. But this might lock those threads tight.

3. You probably know that furnace cement is available at Ace hardware.

@blogfast

I agree that not every high temperature material on that link will likely be suitable. I would would first try those that have low porosity. The ceramic paper might work.

At first I thought Garlock's graphite or ss/graphite (Flexseal) gaskets might work but their best "high temperature" gasket was only rated to 538°C.

blogfast25 - 13-3-2016 at 19:23

@BluePlanet1:

I think you're over-cooking though. Somewhere much higher up in this thread an experiment of mine with that reaction showed that it needed relatively little outside heat, to keep going at a gentle pace.

That could explain the extreme slag expansion you seem to be experiencing.

[Edited on 14-3-2016 by blogfast25]

BluePlanet1 - 13-3-2016 at 20:20

OMG I was laughing so hard when I read that razor comment! Hilarious.

I did some research to see what material these factories are using to bind ceramic, silica, graphite, etc to thin papers. Then I just typed in "high temperature binders" into Google and the first page that popped up was some company selling a bottle of potassium silicate.

Then I came back here and read Magpies comment on the water glass stuff. Then I went to wiki and noticed you can make it with KOH and SiO2 at 90C.

This is GREAT NEWS as I have lbs of KOH that I use as an electrolyte for my HHO torch. Apparently I just have to mix it with silica and I can use this stuff as a binder with other high temperature powders like ceramic, graphite, etc. I'm so excited right now this is AWESOME! Just hope it works.

And blogfast I think you are right about overcooking. There is really no need for 2 torches on a pipe this small lol.

I'm so glad I found this forum. I feel like I'm on the right path now and will update as things progress.

THANK YOU ALL I'll be back soon. :-)

blogfast25 - 14-3-2016 at 09:01

And blogfast I think you are right about overcooking. There is really no need for 2 torches on a pipe this small lol.

Yes. But continued external heat is nonetheless needed.

2 NaPO₃ +10/3 Al + SiO₂ ===> 1/2 P₄(g) + 5/3 Al₂O₃ + Na₂SiO₃

... is by my evaluation mildly endothermic, so it works by distilling off the P₄ vapours.

But one can see how too fast evolution of P₄ vapours due to over heating could lead to slag foaming.

[Edited on 14-3-2016 by blogfast25]

Magpie - 14-3-2016 at 10:02

I had a thought that a lower melting reductant than aluminum (mp=660°C) might work to our advantage. Zn has a melting point of 420°C. I can't remember if anyone has tried this?

-------------------------------------------
If I was to do any more experimenting in this area I would first decide what size and shape reactor I wanted for significant lab scale production, say 25g of white P per run. Then I would build an electric furnace using Doug's method as shown here: Doug's Lab furnace. This looks like an extremely simple, quick, and cheap way to build a specific purpose furnace.

-------------------------------------------------
I looked in BromicAcid's phosphorus summary in Prepublication for any Zn reductant results. He cites an old reference describing the use of Zn. But there doesn't seem to be any work reported by SM members.

[Edited on 14-3-2016 by Magpie]

[Edited on 15-3-2016 by Magpie]

BluePlanet1 - 14-3-2016 at 20:12

Magpie I must say you are a life savor. I made a batch of concentrated sodium silicate solution today and this stuff is incredible. I chose NaOH over KOH simply because that's what YT videos were using.

At first I doubted it would have any real adhesive abilities. Then I painted some on a piece of steel. I fired it up and this stuff sticks like super glue. Another interesting property is as water is driven out the material EXPANDS. Almost like a glassy type of styrofoam. Then as the rest of the water is driven out it collapses back into a pure solid. Like a very hard, non-porous type of glass.

I was also researching as I was playing with this stuff and it says right in wiki: "When mixed with finely divided mineral powders, such as vermiculite dust (which is common scrap from the exfoliation process), one can produce high temperature adhesives." https://en.wikipedia.org/wiki/Sodium_silicate#Refractory_use

So I grinded some SiO2 super fine with a mortal and pestle. Mixed them together, in this form (with far less water and Na2SiO3) it fires with minimal expansion then creates a crazy strong seal. Best of all the seal can be broke by dumping it under water.

As a mere suggestion, I'd say ANYONE trying to make P4 should start by preparing their own batch of Na2SiO3. If I knew about this stuff before it would have saved SO MUCH TIME trying to perfectly fit pipes together. You can make crucibles with this stuff... repair holes, breaches... it's like it was made for this reaction. And I must say, I'm yet to actually test it with white phosphorus. But if you can use this as a binder to build non-porous retorts, crucibles that hold molten iron, high temp furnaces.. I'm very confident it will work for my needs.

As far as Zinc I'll test anything in small amounts then scaled as needed. I already planned on doing mixtures of AL/C/MG so Zinc should be no problem.

The only thing I need to do is build up my supply of SiO2 dust. The blender can get it real fine but I don't have a proper mesh for screening so I'm going to grind down like 50 more gms of SiO2 with my hands. Just for easy access as I'm running future tests.

And last, if my next cook passes the breach test which I'm confident it will... then finally I can get the camera out and start rapid firing as many differnt mixes/ratios/yields as possible. I'm gonna beat this horse dead till I understand this reaction like I understand the back of my hands!

BluePlanet1 - 17-3-2016 at 17:13

OK!!!

Did a small scale breach test run and the sodium silicate was a SUCCESS!

I may or may not do pics later (bit busy right now) I just wanted to update so others know.

To prepare the Na2SiO3 I just mixed 40gms NaOH + 60gms SiO2. Then 100ml of distilled water. This was boiled in a stainless steel pot which I prewashed with hot lye solution just to make sure it was clean.

The first time I prepared sodium silicate it took almost **45 mins** just to dissolve the beaded SiO2.
So on my 2nd run I changed 2 things:

1) Powdered the beads. Do yourself a favor and don't skip this step. It saves lots of time.
2) I used 120ml of distilled water (1/2 cup exactly) as that extra water helps the reaction go faster and you're gonna boil it off either way.

I also made a small scratch in the pot at the level of the water which helps gauge when you need to replete with water.

Don't be afraid to use an excess of water at first. It helps the NaOH dissolve the powdered SiO2 much faster. My second run took a bit less than 20 mins.

---- How I Made My "High Temperature Adhesive"-----

It's really simple. You just grind down SiO2 really really fine with a mortar and pestle. You'll know when it's a "dust" just by the way it cakes and compresses when you stir it with the grinder. Plus towards the end of grinding you can feel there's nothing left to crush. Make sure you wear a n-95 mask too.

Also, I experimented with mixing SiO2 dust with a very small amount of talc (baby powder/magnesium silicate). I was thinking "since talc is soft, used as a lubricant and anticaking agent maybe it'll help the final paste spread better." I WAS WRONG! Do not adulterate the silica dust with any talc. There are guys who line their forges with a mixture like this. For binding to vermiculite. They also add a bit of plaster of paris too which I didn't do.

But what I found is the talc completely screws up the the pastes ability to bind to metal. It doesn't spread or stick anything like pure silica does.

All you do is pour the silica dust into your FINAL STORAGE BOTTLE. You don't wanna be transferring this paste much after you make it (it's very sticky).

After I put the silica dust in I SLOWLY added the 99% concentrated sodium silicate solution. Then I stirred it really good. Then you add a bit more. Stir really good. Keep adding the "water glass" till it turns into a real thick paste. It will take on a thick but pourable viscosity like honey. You COULD add more water to make it thinner but keep in mind the more water you use the more it expands. That's why I like the paste as thick as possible.

After you make this paste you can SEAL ANYTHING WITH IT. I tested it on copper, brass and steel. It binds excellently to all 3.

And let me add a few notes about curing it. If you cure it with a propane torch the mixture WILL expand. But it does NOT get porous. It creates a complete seal so no air can get through.

The other way to cure it is to simply paint it on then leave it. After 3-4 hours it'll turn solid to the touch. Very hard. But it'll still have moisture so you probably want it to sit at least a day. The only good thing about curing with air is it doesn't expand.

The points on my brass distiller where I originally used PTFE tape I let those areas air cure. Technically it still had water in it when I cooked. But the slightest bit of heat during the reaction immediately cures it. It's really cool stuff in the respect that even if some hot air "leaks" (with vaporous WP)... the second it hits this stuff it locks up keeps everything inside the chamber.

For the steel threads I painted on a VERY SMALL AMOUNT. By "small" I mean I literally just painted this paste to fill the recesses of the threads. I did't put huge globs over the whole pipe cause I was worried it might expand too much and damage the threads.

That's something I can't stress enough. You only need a real small amount of this stuff to lock the threads up. And to lock the threads I paint it on 1 end first. I heat that end up to cure it (just 2-3 mins of heat). THEN I fill it with my reactants. After it's charged I paint the other side. Then I tighten it on with my hands (no wrench). Before I start the reaction I just aim the torch at the end that doesn't have the powder. And I cure that end a bit slower with a bit less heat for 4-5 mins. This way it cures at lower heat without the powder reacting. And TBO even if the powder did go off I see no way how it could get through this paste. It just locks up and hardens so fast. I was also watching for any extra phosphine and didn't see anything abnormal.

Finally, when the reaction is done you can dump the whole thing in hot water outside. That will get into the threads and unlock it. What I did instead (to save the external seals on the distiller) was hit it with a hammer then wrench it off like superman. It was a serious PITA. Next time I'm just dumping the whole thing in water cause I'm gonna destroy the threads if I do that again.

That's about it for now. I just proxied my YT account today so I'll be moving to video after this. And I also gotta order some Zinc from ebay.

Be back soon,

-BP

Magpie - 17-3-2016 at 18:07

OK!!!

Did a small scale breach test run and the sodium silicate was a SUCCESS!.....

That's about it for now. I just proxied my YT account today so I'll be moving to video after this. And I also gotta order some Zinc from ebay.

That's really good news. Thanks for the details on making the cement.

About the use of zinc as reductant: I went back into this thread to see what I could find out about the use of zinc. I didn't find much except someone stated that this would form zinc phosphide. That would be bad news! Phosphides react with water to make phosphine which is highly poisonous. So I have to retract my suggestion to try it. It should only be tried if you are fully prepared for the production of a considerable amount of phosphide/phosphine. I would only try it on a very small scale with excellent ventilation, ie, a powerful fume hood.

BluePlanet1 - 18-3-2016 at 01:01

Ok, I just had to try since this is such a mystery.

I just made 1.1gm crude zinc powder from 97.5% zinc pennies. It had a bit of copper but at that % I figured why not?

I used 6.8gm NaPO3 + 1.6gm SiO2 that are used for the Al reduction. Ground as fine as baby powder. Then mixed 2.8gm of those reactants with 1.1gm of crude zinc. The zinc powder was a bit coarse, but still mixed very thoroughly.

All I wanted to see is what would happen when cooked in open ventilated air like I've done with Al before.

I held the mixture over my propane torch.... waited.... waited... everything got bright orange... nothing was happening... then suddenly I see a couple of blue sparks with white smoke. Characteristic zinc burning in air. Immediately after those sparks the whole mixture slowly started that P4 volcano cook. Where 1 side turns white hot with a ring of orange around it from escaping phosphorus. Then the ring expanded over the whole pile and cooked to death releasing lots of white smoke.

Interestingly enough what was left afterwards was a very bright, almost white/yellow powder with random pockets of dark grey.

According to wiki Z2P3 is suppose to be very dark grey almost black. But what puzzled me was all the white yellow. The slag was packed with some type of metal oxide it had to be zinc.

Anyway, when it cooled down I put water on it and saw not 1 bubble.

Based on what I just saw... the zinc is most definitely going for the oxygen and not the phosphorus.

I can't say that for sure yet but I'm definitely ordering higher grade powder and this needs to be tested.

Magpie - 18-3-2016 at 08:12

...Anyway, when it cooled down I put water on it and saw not 1 bubble.

Based on what I just saw... the zinc is most definitely going for the oxygen and not the phosphorus....

Very interesting. But on a larger scale in a closed retort access to atmospheric oxygen will be restricted. This may promote the formation of phosphide.

Please be careful.

blogfast25 - 18-3-2016 at 09:13

Very interesting. But on a larger scale in a closed retort access to atmospheric oxygen will be restricted. This may promote the formation of phosphide.

Please be careful.

Personally I think Zn₃P₂ could only be formed if an excess Zn is present.

halogen - 18-3-2016 at 09:32

Zinc oxide is known as a particularly volatile metallic oxide. Historically, zinc was discovered because it was noticed that when the sublimated deposits of zinc oxide in the flues for copper smelting were added back into the copper, the quality and color of the metal changed, producing what we now call bronze.

Aluminum also forms a phosphide. It used in semiconductor technology. Only lead and bismuth (of the relevant metals to this topic, afaik) refuse under all conditions to combine with phosphorus.

Metacelsus - 18-3-2016 at 13:48

Historically, zinc was discovered because it was noticed that when the sublimated deposits of zinc oxide in the flues for copper smelting were added back into the copper, the quality and color of the metal changed, producing what we now call bronze.

Sorry to nitpick, but I think that would be brass, not bronze.

clearly_not_atara - 18-3-2016 at 15:18

Quote:

Only lead and bismuth (of the relevant metals to this topic, afaik) refuse under all conditions to combine with phosphorus.

Silver phosphide exists, but it does not hydrolyse to release PH3 except by reaction with hydrogen, since the electronegativity of silver (1.9) is so close to phosphorus (2.2) that the compound is essentially nonpolar, but the phosphorus atom is still easily oxidized:

https://books.google.com/books?id=qKQl6Ypl4KoC&pg=PA9&am...

Quote:

2 Ag3P + 3 H2O + 5/2 O2 >> 6 Ag + 2H3PO4
2 Ag3P + 3 H2O + 3/2 O2 >> 6 Ag + 2 H3PO3

Since AgO is not a product it stands to reason that PH3 production is unfavorable (and realistically Ag+ should oxidize phosphine). Notably, silver metaphosphate (AgPO3) melts at a surprisingly low temperature, 482 C if you believe Wikipedia -- so maybe you can melt the phosphate, not the reductant!

https://en.wikipedia.org/wiki/Silver_phosphate#Other_silver_...

https://books.google.com/books?id=aDI9AAAAIAAJ&pg=PA300&...

[Edited on 18-3-2016 by clearly_not_atara]

BluePlanet1 - 19-3-2016 at 20:48

Alright, I got my camera set up yesterday & recorded a demo cook that was a bit dark. So today I built some hand held 200 watt clamp lights for good lighting. With the lights set up the video comes out in true HD which is cool. Then there's a higher HD setting I haven't tried yet so this camera is great. Very happy with it.

The bad news is apparently I left the seals on my retort too long (like 10 hours). I came back with my camera today to undo the seals. Now it seems to be permanently bonded. I boiled it in water for like 30 mins. Beat it with a hammer like last time. Tried the biggest wrench I have. I can't break, shake, losen or get these seals off no matter what.

I also noticed some weird properties that occur when conc sodium silicate and silica dust sit for too long. The adhesive I made yesterday I had left over that I left in a SEALED air tight bottle. It was a small bottle with very little air.

I looked at it and thought it was still liquid. Then turned the bottle upside down and noticed it wasn't moving. Then opened the bottle and noticed the adhesive in the bottle somehow cured. And it cured soo hard I can't even break it with a hammer and nail. It's really weird as the nail goes in a bit through the surface but it's almost like the adhesive is partially elastic and pushes back on the nail head.

So then I did some more reading and noticed that silicates are used in BULLETPROOF MATERIALS ? There are patents right online for using potassium silicate to stop bullets lol.

The only thing I can think of is the conc silicate solution sat with the silica so long that the silica pulled the water from the silicate. So basically, the silica "dried" the waterglass. And the polymer that forms afterwards is a very weird material. When there's moisture still in it although it's "rock hard" it gets a tacky, elastic type of.... it's like concrete rubber. Very hard to explain.

Anyway, I gotta pick up another retort tomorrow. And I'm gonna put this all on camera with some weird questions. Maybe there are chemists on here who can explain how a polymer like this can cure and form in an air tight bottle. It seems like more than just silica drying the water glass as water should be able to break that bond but after a certain point it does not. I may wind up just molding my own retort out of this material. Then I'll use a steel housing in the cook area for easy cleaning. And possibly some compression seal rather than threads. Either way I got videos to upload they should be up soon. :/

[Edited on 20-3-2016 by BluePlanet1]

BluePlanet1 - 21-3-2016 at 22:56

OK! I've spent a couple days doing more research.

From nuclear powerplants to the nazi death-gas concentration camps ... to reddit, to the national plumbers forum then finally to mythbusters and popular science I've learned quite a bit.

First things first, I learned a neat "plumbing technique" for removing sealed pipes.

You need a real & LONG pair of plumbers pliers. Then ice water with salt is optional. What you do first is cool down the pipe. I should mention a lot of plumbers said you don't need ice water and the salt part I added. But what you do is hold the pipe firm so it can't move. I don't have a vice so I stepped on it. Afterwards you put the long pliers on the piece you're trying to get off. Then you simply apply PRESSURE to that cold part and bang it in a circle all around.

They said as the pipes contract if you hammer with strong pressure applied (in 1 direction) the seal cracks.

I personally think just having longer plies did the job.

Here's what else I learned. As I was reading I noticed a pattern of many people on reddit, national plumbers, etc mentioned the same compound over and over.

It's called "x-pando" : http://www.vatoraccessories.com/catalog.php/vatoraccessories...
More info here: http://www.xpando.com/xpando.php
MSDS here: http://www.xpando.com/msds/X-PANDO%20PIPE%20JOINT%20COMPOUND%20SDS%20(US)%203-9-16.pdf

But here's the cool part. I found this article from Popular Science called "Mythbusters Workshop: Extreme Plumbing."

In the article Adam & Jamie talk about how they spend a lot of time in plumbing stores. And how they usually head to the NPT section. They talk about some crazy plumbing stuff they've done, explosives, high pressure, etc. And the part at the end (2nd to last paragraph) talks about a 250lb rocket they built in 3 days with NPT fittings. They said they needed a sealant that can handle high temperatures and pressure and the product was once again X-Pando: http://www.popularmechanics.com/science/a1455/4213140/

X-pando is also the site I learned the technique from.

It uses magnesium chloride, limestone, magnesium oxide, graphite and dextrin.

I've been using sodium silicate and silica.

But I'm gonna pick up this product tomorrow and compare them. The main issue I'm facing right now is I can create a strong seal. But the questions are "how strong does the seal need to be?" and "is there a way to make the seal *weaker so it still works but comes off easier?"

What I like about my "SS" seal is it's instantly curable. The problem is even a thin film around the pipe will expand in open to about 5xs is size. So inside the pipe that stuff is expanding and getting extremely dense.

I'm basically on a mission to make or find the perfect pipe dope. Fiber and ceramic paper have to be ruled out cause they tear. Then the high grade stuff is really expensive. I'm also not confident about woven glass fibers being very airtight. Maybe in a gasket compressed flat. But wrapped around a pipe I see the threads ripping right through it.

It could be possible that the talc I added... which I thought ruined the bond (it does make it less sticky)... maybe the right % of talc will soften up the cure. The way I see it, talc is the softest mineral known to man. I need a high refractory material which could be anything (silica, alumina, etc). I need a binder like waterglass or dextrin. Dextrin I'm against cause I've never fire cured it. At the same time the goal isn't to cure anything. The binders are simply to get the refractory around the threads then tightened. After that point the binder is useless. So maybe I can experiment with dextrin. The way I see it, you only need 2% or so. That gets the material in the pipe. You fire it. Ideally (somehow) control expansion. Less expansion would be better. And if there's just a bit of talc in that seal it should make it brittle enough to pop right off.

This is all just useless theory.

These next few days I'll be cooking phosphorus but very small amounts just to test and remove the seals. One way or another I'll find the right balance of whatever I need that creates an airtight seal but also comes off easily.

ps. I still have a video to upload I just gotta edit it and have been busy with this pipe dope stuff. :-)

[Edited on 22-3-2016 by BluePlanet1]

chemrox - 22-3-2016 at 16:36

Over 1200 post? Why all the interest? Could someone re-post the method for conversion of red P to the pyrophoric version? "pyrophoric" is not in the dictionary?

BluePlanet1 - 22-3-2016 at 19:24

I went shopping today and figured I'd just line up most of what I'm working with.

There's a few things missing like vermiculite, carbon, torches, blah... but this is most of my P4 lab.

This shows the long back up retort I bought as a plan B just encase. I can heat and bend the pipe myself then that would reduce it to 1 seal instead of 2.

My NaPO3, Al & MG.

This shows the new sealants I bought and am working with. Perlite, vermiculite (not shown), water glass, silica dust, Imperials furnace cement & mortar ($6.00 at Lowest) and Oakleys high temperature silicate putty. Then the plaster of paris I just bought to have.

The Imperials furnace cement says it can cure and tolerate temps as hot as firebrick (1093C). It makes gas tight seals. Best of all it cures with fire rapidly unlike the putty. And it's not suppose to expand like the "x-pando" which I couldn't find.... I figured that'll make it easier to crack off.

Close up of the sodium silicate

Just to show how the SS homemade stuff seals. This is a permanent seal I did with sodium silicate + silica dust. Mixed to a paste, applied, that seal right there is rock hard and air tight.

This is a close up of the firebrick cement. I tried to get the temperature but it looks blurry.

Either way I got 5 new supplies to work with. Vermiculite, perlite, plaster of paris, fire brick cement and silicate putty.

Some mixture of some type here will work how I need. I'm putting my money on the firebrick cement. Then once I get this sorted we move to the testing stage of reductants & measuring yields. Oh and the zinc dust is on it's way. There was only 1 seller on ebay selling it but I promise we'll get there soon.

Stay tuned as I'll be video taping how all these different seals work. ;-)

edit: I accidentally showed the wrong (spanish) side of the fire cement but you can see the temp if you zoom in.

[Edited on 23-3-2016 by BluePlanet1]

Daffodile - 22-3-2016 at 19:37

Where did you get that refractory brick cement? Just to get bricks, I had to go to 4 hardware super centers, and the final product left something to be desired (and I had to wait 40 minutes and talk to manager). After all that, they obviously had no cement like you have.

EDIT I know that the stuff isnt restricted, but its just uncommon.

[Edited on 23-3-2016 by Daffodile]

BluePlanet1 - 22-3-2016 at 19:47

Quote: Originally posted by Daffodile

Where did you get that refractory brick cement? Just to get bricks, I had to go to 4 hardware super centers, and the final product left something to be desired (and I had to wait 40 minutes and talk to manager). After all that, they obviously had no cement like you have.

EDIT I know that the stuff isnt restricted, but its just uncommon.

[Edited on 23-3-2016 by Daffodile]

Lowes! I was surprised myself and it was the hardest to find. If you go to the aisle where they keep PTFE tape / plumbers tape you should see stuff like "RectorSeal5", fluxes and solder.... at the very top of that shelf I noticed these big brown boxes. So I pulled a ladder over myself, climbed up, opened the boxes and it was like x-mas.

I didn't see any on the shelf (idky) they just had it in boxes at the top. Your Lowes will obviously be different but hopefully they have it.

BluePlanet1 - 26-3-2016 at 19:03

So I was watching an interesting documentary a few days ago. It shows old, african tribes smelting iron from scrap. They literally dug the clay from the ground, build everything by hand, charcoal by hand, iron ore by hand... then managed to melt and shape iron with one of their furnaces.

After seeing them do this 98% with their hands I thought "I'm retarded." If people can do stuff like this with no fancy tools I'm clearly overestimating what it takes to build a stupid seal.

Then I took some plaster of paris out and put the paste around a pipe, capped it on and let it sit. I was awfully surprised how well it sealed the pipe. So I fired it up.... the plaster outside the seal contracted and made hair line cracks. Inside the seal it still seemed air tight. The problem is the plaster loses water leading to contraction in it's pure form. Although I firmly believe that a mix of:

1 tablespoon plaster of paris
1/2 tablespoon silica dust
bit of water to paste it
a few drops of conc water glass

That mix should stop the contraction. As as the plaster loses water when fired the water glass expands. It would bind better. Should also create a softer seal that's easier to break. So I'll test that seal after this test.

RIGHT NOW I'm using furnace cement as it fires great. You take it out of the bottle and within 5 minutes it seals up rock hard. It doesn't contract. No cracks. It also gets hard as steel when fired cured. The bottle says you need to wait 1 hour before firing it. It also says you have to PREFIRE first. That was a huge mistake I made skipping the prefire as it will distort if you don't.

The 2nd time I let it sit 1 hour. Then threw it in the oven at 220F for 30 mins. Then I fired it and there was no distortion, expansion or cracks. Even the thin parts on the steel I tried to flicker off with my fingers and it wouldn't budge or flake. What I'm banking on here is the fact this stuff is for INTERIOR USE. I've thrown it in water after firing. It does lose its strength very fast, get flaky and break off. That should make seal removal easy.

Here is what the pipe looks like with the black furnace cement....

It's really good stuff. Here's another angle that looks like a weld:

After it air cured (1 hour) I charged the retort then sealed the 2nd seal:

Here's a closer pic. The bottom seal is a bit messier as I wasn't aware how fast it would cure. So it looks a bit rough. But that inner seal (under the surface & in the threads) went on as smooth as it gets. Adding a bit of water helps slow the cure time which I did on the 2nd seal.

This was after I took it out the oven. Literally no change in appearance. And it looks the same exact way when you hit it with hot air-propane.

There is NO WAY in hell this retort is breaching or locking up.

According to the MSDS it contains:

Silica, Quartz - 40-70%
Hydrous Aluminium Silicate - 15-40%
Sodium Silicate - 10-30%
Sodium Hydroxide - 1-5%

That's a smart formula imo. As my homemade stuff was around 60% silica with 40% conc sodium silicate solution. The issue was my stuff expanded too much and was very resistant to water. But I never thought of adding more lye. It makes sense that by doing that... when it's fired the lye reacts with a small portion of silica to form more sodium silicate.

But I still don't get why their stuff breaks down fast when exposed to water and mine doesn't.

I can only assume the aluminum silicate and (or) unreacted lye is making it more vulnerable to water. That has to be what it is. Cause molten lye will react with silica to form more sodium silicate and a stronger bond. But the reaction is very slow even when done in pure stoich ratios. So in this impure state, there HAS TO BE unreacted lye left over after firing. And that little bit of unreacted lye which is highly water soluble allows the materials to quickly break down when exposed to water. That's gotta be what's happening. I need to add a small % of lye to my own stuff and test.

Anyway, I could fire this right now but it's a bit late so I'll film it tomorrow... which is Easter ... uh, we'll have to see. Either way I know this is gonna work great and it's making me a lot more confident to begin using my larger retort. I'll fire regular Al first. Next fire I'll do Al/MG/C possibly with a different seal. Then I'll move to my larger retort if all goes as planned.

ps. I know that P4 + lye = phosphine but we're talking a very low potential amount of lye and tight seals mostly blocked by silica and silicates... I don't think it'll be an issue.

[Edited on 27-3-2016 by BluePlanet1]

Magpie - 27-3-2016 at 14:52

Nice dog you have...seems interested in your work too.

I can't help but think that your pipe assembly could be simpler and cheaper. It looks like you are going from 1.25" or 1.5" steel to 1/2" brass.

If you used a 1.5" x 1/2" street ell reducer street ells, then a 1/2" coupling, then a piece of 1/2" pipe you could stay all steel. This should be cheaper and simpler. What do you think? Is there some reason you want brass on the condenser?

BluePlanet1 - 28-3-2016 at 21:30

Nice dog you have...seems interested in your work too.

I can't help but think that your pipe assembly could be simpler and cheaper. It looks like you are going from 1.25" or 1.5" steel to 1/2" brass.

If you used a 1.5" x 1/2" street ell reducer street ells, then a 1/2" coupling, then a piece of 1/2" pipe you could stay all steel. This should be cheaper and simpler. What do you think? Is there some reason you want brass on the condenser?

Thanks. It's actually a 1" steel pipe brought down to 1/4".

The reason I used 1/4" brass is because I thought a sharp drop in size would force the P4 to liquefy better. And the problem is Lowes doesn't sell 1/4 threaded steel pipe.

However, after this last cook it's clear I have no idea what on Earth I'm doing. I'm not even gonna bother explaining since all 30 mins of this disaster is on video.

Right now I'm compressing the file down. I wanna get this on YT asap cause it shows how dangerous & unpredictable this reaction really is. It also shows everything that can possibly go wrong all in 1 take.

I'll be back very soon with a link.

[Edited on 29-3-2016 by BluePlanet1]

BluePlanet1 - 30-3-2016 at 01:15

Ok, video is done but in the wrong format at 360p. I had to read and Google forums said it's a "glitch". I also had to edit it down from 28 mins to 12 mins. If someone kind knows how to embed it I'd appreciate it.

https://www.youtube.com/watch?v=1kisHHTqi7M

That brass was hot as heck so why so much P4 got stuck in it... when it should have been liquid... I have to switch to steel.

j_sum1 - 30-3-2016 at 04:28

Congratulations on your success -- of a sort.

Some thoughts.

1. I am glad that someone has paved the way before me. It is so good to learn from watching someone else before attempting for myself. The phosphine was good to witness from a distance.
2. I think a bigger diameter is needed for your retort. Switching to steel would be good too. (See point 3) you have your P clogging up inside the pipe.
3. Your temperature control is not quite right. That I think contributed to the clogging. MP is 44C. BP is 280C so you should be in the range to get liquid in the pipe. However, because copper conducts heat so well, it may be that you get solidification before the P hits the water. Steel would help here. Using hot water would also help. I would be inclined to put an immersion heater in the water and keep it around 80C.
4. There is a problem with your setup in that you cannot let your gear cool down without drawing water up into the retort. I don't know that you want sudden cooling and possible steam formation added to a tricky setup. The ability to feed some argon or something through a hose in the water and into the retort as it cools would help a lot. I envisage a kind of a "J" shaped tube that you can simply immerse into water and into the retort and let a slow stream of argon bubble out. Then you have no hurries. You can let the whole apparatus cool at your leisure and retrieve the phosphorus later.
5. You need a better scraper than a fork. You need a better method for reclaiming the product.
6. If it was me, I would immerse the whole thing into a tub of water once it has cooled and then disassemble it under water. Then you don't get any losses. You can have already prepared an appropriate sized plunger to push the contents out of the pipe. Again, this buys you time. You don't need to rush anything. You can do a physical separation of your product and anything else that you find in the retort. You can expose it to air when you decide to and not during transfer.
7. You already know this but some better protective clothing is probably warranted here. Nice to have a gas mask. For this one, I think outside is preferred to a fume cupboard. I'd prefer some running distance.

clearly_not_atara - 30-3-2016 at 14:42

I'm a little curious as to how phosphine production might be minimized when blowing P2 (g) into H2O.

I know there are some metal salts (only Ag+ and Cu+ come to mind, but I know there are others) that will form insoluble phosphides by reaction with phosphine in solution -- condensing phosphorus into a solution of such a salt should trap any PH3 that forms as a result, maybe?

Obviously precautions related to H3P must be taken nonetheless but even with a fume hood that PH3 has got to go somewhere, and I'd prefer it be nowhere, lest it react with a piece of Al somewhere and only hydrolyze months to years later.

A slightly cheekier idea is blowing the phosphorus into 3% aqueous H2O2, but that could easily start a fire.

Magpie - 30-3-2016 at 15:53

A "wife beater" and no gloves is not adequate PPE! I cringed as I watched you poke the burning P out of the condenser. If you get some of that burning P on your skin you will rue the day you decided to experiment with it.

Keeping the condenser at the right temperature is something I struggled with also.

[Edited on 31-3-2016 by Magpie]

BluePlanet1 - 1-4-2016 at 20:25

Thank you all for the feedback. I will definitely use PPE next time I promise.

Temperature control is a serious issue so I figured it's time for a "tune up". I went back to Lowes today to buy a 10PSI bayou regulator ($22). I also bought an addition $8 propane knob, $12 350PSIG hose, brass fittings ($16) and a badass 6" steel burner pipe with a flared (reverse reducer) end. The propane was also very cheap it use to be $25 for a refill but right now Lowes is charging $15.

So now I have both a 10PSI regulated hose and an unregulated hose. Very similar to this: https://www.youtube.com/watch?v=eO8NwseRxSA except the unregulated hose is complete overkill. The 10PSI one sounds like a jet engine. The unregulated hose even when turned on super low is like a blast furnace. I've never seen anything like it cause I was standing 5 ft away from the flame (behind it) and started sweating.

Tomorrow I'm building 2 forges. 1 small forge dedicated to my smaller full steel retort. It now has a steel elbow and wider steel distiller.

Then a bigger forge for my 300gm retort which is also all steel. I know I can probably use just 1 forge but I want them both sized appropriately.

I read when air-propane is optimized right it can get up to 1995C or 3623F. Then from the tests I did today, I put a huge steel pipe in front of the flame and instead of orange it got very bright yellow to the point the vice grips closed (pancaked) the steel in half then it fell in a bucket of clay.

With this set up I'll be reaching much hotter temperatures, much more even heat distribution, the elbow will get yellow hot, the distiller will probably stay orange. My goal is to vaporize every bit of WP out of the retort straight into water.

When I look back at the video... I was underpowered BTU wise and had poor heat distribution & insulation. Then also brass... the differential expansion between steel and brass, breaching right at that point and no other tells me all steel should work much better.

I'll be working on this over the weekend and will get back to more trials early next week. I really think the forums gonna love this. :-)

BluePlanet1 - 13-4-2016 at 19:49

Hey all.

I doubt many are wondering but I'm waiting on a drill bit set in the mail. The small, #61-#80 size which are due to arrive next monday.

It's a long story but the propane burner I built was way too big as stores don't sell drill bits smaller than 1/16". And when I turn it down low it doesn't burn optimally.... the pipes just too big for such a small forge.

So instead of using the "gasblaster" design (from Grant, King Of Random on YT) I'm building this burner instead: https://www.youtube.com/watch?v=uIRTcmR6sSk . I never realized you can hack the regulator on the small tanks so they can burn like that. And you can also refill the small tanks easily with 1 bigger tank.

Right now I got all the pieces for the burner I'm just waiting to drill 1 hole. This way I'll have a more compact / efficient design and in the end it'll be plenty hot enough for 50-300+gm charges. My forge is also very cool. I put a small metal brace in to prop the retort right in the middle. When it's complete it should work beautifully. It actually looks somewhat like rogers retort just smaller and in a coffee can sized forge. I'll start posting pics & videos by the middle of next week!

-BP

OldPhart - 13-4-2016 at 23:50

I for one am glad for the update-no news for nearly 2 weeks on a project like this one could have any number of potentially negative/unhappy endings.

The smells on a burn unit are truly unforgettable and was definitely hoping you weren't occupying a bed in one-or worse...

PS-

OldPhart - 14-4-2016 at 00:00

You can now get micro drill bits at Harbor Freight! $3.99 for an assortment of 30. I have not yet tried them but the reviews seem to be more positive than negative.

http://www.harborfreight.com/high-speed-steel-micro-drill-bi...

halogen - 15-4-2016 at 08:32

Sodium metal the old way involves similar temperature and apparatus. It was distilled from a mixture of sodium carbonate and carbon. You wouldn't do it inside, the byproduct is carbon monoxide. The process for potassium metal was the same, substituting potash for soda ash.

Intimate mixture of carbon and the alkali carbonate salt is the most important factor. No finer mixture can be obtained than by charring the tartrate without air; this was impractical on larger scales so combination of pulverized charcoal were optimized. Presumably other organic salts work to some extent. Cream of tartar, a byproduct of winemaking, is used in hollandaise sauce, beating eggs and other culinary inventions.

The book Aluminum (Joseph W. Richards 1890) has a chapter on sodium, which was required for aluminum production before the Hall (electrolytic) process. Other sources can be found, for example one describes a gun barrel as the ideal retort for demonstrating the production of some potassium droplets from potassium tartrate.

Due to potassium's greater reactivity with carbon monoxide it could form a black "explosive" deposit on the sides of the condensing flue. This wasn't a problem with sodium.

JJay - 15-4-2016 at 08:34

Sodium metal the old way involves similar temperature and apparatus. It was distilled from a mixture of sodium carbonate and carbon. You wouldn't do it inside, the byproduct is carbon monoxide. The process for potassium metal was the same, substituting potash for soda ash.

Intimate mixture of carbon and the alkali carbonate salt is the most important factor. No finer mixture can be obtained than by charring the tartrate without air; this was impractical on larger scales so combination of pulverized charcoal were optimized. Presumably other organic salts work to some extent. Cream of tartar, a byproduct of winemaking, is used in hollandaise sauce, beating eggs and other culinary inventions.

The book Aluminum (Joseph W. Richards 1890) has a chapter on sodium, which was required for aluminum production before the Hall (electrolytic) process. Other sources can be found, for example one describes a gun barrel as the ideal retort for demonstrating the production of some potassium droplets from potassium tartrate.

Due to potassium's greater reactivity with carbon monoxide it could form a black "explosive" deposit on the sides of the condensing flue. This wasn't a problem with sodium.

This thread is about phosphorus.

halogen - 15-4-2016 at 08:39

It's probably not common knowledge and the present participants in the extended conversation

blogfast25 - 15-4-2016 at 08:44

It's probably not common knowledge and the present participants in the extended conversation

It's been mentioned in the sticky potassium thread (it works with potassium too).

WGTR - 15-4-2016 at 10:11

The book Aluminum (Joseph W. Richards 1890) has a chapter on sodium, which was required for aluminum production before the Hall (electrolytic) process.

Thanks for the source. That was an interesting read.

I've made small amounts of phosphorus in a borosilicate tube before, using the general hexametaphosphate/aluminum method before. The tube was under a good vacuum, and the borosilicate was barely able to handle the heating without completely caving in. Soda lime glass wouldn't have been up to the task, due to its lower softening point.

However, 1000C+ temps aren't hard to achieve with Kanthal or nichrome resistance wire. If I did this reaction again, I'd probably use a sleeved reactor design. Both the reactor and its jacket would be under vacuum, so the reactor would be protected from both air oxidation and pressure differentials. The resistance wire would be wrapped around the reactor, and the jacket would be air or water cooled. I'd probably put a window at the bottom of the jacket, so that I could monitor the reactor temperature. I'd probably use a steel alloy for the reactor.

At about 1000C, the reduction with carbon might be feasible in this type of design.

BluePlanet1 - 27-4-2016 at 19:12

Quote: Originally posted by OldPhart

You can now get micro drill bits at Harbor Freight! $3.99 for an assortment of 30. I have not yet tried them but the reviews seem to be more positive than negative.

http://www.harborfreight.com/high-speed-steel-micro-drill-bi...

Awesome find thanks for the link! I broke all my really small bits and had to settle for a #74 but I'm gonna pick up like 3 sets tomorrow.

As of now the burner & forge are basically finished. It took like a week just to dry. The orfice technically should be smaller at #78. And it's *slightly off center which leads to fluttering & backfire at low-med pressures. But when I turn it up all the way the fire stays 95% in the forge with minimal backfiring.

I've also done melt tests and it melts aluminum, copper & brass with ease.
More interestingly I swapped my propane for MAPP then stuck a big iron nail in. After a couple minutes the tip melted off so I bended it in half. Then stuck it back in and saw iron sparks blowing out. So I pulled it out, hammered it down and it fused like a legitimate forge weld. MAPP gas is expensive and only suppose to burn 100C hotter than propane... with small torches that is. But in the forge it seems to burn much hotter.

Anyway, all things are set to fire off. For now I'll have to do the larger 300gm one. Since my options for the forge are either "off" or "fullblast." That is until I size down and recenter my orfice.

Only thing holding me back now is courage. It all looks very neat, compact and sophisticated. But when I run my mind through the logic of what I'm actually doing... I'm setting off a controlled explosion within a controlled explosion.

I'm definitely not jumping into this full scale on my first run. Maybe I'll start with 50-100gms first. Or maybe I'll just try to drill a new orfice tomorrow. The worst I can see happening is the retort gets yellow-white in the forge....the reaction fires off driving it to a whiter yellow.... and I can't lower the heat (can only shut it off).. then I choose to keep it on cause I'm stupid and think the steel will hold up... meanwhile the retort melts launching molten white P4 and slag all over my lawn. Either that or the retort explodes right inside the forge blowing the burner off as it swings in circles like a flame throwing snake burning me & the whole town to ash.

F##k that. I'm doing baby steps first. Then I'll work my way up in increments of 50gms as I work on the orfice between runs. Nothing larger than 150gms till that orfice is perfectly centered.

To conclude, I just gotta grow some balls ideally by Friday. I'll set everything up, hopefully report back and have a video by Saturday. Just so the forum realizes though, this is all dependent on my mojo. If I disappear till next Monday I will come back with some lame excuses. But I DO PROMISE to get this whole process (trials 2, 3, etc) started by next week at the LATEST.

So Friday if mojo is good. Early next week if I somehow get smarter by Fri. It might be better to say I'm just waiting for a sign from the phosphorus gods.

Magpie - 28-4-2016 at 09:50

Your apparatus should as far as possible be failsafe. Give the reaction products plenty of opportunity to vent safely when the reaction takes off.

Gruson used an oxy-acetylene torch to heat his retort. Take a look upthread.

That's a lot of work

SilverMiner20ozTons - 1-5-2016 at 04:00

I remember just scrapping it off the back of matchboxes soaked in acetone? That was a joke only some members did.

Furnace Concept

careysub - 11-6-2016 at 07:40

On my way to work (I have a long commute) I like to design things in my head, and got to thinking about how a phosphorus producing furnace might be built and operated. I assume that this reaction works better at larger scale, so the focus is on how a "max scale" system within the constraints of a residential set-up might be built at a reasonable cost.

An arc furnace, like those used commercially, seems compelling to me since it easily gets the very high temperature required, and with internal heating is efficient and spares the reaction vessel from having to take the full heat.

The basic idea is this: use a graphite crucible for the reaction vessel, with a vertical rod (or rods) striking the arc at or close to the bottom (using a sacrificial graphite disk, not the crucible itself). The crucible would be in an ordinary steel drum, either 5 gallon of 10 gallon depending in the size of the crucible. The drum is used to maintain the gas seal, keeping oxygen out, and efficient containment and collection of the phosphorus vapor. Carbon dioxide flushes the can before the arc is struck, and a flow of CO2 is maintained during operation.

Some points about this:
Graphite crucibles are available to pretty large sizes at reasonable cost and are rated to 1510 C:
http://www.budgetcastingsupply.com/Crucible-Clay-Graphite-Bi...
The crucible would rest on a refractory insulating support so that the drum is not subjected to the intense heating.
The drum has an resistance heater inside of it for preheating to 300 C, and is well insulated. It may be that simply using the arc system in a "low power" mode to preheat the unit would all that would be needed.
The entire vapor capture system is insulated and heated (except where the product is collected) using heating tape, etc.
The entire apparatus - drum and collection system is preheated to 300 C before the arc is struck, so that there is no possibility of phosphorus condensation except in the collector.
Silicone gasket RTV is readily available rated to 343 C, and up to 400 C can be had. This would be used to seal the drum lid before operation.
I would put in some sort of odorant that volatilizes as this heating takes place to ensure the entire system is sealed, phosphorus vapor being quite toxic.

The crucible/arc could be set up and operated in one of two modes:
1. uninsulated crucible, with the arc designed to reach a temperature well above 1500 C inside the reaction mass, and using a localized reaction zone, with slag collecting at the bottom as the reaction proceeded.
2. insulated crucible with the objective of heating the entire crucible to 1500 C so that the entire loading would be evenly heated.*
In the first case you would use a max size crucible (like the one I linked to above), in the second a smaller crucible would probably be best.

Modern home circuits can support up to 12 KW (100 amps, 120 V) so that would be the max power for heating, and would inform the correct scaling of the crucible size used.

(Initial flushing of the system could be done conveniently be placing some dry ice in the bottom before sealing. The cold dense gas would displace and flush the air efficiently and cheaply. You have time to kill while the RTV sets.)

Any comments about this concept? Problems? Improvements?

*Insulation scheme, use a 1670 C rated castable for the crucible holder shell, with a light-weight insulating castable (rated to 1450 C) as an outer jacket. High temperature insulating wool or ceramic fiber paper fills the rest of the drum.

[Edited on 11-6-2016 by careysub]

Magpie - 11-6-2016 at 09:13

I think your basic idea is sound. As you say the challenge is to develop a safe and economical device.

Page 47 of this thread shows an arc furnace design by Landis that would work for medium scale (back-yard) production. But it would be too expensive for occasional production with no sales to support the capital and operating costs.

I'm skeptical of using RTV for a sealant. I've used it before for P production with less than satisfactory results.

I'm a proponent of compression seals. Refractory braided gaskets and rope are cheaply available at barbeque stores. Large drums (33, 55 gal) have lever-operated ring closures available for sealing drums. These may be available for smaller drums also. I don't think they are intended to be liquid tight but with proper gaskets might be made gas-tight for low pressures like you anticipate.

The Landis design uses a gland seal for the consumable rod that is pushed into the arc. I would use a braided refractory rope for that also. Aluminum plant carbon electrodes employ a screw to maintain a seal. I think the commercial P plants do the same.

It is interesting that you intend to operate this device at a slightly positive pressure rather than a slight vacuum. A slight vacuum would help with containment issues.

What would be your batch production size?

[Edited on 11-6-2016 by Magpie]

careysub - 11-6-2016 at 11:29

Thanks, that's the sort of feedback I am looking for. I'll look at other sealing strategies. I view that as the most troublesome part of this scheme.

My thought about positive vs negative pressure is that I want the seals to be tight, so they should not be leaky (the barrel lid seal is the tough part), but I want to move the product efficiently out of the system for collection. Positive pressure (from a CO2 tank) is easy to supply.

The batch size for the "max" concept is whatever mass of reactant could be accommodated with 12 KW of heating, I have not tried to estimate that yet (anyone able to through out a plausible guesstimate?). There may be metric available about arc furnaces with rules of thumb about power densities such as KW/L or KW/kg.

Graphite crucibles are available in large sizes, the one I linked to could hold 20 kg of reactant (with a packing density of 1), which I am sure is more than can be used, so that is not a limiting factor.

This is (at this point) just a conceptual design exercise.

Once I get a good handle on a "max" system, I'll think about how it scales down. For example an inexpensive Harbor Freight arc welder which I could probably get discounted for $75 is a 70 amp unit, which would be ~8 KW, scaling down the power by a third. A suitably smaller crucible would fit in a 5 gallon pail I think, etc.

Since this is intended for batch, and not continuous operation (unlike the Landis design) many aspects can be simplified - I was not intending to have any carbon rod feed other than gravity perhaps (a holder at the top could provide mass to assist feed). It would be useful to know the dimensions and power level of the Landis system as a scaling guide.

[Edited on 11-6-2016 by careysub]

careysub - 11-6-2016 at 11:43

10 gallon drum with a bolt ring enclosure looks promising. Even with a modest crucible, the greater volume of the 10 gallon might be valuable to provide insulating and working space.

"The Electric Arc Furnace" (1914):

https://ia800204.us.archive.org/19/items/electricfurnace00st...

looks like it has all the formulae and data (supplemented by actual refractory properties) to do design calculations. I'll get back to you all when I have done some.

[Edited on 11-6-2016 by careysub]

DFliyerz - 11-6-2016 at 12:05

While buying some steel pipe to build an apparatus to try this with trisodium phosphate, I found a large bag of inexpensive "triple superphosphate" (CaH4P2O8) which I want to try as well. However, I can't find any good sources as to the thermal decomposition products of this phosphate. Anyone have any ideas?

Magpie - 11-6-2016 at 12:47

@careysub: Yes, I think the 5-gallon size would be big enough. Minimizing the internal volume would facilitate start-up and shutdown.

I don't know how fast the carbon electrode would be consumed. I suspect the arc length is critical so you may need a feeding mechanism. Manual seems OK if you monitor the amps and push in more rod if amperage drops.

When you finish a run and pop the lid the whole thing may catch on fire. I don't know how effective the CO2 purge would be. Like you say, if everything is kept hot it seems the CO2 purge would work.

I wouldn't want to push a 100a service to the limit. I would shoot for something less, say 75a or so.

I assume you are going to want to reuse the carbon crucible. Is the CaSiO3 plug going to be easily removable? It seems that a good tap should allow for it to drop out. Which brings up a design problem: will not the liquid CaSiO3 form an insulating layer on the bottom of the crucible? I think P furnaces form the arc between vertical carbon electrodes.

The more I think about the positive pressure aspect the better I like it. Any sucking in of air would result in burning P. N2 and Ar would also work as purge gases but may be more expensive than CO2.

[Edited on 11-6-2016 by Magpie]

[Edited on 11-6-2016 by Magpie]

[Edited on 11-6-2016 by Magpie]

careysub - 11-6-2016 at 15:09

@careysub: Yes, I think the 5-gallon size would be big enough. Minimizing the internal volume would facilitate start-up and shutdown.

If I can find one with the hoop closure. So far the smallest I have seen it in is 10 gallon.

Quote:

I don't know how fast the carbon electrode would be consumed. I suspect the arc length is critical so you may need a feeding mechanism. Manual seems OK if you monitor the amps and push in more rod if amperage drops.

If an arc is used then yes, this needs to be studied. This is an area I have not investigated in depth yet.

But it may not be an arc (I should have mentioned this in my original post). If the whole crucible heating method is chosen resistance heating with a continuous resistance element would be used which would not be consumed (at least, not in the same manner, some erosion would probably occur I expect).

Quote:

When you finish a run and pop the lid the whole thing may catch on fire. I don't know how effective the CO2 purge would be. Like you say, if everything is kept hot it seems the CO2 purge would work.

Right. This was part of my thinking. Perhaps gently increasing air admixture to oxidize remaining product before opening the container?

Quote:

]
I wouldn't want to push a 100a service to the limit. I would shoot for something less, say 75a or so.

I'd probably go with the 70A arc welder in reality.

Quote:

I assume you are going to want to reuse the carbon crucible. Is the CaSiO3 plug going to be easily removable? It seems that a good tap should allow for it to drop out.

Don't know. Perhaps pressing a layer of loose carbon material in the bottom to create prevent bonding? But yes, drilling a tap in the bottom to drain into a slag receptacle would be a good idea.

Quote:

Which brings up a design problem: will not the liquid CaSiO3 form an insulating layer on the bottom of the crucible? I think P furnaces form the arc between vertical carbon electrodes.

That is one thing I already thought about. Solution: that sacrificial graphite disk. It sits above the bottom with a drain and it makes electrical connection with the sides of the crucible. The slag drains to the bottom. This would be used even with the resistance heating option.

Quote:

The more I think about the positive pressure aspect the better I like it. Any sucking in of air would result in burning P. N2 and Ar would also work as purge gases but may be more expensive than CO2.

Yes, the idea of filling the system with an odorant during the pre-run prep allows you to detect leaks. Given the small pressure differential tight sealing should be possible. Welding, brazing components as needed. Tight pipe fittings. The drum hoop seal could still be backed with silicone compound if necessary.

My strategy is, if it leaks, it is not ready to run.

Since you are oxidizing carbon, and putting out CO exhaust, I figure CO2 would be fine as a cover gas. Cheap, convenient.

Magpie - 11-6-2016 at 16:05

I assume you are going to want to reuse the carbon crucible. Is the CaSiO3 plug going to be easily removable? It seems that a good tap should allow for it to drop out.

I should have said good "rap." I think a drain tap might be overkill for this scale.

Making commercial P is a "submerged arc" process. The electric current is surrounded by the powder charge. Wiki explains this well here.. If you try to use the bottom of the crucible as one electrode it seems that it would get insulated by the slag. But carbon may well be the best crucible material due to its resistance to high temperature.

Seattle Pottery is also a good source of refractory materials as you may already know.

Here's a 5-gallon drum w/ring closure.

[Edited on 12-6-2016 by Magpie]

[Edited on 12-6-2016 by Magpie]

careysub - 11-6-2016 at 20:34

The concept continues to evolve.

If the "whole crucible" heating approach is taken then one wants to insulate it extremely well, and minimize the thermal mass to be heated.

The Kastolite 26 insulating refractory is rated to 2600 F (reflected in its name, or 1440 C) so if one holds the reaction temperature to 1440 C (which seems fine from the literature I consulted) then this can be used to create a "super crucible" to hold the graphite one. It needs only be thick enough to bring the surface temperature down to 1100 C where vermiculite can take over.

So: I envision a 5 gal steel pail than is entirely filled with insulation - the Kastolite crucible holder, loose vermiculite fill on the sides, hard vermiculite board underneath, and also over the loose fill, where it is sealed air tight with refractory cement.

The only empty volume in the pail is the headspace above the vermiculite board and the pail lid, which could be kept quite minimal. Escaping heat from the crucible would keep the headspace and ports above 300 C (I imagine that a good internal insulation lid over the crucible would be needed to keep the temperature down to something so modest).

The lid would have the CO2 inlet and outlet ports, which would get professionally welded with suitable attachment hardware. An excellent insulation layer is kept on top of the lid of course.

I'll have to work up a spreadsheet to calculate how large a crucible could be heated per kilowatt.

Didn't someone already try a system like this? I don't recall (from my various wander though the Great Phosphorus Thread), but it seems like someone would have.

Magpie - 11-6-2016 at 21:18

Sounds good. I don't recall any previous use of an arc furnace. This will be a very interesting experiment.

careysub - 12-6-2016 at 22:20

I did a little investigation and some simple calculations to clarify this idea, and estimate its cost.

There are two power options, use a standard 20 A 120 V circuit, and a cheap arc welder for the power (48 V) for the supply - 2.4 kW max ($75 for the welder); or use a 50 A 240 V circuit and a more powerful welder ($300-$800 to install the circuit, and $220 for the welder) - 12 kW max. I'll look at the first most closely, since it is the most plausible one to actually try.

Steel pails run $50, a bag of Kastolite $60, a bag of vermiculite $40, graphite crucibles $57-136 depending on size.

I already have four 50 A, 240 V circuit breakers in my fusebox (two for my AC, two my electric oven), so adding one should be straightforward. If I were to develop some rationale for getting such a circuit for some other reason (probably not) then the 12 kW version would be a more likely project.

I examined the resistance heating option and discarded it - getting an appropriate resistance with a continuous carbon element seems infeasible in the small system, and marginal in the large one (requires a very slender rod). So arc heating it is.

The arc rod feed actually looks pretty easy to resolve. Weld a steel feed tube to the lid, and put a PTFE seal on the top, then advance the rod by hand, minding the ammeter. You aren't going to run this thing unattended anyway.

There are always complications (I build scientific hobby stuff all the time, so I know), but this doesn't look very difficult to execute. The main trick is getting the lid made, two gas hook-ups and a feed tube. I don't weld (but know guys who do) but would have this welded professionallly (maybe two of them, one as a back-up if you can get a discount on two).

Still have to work out the scale achievable with those two power levels.

One problem though is crucible conditioning - they must be heated to a red heat empty, with the direction that it be done slowly and uniformly, without an impinging flame. In other words, in a regular kiln. Using the arc furnace itself for this probably would not work.

A single purpose heat-soak box for the crucible could be built from insulating fire brick, along the lines of other DIY furnaces presented on SM which would cost a lot less than getting a regular kiln.

Yes, I know Seattle Pottery. I have samples of different refractory insulating materials from there.

But living in the Los Angeles area I have Aardvark Clay, Laguna Clay McMaster Carr, etc. locally so I do not need to order firebricks or heavy bags of Kastolite from Seattle.

[Edited on 13-6-2016 by careysub]

Magpie - 13-6-2016 at 13:22

The Landis water seal for the carbon electrode might be a good option.

You could install a 50a breaker and wiring yourself if you feel confident of your electrical skills, thus saving a lot of labor cost. I ran a 240v 20a service to my lab for my tube furnace and space heater myself. It was no big deal.

The Landis design uses the crucible as one electrode. This is a good design for controlling the position of the central carbon rod electrode I feel. I understand that an arc must be "struck" before it will self-sustain. This design seems good for that.

I'm glad you have good suppliers locally. Shipping "dirt" is expensive. I love McMaster-Carr.

Check your local college pottery shop or commercial pottery places to see if they will fire your crucible for you.

[Edited on 13-6-2016 by Magpie]

[Edited on 13-6-2016 by Magpie]

careysub - 13-6-2016 at 17:45

The Landis water seal for the carbon electrode might be a good option.

....

The Landis design uses the crucible as one electrode. This is a good design for controlling the position of the central carbon rod electrode I feel. I understand that an arc must be "struck" before it will self-sustain. This design seems good for that.

I am pretty sure a Teflon seal, just a Teflon plug with a hole the exact size of the rod, will do fine. They did not have Teflon back in 1900. It will also allow running the seal at above 100 C (up to 280 C in fact).

Yes, using crucible as one electrode is exactly what I envisioned (though actually using an internal bridging disk, not the crucible body itself).

Magpie - 13-6-2016 at 18:09

The Landis design does not show any kind of disk for the crucible electrode. I'm not sure one is needed. I wonder what the path of the current is from the rod tip to the crucible. Maybe once slag forms on the bottom of the crucible the current goes to the sidewall?

[Edited on 14-6-2016 by Magpie]

[Edited on 14-6-2016 by Magpie]

careysub - 14-6-2016 at 07:35

The Landis design does not show any kind of disk for the crucible electrode. I'm not sure one is needed. I wonder what the path of the current is from the rod tip to the crucible. Maybe once slag forms on the bottom of the crucible the current goes to the sidewall?

Accompanying the Landis illustration is the following text:
"It consists of an iron box lined with vitrified bricks and having an inner lining of carbon blocks which form one electrode; the other electrode, E, being vertical... The carbon lining is composed of two layers of blocks, so that the inner set of blocks can be replaced, when worn away, without disturbing the outer layer. The inner tapping hole for the molten slag is plugged with a piece of wood, without any luting; an outer plug, which is luted, prevents access of air to the inner wooden plug."

His design has a sacrificial replaceable surface and a slag drainage system.

The disk in my design serves both purposes - the slag collects below the disk, the disk is the sacrificial electrode surface so that nice carefully conditioned crucible does not get eaten up by the arc. Burning a hole in your crucible is bad practice.

Magpie - 16-6-2016 at 08:59

Here's a good thread to review ("Carbon Arc Furnace"):

http://www.sciencemadness.org/talk/viewthread.php?tid=2680

My friend (a ChE) bought a used Lincoln AC-225 "tombstone" arc welder for $100. He used it to make rubies and other gemstones. He had to hire an electrician to put in the electrical service, however, so that probably cost a few $100 or so.

careysub - 16-6-2016 at 12:51

Thanks, I have now read that entire thread (and skimmed most of the available references included). I like a remark you made way back when (more than a decade ago):
"This is a very interesting problem. The more articles I read the less clear it is to me exactly how to proceed. But I'm going to keep reading."

That is pretty much how I feel.

Investigating the power supply issues has raised a lot of questions.

I note that the arc welding units I have been looking at have duty cycles of only 20% over 10 minutes. Two minutes of operation every 10 minutes is not going to cut it for an arc furnace.

This seems to be a straight-up thermal issue. The arc welder has a small air cooling fan as the only cooling mechanism (some have none).

Perhaps I could Rube Goldberg the arc welder - disassemble for the parts and immerse the transformer in an oil bath, with oil circulation and water cooling.

Alternatively there is the old, old (old!) salt water rheostat approach - which I have some experience with. A friend and I build an arc furnace in 7th grade using this, a flower pot, and electrodes from a battery (the water boiled in operation).

I thought this maybe a little too redneck for a high duty cycle furnace, but looking up liquid rheostats I see this is a very credible technology and might be a good approach with appropriate implementation choices. A key issue I have with this is not knowing how to actually design one properly, I like to be able to do at least rough performance calculations on anything I build. How much of the power is dissipated in the water bath? More research required.

And then there are the microwave oven transformer option, which combines the transformers, after rewiring into step-down versions, from several ovens. Old ovens may be cheap but this is a heck of a lot of work, and I am less than thrilled with doing a lot transformer rewiring (electrics are not exactly my thing). Also, according to the sites I visited about this, not really that cheap since rectifiers and such must be purchased.

wg48 - 16-6-2016 at 15:21

I have tried using a cheap welder and mains power via a ballast.

Cheap welders can be used continually but on lower current setting. The main problem I found was the open circuit voltage is only a round 41 volts ac so only a short arc is supported half an inch at max and easily extinguished when cold material fall into the arcs. That also means the electrodes need to be advanced frequently. I was using welding electrodes carbon ones may be better but a suspect not.

The mains ballasted version having an oc voltage of 240V was much more forgiving able to sustain several inches of arc or more in conduction mode. I used the electric cook as the ballast (oven grill and hot plates all on) perfect for quick experiments. Potentially very dangerous unless you know what your doing and your very careful.

You do not need to rectify the ac but if you do and use an inductive ballast it would be dc and support a longer arc.

The resistance of a water rheostat is adjusted by the concentration of the electrolyte. The required resistance is determined by your required maximum current under short circuit conditions. But its going to boil eventually unless the container is very large or a cooling arrangement is constructed.

careysub - 16-6-2016 at 18:20

I am continuing this discussion on another thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=12862&...
(this one seemed most applicable), since the discussion has moved on to discussions of arc furnace design not really specific to phosphorus.

BluePlanet1 - 7-2-2017 at 00:51

Hey all!

It's been 13 months since I posted (can't believe on the same page) but I think I've found my way to a great P4 distiller.

After my last video I thought I was close to figuring this P4 thing out. But after running many tests off camera, after months and months of research I started noticing some very basic, reoccurring themes & problems.

Not just problems I was facing but problems that were faced in commercial industry in the 60s, 70s and 80s. Many problems that were solved in the narrow scope of commercial industry... but are still very common.

Let me list the 2 biggest / most common issues:

1) Expansion. Also known as "intumescence" which leads to spalling.

For those who don't know what spalling is, it's when material expands and breaks away from the surface of refractory material. This was happening in every forge I made. And fire brick factories faced the same problem decades back.

Fire bricks use to be made with water. Usually some wet hydroxide like lime or magnesia lime. Which was mixed with alumina & silica then fired.

The bricks came out ok... until refractory liners began cracking & exploding.

So they switched the recipe to dry alumina and fumed silica. Which are "fused" together dry under 2 million PSI. Then fired dry to create a new type of non-porous ceramic fire brick that has no internal stress or water. This type of fire brick is what factories use today (under the liner). It can handle extreme stress. Does not crack and takes forever to age.

2) Water which creates internal stress. This was consistently my 2nd biggest problem. Refractory compounds are loaded with hydrates. And all hydrates behave differently.

Certain hydrates like sodium silicate expand 5-10xs their size when heated.

Other hydrates like plaster shrink to 40-50% their size. And worse, plaster is a flame retardant.... not an insulator! It has no role in a forge.

Many hydroxides also lose water. Like magnesium hydroxide. First it loses water from it's hydrate. Then drops it's hydroxl group at 380C to turn to into magnesium oxide which is used to line forges like aluminum oxide is.

Then you have silicates.

And this was the hardest lesson for me to learn so I'll write it in all caps...

SODIUM SILICATE WILL DESTROY YOUR FORGE.

I understand lots of people use it. I still use it. But there's a reason why so many sodium silicate compounds have been recalled from the market.

It's highly unstable. It ages fast. At the same time it heats & expands creating high internal stress... it also becomes soft like talc and crumbles to pieces.

Not that you shouldn't use any waterglass, but if you do you need to know what you're doing.

Which gets me to my next major finding. Something magpie vaguely mentioned a year ago...

CLAY IS YOUR BEST FRIEND.

If you're gonna build a forge or system to make P4... learn about clay.

Clay is unbelievably cheap AND stable. It's strong. It's easy to mold and work with. Firebrick is made of clay. And it can be mixed with SO MANY different materials to make anything you can think of.

I'll give 2 examples:

1) If you fire pure wet clay it will shrink and crack a bit. But post fire it's still very strong & stable. And if you paint a *dilute solution& of water glass to the OUTSIDE of clay, it works its way deep into the pores. Then if you fire it again you get a material that has the hard, durable strength of clay with the softer, reflective and highly insulative properties of sodium silicate.

The outside can spall and crack if you use too much sodium silicate. But it can't spall and crack the core since the core is clay and clay is stable.

2) Clay can be mixed with perlite. So you can make lighter, more insulative fire bricks.

For people who don't realize, commercial furnaces do the same thing. They use high clay fire brick for the foundation. So the foundations are hard like steel. Then soft clay liners for the insulation.

It's really a balancing act between a hard foundation that holds too much heat (like metal) vs a soft liner that reflects heat.

You don't want either or for white phosphorus, you want BOTH.

Mold your foundation with high clay composition. So you can shape your furnace into anything you need. You can build in a feedstock if you want.

Then line it with a sodium, magnesium or calcium silicate. All 3 are easy to make. A 50/50 mix of sodium silicate with magnesium silicate (talc) or magnesium oxide (cooked out from milk of magnesia) will use the sodium to bind (water soluble) and the magnesium as a stabilizing agent to slow down aging, expansion and spalling.

This post is long and more about refractory materials than white phosphorus.

But as you'll learn refractory is much more complicated than a straight forward reduction reaction.

And once you learn this stuff you can build ANYTHING YOU WANT.

The sky truly is the limit.

Right now I'm working on a sexy clay "furnace" that looks more like a mini-white phosphorus factory.

I can add forced air if I need. Can add a feedstock to push in more crude phosphate. I can power it with oxyhydrogen from my water torch to do carbon / phosphate. Or fuel it with waste oil for higher temperatures.

But again, the biggest thing that's helped is learning to work with CLAY.

Clay turns to ceramic around 1600C. And I know I'm reaching that temp with regular air + propane since I can see the clay fuse into ceramic as it cures (the outside melts smooth). It makes a super hard ceramic that you can quickfire with no spalling.

One last thing. I promised over a year ago to get more videos up and I will. I've been busy testing different compositions of firebricks and will show exactly what I used, how easy it is to make everything, then I'll start experimenting on video with different fuels. I really think oil will work with carbon-phosphate reductions since oil gets hot enough in air in to melt steel.

I'll keep the forum updated!

Chemetix - 7-2-2017 at 13:24

Great post! Refractory is critical to so many processes, your rediscovery is certainly going to help me design some high temp work.

TheNerdyFarmer - 7-2-2017 at 14:48

What sort of clay do you use?

Edit: Also what is your youtube channel? I'd like to check it out.

[Edited on 7-2-2017 by TheNerdyFarmer]

Red phosphorus from dilute nitric acid and copper (I) phosphide

dactyl - 9-2-2017 at 09:10

According to this journal, it might be possible to make red phosphorus from the addition of copper phosphide to dilute nitric acid; details are not given into this as the study's objective is somewhat different. Nevertheless, a precipitate of red phosphorus seemed to appear upon mere addition of the copper phosphide

Attachment: ja01450a002.pdf (472kB)
This file has been downloaded 564 times

BluePlanet1 - 11-2-2017 at 20:27

Quote: Originally posted by Chemetix

Great post! Refractory is critical to so many processes, your rediscovery is certainly going to help me design some high temp work.

Awesome, thanks!

Quote: Originally posted by TheNerdyFarmer

What sort of clay do you use?

Edit: Also what is your youtube channel? I'd like to check it out.

[Edited on 7-2-2017 by TheNerdyFarmer]

The clay I bought was a cheap, ShopRite brand kitty litter. It cost $4 for 25lbs worth. And I couldn't find an MSDS or ingredients (I checked everywhere online) but I'm pretty sure it's normal bentonite clay. It's gray colored & looks and acts just like bentonite.

All I do is pour a bunch in my blender and it shatters to a fine dust immediately. You can also add hot water directly to the coarse pellets, stir it real well then mold and cook. And the coarse version will cook real hard like a brick.

The downsides with the coarse version are:

1) You really need to stir, pound and mold with a lot of muscle. At least 5-10 mins for small test batches and 30+ mins for larger batches.

2) The bricks come out coarser with more micro-cracks.

You'll save a lot of time blending first since it clays up instantly and can be molded and fired within minutes. The bricks come out smoother and even when I quickfire I barely see any cracks. If you fire it slow and mix with magnesium oxide it makes great crucibles.

AFA my youtube channel I'll get a link up soon. Right now I'm just cooking and storing as many chems as possible to test on video:

1) calcium hydroxide (calcium chloride + lye)
2) calcium oxide (cooked hydroxide)
3) magnesium carbonate (washing soda + epsom salts)
4) magnesium hydroxide (milk of magnesia)
5) magnesium oxide (cooked hydroxide or carbonate)
6) anhydrous silica 99% pure ("crystal kitty litter", the clear pellets)
7) aluminum silicate clay (clay kitty litter)
8) sodium silicate (lye + silica)
9) calcium silicate (lime + silica, doesn't react properly)
10) magnesium silicate (Mg(OH)2 won't react with silica at all, no idea why)
11) perlite

On camera I'll remake certain blends I've been testing cause I BELIEVED that calcium silicate would be far superior to sodium silicate and that magnesium silicate would be far superior to calcium silicate as a binder.

The problem is Ca(OH)2 & Mg(OH)2 are so insoluble in water that they don't react with silica. If you mix them dry with medium heat (1100c) they still don't react.

Then at 2500C I thought I'd get porcelain and again, nothing happens. It just melts together then pops and breaks right back to a dust.

Normal portland cement is suppose to be made with lime + sand... but if you mix pure hydrated lime with 99% pure silica... the stuff just sits... it will appear to "bind"... until the next day when it dries it loses all its strength.

Then sodium silicate like I said before, it binds really well with silica or perlite at room temp and gets hard like a rock. But the second you bring fire into the equation it expands, cracks, and loses it's properties as a "binder".

Bentonite clay is suppose to be mostly aluminum silicates (phyllosilicates).

And the clay acts like you'd expect magnesium silicates to act. They're not highly soluble in water like sodium silicate. But they bind well with water somewhat like sodium silicate. And it has a couple unique advantages. Rather than expanding 10xs it size like waterglass... it shrinks about 10%.

So it's minimal shrinkage & very stable. Especially when mixed with 10-25% perlite you barely notice any shrinkage at all. And the main advantage it actually withstands high heat without spalling and cracking to garbage. Then the more you fire it the harder and more ceramic-like it gets.

In the longrun all my furnaces will be built with clay. But I still wanna document and debunk a lot of bad advice I see on YT.

So I'll do like 5 videos just on refractory. Maybe 10 short videos on white phosphorus like a small series. A couple click baity videos with armstrongs mixture (chlorate + WP) and a mini WP bomb. Then maybe I'll dedicate a YT channel to high temperature chemistry.

That's something I've always wanted to do is make a really cool but unique chem channel. Chemistry is inherently so boring for most people but I love it, I have some experience with marketing & audio editing I just need to learn to write and edit the best videos possible.

ps. To any mods reading this I know I'm driving you nuts I do apologize. Future posts I'll keep as videos on WP, refractory for WP... & anything off topic I'll post on reddit or other relevant SM threads if they exist.

[Edited on 12-2-2017 by BluePlanet1]

TheNerdyFarmer - 12-2-2017 at 08:44

You should definitely start a channel on high temp chemistry. There are very few videos on that.

BluePlanet1 - 16-2-2017 at 22:12

Quote: Originally posted by TheNerdyFarmer

You should definitely start a channel on high temp chemistry. There are very few videos on that.

Thanks I definitely will.

I just got done testing 5 baby forges & made a huge discovery.

That saying "one small step for man, one giant step for mankind"... that's how I feel about this right now.

Anyone who read my first post (this year) about commercial firebricks will understand the value of this. I talked about how fumed silica is used to make the best firebrick in the world.

Well I just discovered a way to make something that's NOT technically "fumed silica", but it is:

A) super easy for anyone to make
B) looks identical to fumed silica
C) behaves just like fumed silica (moves with static electricity)
D) produces a firebrick & end product that mimics both the strength & durability of commercial grade firebrick

I'm not saying it can withstand 2 million PSI like industrial firebrick. I'm not saying I'd use this stuff in a commercial blast furnace.

But to make a better firebrick you would need either A) bag of real, fumed silica or B) hydraulic press or C) both.

For now on I'm calling it "faux fumed silica". And I'll post pics if anyone wants to see but the video will show how incredible this stuff is. It's so light if you rub a balloon on your head then put it by the sides of the bucket it follows the balloon up the sides. And the bricks are smooth as cement peanut butter. They get tiny needle size pores after cooking but you won't see a hairline crack anywhere.

Will update soon!

macckone - 17-2-2017 at 17:30

Silica isn't really fire brick. You want aluminum oxide. Good refractories are 90+% alumina. The lower percentage is usually mullite bonded with the remainder being silica. Phosphate bonded can be 99% alumina and exceed 3000F.

[Edited on 18-2-2017 by macckone]

BluePlanet1 - 18-2-2017 at 18:21

Quote: Originally posted by macckone

Silica isn't really fire brick. You want aluminum oxide. Good refractories are 90+% alumina. The lower percentage is usually mullite bonded with the remainder being silica. Phosphate bonded can be 99% alumina and exceed 3000F.

[Edited on 18-2-2017 by macckone]

I hear you. Many people forget that silicone melts lower than iron and pure silica will melt in a propane forge.

But people also forget that silica combines with alumina to make alumina silicate which is the clay I'm using. And magnesium oxide melts 800C higher than alumina.

Also, the recipe I'm using with silica was inspired by an old firebrick factory. If you watch between 27:00 - 27:55 How It's Made - Fire Brick that's why I'm using silica. Anyone interested in making WP should watch that whole video. When you heat silicone oxides with aluminum silicate clay it does raise the melting point of silica through a complex chain of ceramic like reactions that I can't fully explain.

--------------

While we're on this topic of (pure) silica's low melting point.... I tried another test last night that's pretty darn interesting.

While tweaking the vent cap on my forge I noticed it's reaching forge weld temps. Then I went back reading the thermal redux with coal. Specifically the part that says "arc furnace OR gas furnace."

And I thought "why haven't I tried this yet?"

So I mixed up coal with silica and sodium metaphosphate.

I put that mix in a small crucible. I held it at the top of the forge (for better observation of the surface) and noticed that the coal redux DOES WORK in a propane forge.

The whole mixture goes molten then shrinks like 80% it's size. After I saw some Na silicate with beeds of pure silicone metal. The P4 I let burn off.

Using coal WOULD allow you to add a feedstock. Since the mixture shrinks to almost nothing compared to AL which expands like a mess.

If people go back to page 8 of this thread someone used oxy-acetylene with the Al redux and said it took "3 hours" to finish the reaction. But he also added COAL which I think set a horrible precedent for anyone considering the coal redux.

A coal redux WILL NOT take that long. Nor do you need oxygen. A simple air-propane forge reduces the mix in minutes. Plus the reaction is safer & cleaner.

No need to worry about slag clogging your vent. No worrying about explosions. No worrying about P4 burning in the distiller due to the large amount of CO2 produced. And another huge benefit is no phosphine due to no metallic phosphides.

I just want to make & store 1 more chem (phosphoric acid) cause I also wanna test that with coal down the road. After that I'll get the camera out and start filming this new forge in action.

[Edited on 19-2-2017 by BluePlanet1]

BluePlanet1 - 20-2-2017 at 23:12

I could really use some help from the forum.

For over a year I've been working to simplify this experiment. With a simple, cheap but highly effective design. Something that regular people can look at & think "yeh, I get that." So they can go out and easily copy the method with little $ or resources.

And right now I'm at that point.

Today I successfully distilled 2.8gms of very pure WP using the coal redux in a baby air-propane forge that took 20 mins to build.

I put the cold steel retort in the cold forge, this is heavy steel pipe compared to the thin retorts that magpie and roger used. But within 2-3 mins the whole retort and forge reached a blinding white heat. And seconds later the WP started coming over. Then just as quickly the distiller end failed while leaking like a sieve.

Aside from the retort this set up is so beautiful because...

1) All materials & components are cheap & easy to buy locally. The hardest material to get is the NaPO3 itself. That's the ONLY thing I really had to buy online. But you can buy other phosphates at Lowes & use displacement reactions for different salts. The most expensive thing I had to buy was the $50 TS8000 burner head from Lowes.

2) The overall size of the forge. The walls are less than 2" thick. So the furnace is smaller and more compact than any furnace I've seen in this thread. Even with a 2" pipe (large batches like rogers) you could easily do that in a small forge 5-6" wide.

3) The fuel is cheap. I have this down where there's just 1/2" of space around the whole retort inside the forge. I screw off the burner on the TS8000. So the air-propane comes out so fast with so much force it "explode burns" around the retort. It hits that thin space so fast & burns so efficiently that 95% of the flame disappears in 1-2 mins. The exhaust flames goes from blue to yellow then drops down so low (where the gas is injected) that you see no flame anywhere in the forge. The whole thing just glows white and howls... but you see no flame which is weird.

4) Because of #3 you can probably cook 1000-2000gms of reagant on 1, $3 tank of propane.

5) You don't need the explosive Al mixture. P4 from coal comes out much whiter, the whole reaction is much smoother and safer to do.

BUT THE BIGGEST PROBLEM IS THE >>>RETORT<<<.

I would suggest than ANYONE thinking of doing this reaction... don't think about the chemistry, don't think about the heat or forge or burner or any of that stuff. I'll list a million reasons on video why to copy my exact set up.

But I can't give you many reasons to copy my retort or magpies or roger or any other design I've seen in this thread.

Even now that I can weld much better and make these smooth & beautiful welds they don't work cause flux core is garbage. I should've bought a TIG welder but even if I did that wouldn't make it easier for YOU to copy.

If someone wants to add a HUGE contribution... please figure out a way to make a retort that's refillable, that can be reused, cleaned out quickly and can also handle 1600C.... preferably with easy to get common materials from name brand stores... and also using technology that's easy to scale big or small.... that also never leaks.

Because right now I drew up a new schematic for a "compression retort" but not many people are gonna like it.

The design consists of 2 pipes.

A) steel retort pipe (1 1/2")
B) 1/2" steel distiller pipe with 90 degree bend.

To connect the distiller to the retort you need a steel plate (foundation for ramming) with a 1/2" hole drilled through it. The width of the hole has to be the same width of your distiller.

Then you need a solid metal ramming pipe. This solid pipe also needs a 1/2" hole drilled right in the center.

The way this theoretically works is you put your distiller through the 1/2" hole in the steel base. So your distiller pipe faces up and goes into the middle of your larger retort pipe. Then you mix up bentonite clay with sand (clay for compression, hard sand for "bite"). And you ram the dry clay around the distiller similar to how you'd make a rocket nozzle. You slam it 8-10 times with hammer and theoretically the clay will compress hard like a rock, it'll hold the distiller, it should tolerate extreme heat and since the reaction happens at the base the escaping CO2 and P4 should not react with the clay.

Then the base will either be capped or rammed. 9/10 of my leaks seem to happen at the distiller since the distiller hangs out of the forge at a cooler temp then the retort. And also because there's no powder towards the top to act as a 2nd barrier against the P4 gas.

Ramming clay at the top should permanently stop leaks. The downside is I can't pack the mixture towards the bottom like I normally do. Which might just reverse the leak. But if I need I might pack everything like a solid rocket. Ram the distiller in. Pack the reagant in towards the top. Then ram a clay base in.

And maybe just drill out the base after every reaction I'll have to see.

My main point would be if anyone plans on copying me you should go become an expert on compression fitting steel. Compression gaskets normally use rubber. But it may be possible to somehow use gaskets with screws... where you remove the rubber gasket and pack it with dry clay... then when you tighten the bolt that squeezes 2 pieces of steel together which sandwich the clay creating a high temp seal.

I have no idea but we'll see if the clay by itself works....

[Edited on 21-2-2017 by BluePlanet1]

WGTR - 21-2-2017 at 11:51

If I'm understanding your question correctly, why not use a rubber compression fitting? Weld(or braze) steel plates to the retort and distiller ends, and bolt them together with an o-ring in between them? Use an o-ring, perhaps, that is a couple of inches larger in diameter than the tube(s) (to keep the rubber away from the hot gasses), and water cool the joint, either with spray, or a water jacket, or submersion, etc. I'm assuming the whole length of the tube doesn't need to be white-hot. If you're using mild steel, this material has a much lower thermal conductivity than, say, copper, so it's possible to have a temperature gradient from one end to the other. Stainless steel would be even better in this regard.

How is the retort holding up to air oxidation? At the temperatures you're using, I imagine that the combustion is possibly occurring catalytically on the surface of the steel.

As an aside, steel is going to melt below 1600°C; I don't think it's getting that hot. If it's white-hot, it's going to be too bright to look at, and it's going to light up the area like a quartz halogen lamp. Do you mean maybe bright yellow, maybe around 1000°C? If you have a means of measuring it, that would be useful information.

[Edited on 2-21-2017 by WGTR]

Magpie - 21-2-2017 at 14:21

I like the fresh approach of getting away from the explosive Al/NaPO3 reaction. Now you will be using chemistry closer to that of industry. As you say this allows you to just concentrate on the engineering problems associated with high temperature. I presume the furnace interior will operate at 1000°-1200°C, ie, white heat or very near it.

What are your design criteria? I will propose some for a start. Please modify to what you have in mind:

1. Re-useable equipment. Retort/condenser good for at least 20 batches.
2. Affordable. say <$200, including the furnace.
3. Batch yield of at least 15g P.
4. P vapor leakage rate acceptable for outdoor or fume hood use, say <1g.

BluePlanet1 - 22-2-2017 at 21:42

Quote: Originally posted by WGTR

If I'm understanding your question correctly, why not use a rubber compression fitting? Weld(or braze) steel plates to the retort and distiller ends, and bolt them together with an o-ring in between them? Use an o-ring, perhaps, that is a couple of inches larger in diameter than the tube(s) (to keep the rubber away from the hot gasses), and water cool the joint, either with spray, or a water jacket, or submersion, etc. I'm assuming the whole length of the tube doesn't need to be white-hot. If you're using mild steel, this material has a much lower thermal conductivity than, say, copper, so it's possible to have a temperature gradient from one end to the other. Stainless steel would be even better in this regard.

That's a great idea. I have a HUGE blindspot in the respect I'm not measuring the temp where the distiller starts. And I was just at Lowes but their infrared guns only go up to 317C. The boiling point of WP is said to be 280C.

That's really not hot at all and some heat proof rubber seal should be able to handle that heat. Only issue is the infrared gun gives me a very tight range of 37C. But I like this idea a lot. If I simply manipulated & monitored temperature better I could get away with things I never thought were possible.

Quote: Originally posted by WGTR

How is the retort holding up to air oxidation? At the temperatures you're using, I imagine that the combustion is possibly occurring catalytically on the surface of the steel.

Yep, I think that's it. A film forms around the whole retort after every time I run it then chips off like a thin layer of oxide paper.

It's hard to see but my smaller retort is coated with a black layer of oxide that chips off if I peel it:

Quote: Originally posted by WGTR

As an aside, steel is going to melt below 1600°C; I don't think it's getting that hot. If it's white-hot, it's going to be too bright to look at, and it's going to light up the area like a quartz halogen lamp. Do you mean maybe bright yellow, maybe around 1000°C? If you have a means of measuring it, that would be useful information.

[Edited on 2-21-2017 by WGTR]

I've been wondering that myself. The reason I said 1600C is when I put the crucible in with the silica/coal/NaPO3 mix I clearly saw the whole mixture turn to a molten state. I was shaking the crucible and saw bubbles (CO2) as the coal bubbled up & down and within a few minutes the whole mixture shrunk down like 80% its size.

When I saw that I thought "damn, that's melting the silica". Which should be hot.

But reading more I may have just witnessed the intermediate reaction where the NaO bonds with the SiO2.... I should know this off my head but it's something like NaO.SiO2.PO4 that's created as the intermediate and then the coal pulls off the oxygen and when it finished I just saw a little bit of silicate, small, metallic silicone beeds & some green impurities.

It's definitely getting hotter than 1100C because copper melts almost immediately and I also forge welded 2 steel rods (mild steel?) so thats where my estimate of 1500-1600C came from.

As far as the color I'd say it's around 2/3 - 3/4 white with 1/3 - 1/4 yellow. So it does have a yellow tinge. The steel doesn't get true blinding white like my oxyhydro torch but I do see flash spots (in my eyes) if I look at the bottom then look away. With HHO if I look too long I get flash spots for a good 5-10 minutes. That was before I got my goggles. With the forge I see them maybe 10-20 seconds then it goes away.