V2O5 catalyst for H2SO4 production.

GOOGLE IT, STUPID!

Too.... many.... ideas.... brain.... overload.......

I think I'll go the toilet roll route, or the aluminum can route (but doesn't the inside of those have a very thin layer of plastic?).

As for the ozone idea: Yes, I've considered it. My implementation would be a huge chamber of aluminum with a glass jar containing water at the bottom. The chamber woukld be filled with SO2, after which I'd inject ozone slowly. Since I do have a high voltage transformer, building an ozone generator should be simple enough.

But to answer your question Tacho, if the V2O5 catalyst fails, I'll prepare a Pt-on-SiO2 catalyst. The platinum wire I ordered 2 months ago (!) has STILL not arrived though, tomorrow I'll call the selling company and tell them that unless I get my wire NOW, I'll come over and kill them all.

I do like the ozone idea though. It doesn't require pre-heating the SO2 to 450C before passing it through the catalyst. That part has me quite worried.... SO3 at 450C is not something I want leaking out, aiming for my face .

Any good links to drawings of an O3 generator, Tacho? Hmm, don't those require DC, btw? Then I'll have a hard time finding a full bridge rectifier capable of handling 9kV at 540W....

The absolutely BEST solution would be to have an O3 generator able to generate O3 at a larger rate than the generation of SO2. Then it would be a trivial excercise to pump SO2 through an O3 saturated chamber. No huge, nasty temperatures.

As for my progress right now, I've just soft-annealed some copper pipe I'm going to use. Tonight I'm going to finish the combustion product filter and start casting the endplugs for the candle burner sleeve. All the Al piping is cut to size (did that a couple of hours ago).

Edit: Found this: <i>Also, if you hook a METAL (yes, some freak invented a plastic version too)
"Slinky" stretched out, to one side of an NST and suspend a wire down the
middle you'll get a ton of Ozone and corona.</i>

Very interesting. Might be worth some experimentation.

Edit2: Actually, coming to think of it, shouldn't ozone have ozidising properties so powerful that it would make SO out of sulfur without the need for combustion? Hmmm. I'll have to build an ozone generator soon.



[Edited on 2004-3-25 by axehandle]

[Edited on 2004-3-25 by axehandle]

Well, historically the NO in the lead chamber process came from adding sodium nitrate to the sulfur, 1 part to 7 parts sulfur. But I'm not going to build a lead chamber, I want to go 100% contact method.

Here's my 1st attempt at a sulfur candle. I used the thickest available whick. It's not looking good. The whick burnt to disinegration before the sulfur had melted enough to permeate the whick:


My next "candle" will use a rockwool "staff" the size of the candle, loosely packed, as the whick, surrounded by an aluminum mesh to avoid having the rockwool bending down on itself as the candle is consumed. That will also increase the burn rate as the area burning will be the cross section of the candle.

Edit: Btw, what's crazy about using ozone?

Edit2: Oh crap. It's 04:14 PM now. Time to hit the bed.

[Edited on 2004-3-26 by axehandle]

[Edited on 2004-3-26 by axehandle]

Burner design revisited. Again.

How about this? No candle at all, just a massive cylinder of rockwool impregnated with molten sulfur. Only problem remaining is a better ignition system. A ceramic staff with an embedded heating coil, capable of being heated until it's glowing, perhaps?


Edit: BTW, I've ordered about 200 meters of 0.5mm Kanthal D NiCr wire for the exhaust heater. It will arrive on Monday. I'm getting somewhere!


[Edited on 2004-3-26 by axehandle]

Gak! You couldn't make sulfur react with zinc??? If they are both in powdered form, the mixture can be used as a rocket fuel. It was quite popular in the 1950:s.

I doubt NiCr wire would stand up to prolonged contact with the molten, burning sulfur. But that's only a problem if I intend to re-use the coil.... One could use a new small coil every time, coming to think of it. But then there's the problem of how to connect it....

I have a new solution. Before connecting the outlet to the heater, one simply heats a small piece of iron with a propane torch until it glows white, then one grabs it with thongs and drops it down the outlet pipe. That should ignite the little bugger.

Edit: Missed the lead and Al part. Well, I don't want to spend a fortune on couplers when I already have a ton of Al and copper pipe, as well as a metal melting furnace. Casting Al is a non-problem, my furnace can melt brass.

Edit2: And Al is one of the few materials resistant to sulfur at all temperatures (below the Al:s MP ofcourse....)


[Edited on 2004-3-26 by axehandle]

[Edited on 2004-3-26 by axehandle]

Yup. Having the ability to melt aluminum changes one's view of life quite a bit.

The furnace itself really deserves a section of its own on my home page, but its construction is rather complex (albeit not expensive), and I'm lazy right now. One of its highlight are that it can be run for hours on a wooden table, after which its outside is only lukewarm, while the interior is glowing yellow. I apparently came up with the right refractory mix. I don't quite remember the proportions, but it contains perlite, bentonite clay type W, portland cement and mason's sand. The burner I use IS documented on my home page. The most expensive item in the construction was the 10kg composite (transparent!) propane tank.

If enough people bug me, I might be persuaded to document the little heat-monster...

EDIT: CURRENT VOTE: 1

Edit: I've been thinking of getting 2 more gas tanks: One O2 and the other ethylene(s) so I can melt iron. Don't know the right material for the crucible though....


[Edited on 2004-3-26 by axehandle]

[Edited on 2004-3-26 by axehandle]

Document, Document, Document!!!

To the unbelievers.

Heretics. Here:





Explanation: My webcam is an Axis camera server, hence my need for a long network cable.


[Edited on 2004-3-26 by axehandle]

He is melting aluminum in the middle of the night!

axe, turn everything off, put the furnace in a safe place and go to bed. Good boy!

**********APOLOGIES**************

Sorry everybody about the zinc-sulfur mistake, this is the thread:

http://www.sciencemadness.org/talk/viewthread.php?tid=1245

It was about CALCIUM sulfide and I used a lot of calcium carbonate and very LITTLE zinc.

Don't play with mercury kids, or you will end up like Tacho.

sulfur burning

IKEA

sulfur burner using an aspirator

Axehandle I hope your hangover is over. Even Norse gods must take a rest. Here are some more musings on your most interesting project:

I have another thought for a sulfur burner. Since I've read that one industrial method for burning sulfur to SO2 is to atomize molten sulfur and mix it with air, why not use an aspirator with air as the motive fluid to do this. These aspirators are available for industrial use and are known as "jets". They are made by Penberthy-Houdaille and others. I have used one as a pump using steam as motive fluid at work. Even the smallest of these (1/2" would be too big for your burner but you could get some design parameters from them and then make your own as you have your own industrial laboratory. This might be an effective sulfur fired torch.

My references also note that the exiting sulfur dioxide/oxygen ratio is important for efficient SO2 production. I believe that is why I was required to determine the oxygen content of the sulfur burner effluent using an Orsat analyzer at the sulfite paper mill I worked at a long time ago.

ozone vs health

DON'T GIVE UP ON COMBUSTION!!!

Burning a fine spray may not be as difficult as it sounds at first.

Have you ever seen those pneumatic cannon's people build out of PVC or steel pipe?

if not look at Slava's site... http://www.voltsamps.com


http://www.gizmology.net/airgun.htm
http://members.aol.com/sph911/spud/basic.html

anyway, they basically consist of a barrell, an air resevoir, a nipple to hook up a small air compressor (often a small 12V car compressor) and a ball valve to connect the resevoir to the barrel.

anyway, if you made the air resevoir large, fixed a filling port to the barrel to admit sulfur, wrapped a heating element around the barrell to bring the sulfur up to liquid temperature and made a tiny hole on the end cap covering the barell opening.......

you'd be in business my friend!

Thanks for the input. I don't really intend to use the ozone generator for anything, really.... I built it just due to the amusement factor.

And aaah, yes, spud guns. I built something similar once, only it didn't have a plastic, but a steel barrel, and it didn't use a fuel-air mixture as propellant but black powder, and it didn't shoot a potato but a lead ball, but the principle holds..

Using boiling sulfur to feed a nipple with a small hole in it much in the same manner as my propane burner works, perhaps without a fan even, might be worth some serious investigation. The brass nipple would have to be replaced with an aluminum one ofcourse.... and I shall need an aluminum rod, but... hmm. This is the perfect time to speculate, I'll probably make the exhaust heater today and the burner tomorrow.

Edit: I'm seriously considering using the boiling sulfur to pump gaseous sulfur through the burner nipple. I think I'm missing a caveat here though. Better think it through _really_ carefully.

Edit2: Ah. The caveat is the possibility of the boiler blowing up. Better put a burst diaphragm in there somewhere. It will also be a bit tricky to ignite the fuel-air mixture in a closed system.

Edit3: Off I go to get my heating coil!


[Edited on 2004-3-29 by axehandle]

[Edited on 2004-3-29 by axehandle]

[Edited on 2004-3-29 by axehandle]

What the fuck is wrong with my sulfur???

If the glove doesn't fit.......you must aquit.

OH.....

Don't worry, it happens to me all the time. It's always embarrassing though...

Edit: Well, I'm casting the plaster mold for the burner now. It will be shaped like a hollow cylinder, whatever the correct geometrical term for that is.....

Edit2: OK, this is REALLY weird. The sublimed sulfur didn't ignite either! Until I was about to pour it into a large bowl of water, that is. THEN it caught fire, right in the pot! I'm stupified.


[Edited on 2004-3-29 by axehandle]

[Edited on 2004-3-29 by axehandle]

Because, it eliminates one step from the process. I admit that I could just as easily ignite the molten sulfur by hand, but it wouldn't be as aesthetically pleasing....

I have one more card up my sleeve. A ceramic igniter (a heating coil embedded in clay, capable of making the clay rod glow). This is problematic for one reason: Where to draw the connection wires? I think I'll simply resign and do it the oldfashioned way, i.e. using a match...

My biggest problem is that I'm a perfectionist.

Edit: I'll go and finish my mold now...

Edit2: Note to self: Don't make a plaster mold in cookware with plastic handles. Drying it out in the oven without melting the plastic takes forever. I am an idiot.

Edit3: Very soon to reinstall win2k on this machine. Then it's ALUMINUM CASTING TIME!!!! YEAH!!!

Edit4:

Sulfur burners.

Yes, I've studied what I could find on the net, but I forgot about the digital library. Most of the burners I've found don't lend themselves to downscaling easily.

But tonight, I have cast the burner bottom! I didn't use gloves, but managed to only get one 1st degree burn. (And I set fire to the table when I spilled some glowingly hot Al on it --- easy enough to put out though...)

No pics of the burner bottom yet (it has to cool first) yet, but here's the result of pouring the Al leftovers into water:

Very artistic

Bottom done!

Here is the cast bottom, made of pure (99.9%) Al. It would look shinier if I polished it

The twisted thing inside is for distributing the heat better when the burner is in use.



Oh, and here is the inside:


Edit: I'll be going on vacation now for about a week. I may not have internet access.


[Edited on 2004-3-31 by axehandle]

[Edited on 2004-4-1 by axehandle]

First of all its is interesting and I at least find it self-rewarding you make something yourself. Buying stuff doesn't make me feel so happy as when I make it myself.

Secondly to avoid suck back he can use a set up as shown in the attachment. The use of an inverted funnel is stated when using gasses with a high solubility in water or other solvent. I think the diagram is self-explanatory. Oo btw, I think axehandle had already figuered out the problem, but just to give you an idea.

SO2 absorber

Back again from a tedious vacation.

But where I was, with little to no Internet access, I managed to get hold of some metal lathe time, a couple of pieces of aluminum, and threading tools in the mean time, so I made this between meals. It's an aluminum rod with a 5mm diameter hole right through it and with both ends threaded. I also made an endcap. It's meant for sulfur refilling the burner, and will simply by screwed in place in the lid once the latter is cast, drilled, and threaded.

The cap is simply a cylinder of aluminum, half drilled through and threaded by hand.




I also made this. It's a coil made from 0.5mm diameter Kanthal D NiCr wire, using a piece of 2mm thick welding rod, a drill press and lots of patience. There's about 25 meters of NiCr wire there. I intend to use it with the burner vessel for sulfur melting, coltrolled by a 150..160 C bimetal thermostat I ordered and which will arrive on Tuesday. The resistance of the coil is a whopping 75 ohms, which means that my burner pre-heater will use 645W, all automagically controlled by the thermostat (BTW, <b>this</b> is why I made the vessel so bulky --- to even out temperatures. Aluminum is my favorite metal. It's soooo wonderfully heat conducting, and easy to work with too. In case anyone was wondering )


PS: I'm glad to be back. Being without access to my 10Mbit line was horrible. It will also be very nice to talk to you all again.

How do you thread stuff by hand?

Saerynide: With HSS tools, patience and brute force . Anything can be threaded (well, as long as it's lower on the hardness scale than the tool, and not made of glass or something like that).

Tacho: Thanks. Now comes the hard part --- embedding the coil in a clay spiral for the integral burner heating plate *shudder*.

Edit: And oh, by the way, for the exhaust heater.... your amazing salt thermostat finally will be put to use!

Edit2: And as for how you get metal lathe time...: 1) Get a girlfriend who's father has his basement full of metal shop tools. 2) Fix his computer. 3) Suck up to him really good.

Edit3: BTW, I found this. I don't know if it works, but if it does it will come in handy for temperature calibration:


Edit4: I'm making more catalyst. Lots of it. My eye hurts from gaseous ammonia.... *sob*

Edit5: I've done some research on materials for the piping and couplings. The only realistic metal to use is Al, since it's completely impervious to hot SO2/SO3. Copper is heavily attacked. Unfortunately, it means I'll have to go and buy a very expensive 6 meter length of 10x3.0 pipe, as well as suitable threading tools. My wallet hurts....


[Edited on 2004-4-11 by axehandle]

[Edited on 2004-4-11 by axehandle]

Progress, progress.

I've cast half of the exhaust heater. In doing so, I managed to set fire to the table, the towel I grabbed the crucible handle with, and my welder's gloves.

It's the first and hopefully last time I'm forced to complete a molten aluminum pouring while on fire.

Pictures and a drawing of my intended manufacturing method will come as soon as the damned thing has cooled down, and I've stopped coughing. Hopefully none of my neighbours have called the police....


I'm seriously considering covering that table with alumina or firebricks.

Edit01: I think I (albeit being an idiot) still deserve some credit for managing to continue casting while on fire. I think most people would panic.

Edit02: I've decided against buying Al tubing. Instead I'll melt aluminum in an iron pipe (clamped at the bottom) and simply dip copper pipe in the molten Al. Then it becomes resistant to both SO2 and SO3, as well as H2SO3 and H2SO4. And I won't have to dehydrate the burner air! Now I'll make my drawing.

Edit03: Ok, here's the plan for the heater. So far I've done step 1:


Edit04: Here's the bottom part. It's 170x125mm and 10mm thick:


[Edited on 2004-4-12 by axehandle]

Sorry to clog your thread axe, but I've been messing around with FTP software, and I need a place to test a new way of uploading pictures, so I'm showing whoever reads this how the thermostat look like:



I must confess this FTP thing is new to me. I stopped my evolution at Turbo Pascal 7.0 for DOS. Did some nice real-time connections with the parallel (printer) port. They don't use printer ports anymore, do they? It's this USB thing now!

Ah! those were the days...

[Edited on 13-4-2004 by Tacho]

Good job casting while on fire Reminds me of the time I had to hold on a pot that was roasting on the stove for the last 10 min (with my bare hands ) because I didnt have a place to put it, and if i dropped it, Id have lost my dinner. My fingers where burned shiny... ouch....

Clay soluability etcetera

I've reached the same conclusion. However, if I were to mix the clay with copious amounts of NaCl or KCl, I might have a winner. The best thing would probably be to cast the entire spiral out of molten NaCl (MP ~= 800C), but this will be difficult, I'm afraid...

What I need is a material that's easy to shape, can take 700C without decomposing, and that is soluable in water. I have lots of thinking to do.

Been there, done that... more than one time

Thank you, and I will. Nothing short of death will stop me now!

(Jag SKA ha min jävla svavelsyra, hur lång tid det än tar!!!)

Thanks,

No probs Tacho,

we all make mistakes. Now, imagine how much fun I will have machining a 5x5 mm track along the black lines in this Al block using only a drill press and a hand file.....:


(That track is <b>1650mm</b> long! )

Edit: On second thought, I'll wait until tomorrow and buy the proper tool: An inverted cone rotating file.

[Edited on 2004-4-14 by axehandle]

[Edited on 2004-4-14 by axehandle]

Lots of holes.

The path is marked, now the only thing I need is a rotating file:

Btw: You're all right in guessing that drilling all those holes was no fun at all. Ooooh, my fingers ache.....

Edit: Homepage updated (finally...).

<b>Edit2: No, I'm NOT happy with the
shape of this track. </b> I'll RE-CAST it, in the same stainless oven form with the track
laid in the bottom using a bent 6x6 square
mild steel wire. Why the fuck didn't I come up with that idea earlier??? I'm a 1st class idiot.


[Edited on 2004-4-15 by axehandle]

Ouch. I would be crying if I had to trash all the hard work spent on that

[Edited on 16-4-2004 by Saerynide]

Try a solution of NH4NO3, this shouldn't be hard so to get ...

It'll may a while, but it should do the trick.

Good luck on the project, I'm a big fan

an alternative

Yes.

Use an aluminum pipe spiral, put water in it, then pour the Al block. the Al will solidify around the pipe. Then only Al will remain.

No propane. I'm gonna use electical heating (the Al block will be insulated within a block of refractory mix to avoid too great heat losses). Apart from that, you've read my mind .

edit3:

Thinking done.

Some success.

Had I known that burning sulfur is this complicated, I would have killed myself instead of starting this project. Now I must succeed. Sigh.

Edit: One thing springs to mind though. It's probably best to separate the burner into two devices: A sulfur melter (giving molten sulfur at a KNOWN temperature) and a sulfur burner.

The output from the burner can then be cooled to the right temperature in two ways: Water cooling to lower the temperature, increasing the rate of molten sulfur entering the burner to increase the temperature.

Edit2: There's one thing I'm going to try right away. Heating molten sulfur to its auto ignition temperature and see if contact with a Pt wire ignites it. If that works, I can keep my old design.

Damned, downscaling is HARD!

Edit3: Molten sulfur does not combust even at its auto-ignition temperature when exposed to Pt. Hah, my 1st real scientific result!

Edit4: It's 01:25 here and I just cast the lid for the melter/burner. How? I filled the cavity almost to the top with anhydrous NaCL, put two copper pipes where they were supposed to be, and strapped copper sheet around the top of the vessel, forming an edge around the top. Then I just poured Al in there. Only thing that remains is drilling and threading the refill nipple hole, and ofcourse flushing out the NaCl using water.

Pictures will follow as soon a the thing has cooled down. I love casting aluminum.

No fires this time though.... pity .

Edit5: <b>I'll keep my old design,</b> btw. One time throw-away NiCr igniters, screwed into the lid, will do just nicely.

[Edited on 2004-4-20 by axehandle]

[Edited on 2004-4-20 by axehandle]

Nope, failure.

The lid isn't airtight. Probable cause: Thermal expansion of the bottom half as a result of the lid being poured, then thermal constriction as it all cooled.

Tomorrow I'll do something fun (this is irony): I'll glue sandpaper onto a table and sand the edge of the bottom perfectly even. Then I'll cast a circular aluminum plate with the same diameter and sand that one as well. Then I'll drill, thread, and put a hinge on, so that the lid can be opened and closed easily. That <b>should</b> make an airtight, or almost airtight, seal. And it that doesn't work, I'll <b>weld</b> the little fucker in place. Or perhaps make lots of holes around the edge, thread them and then <b>bolt</b> the damned thing in place. I've never met a piece of Al that does not yield to a 8/8 M10 bolt.


Here's the vessel with failed the lid on:


and here you can see the failed lid (the depressions in the center are due to the NaCl crystals I filled the bottom with prior to casting:


Blast.


[Edited on 2004-4-21 by axehandle]

I don't mean to come off sounding like a dickhole...but...

I stand corrected on the matter of SO2/SO3.

I got the joke, and yes I'm mad. Or perhaps insane. But c'mon, there's a <i>reason</i> I'm using Al in huge quantites: Lead would melt, stainless steel is a pain to work with, and most everything else is either 1) corroded by molten sulfur and/or SO2 or 2) ceramic (I hate ceramics) or 3) expensive as gold. Literally.

And Hermes, I can't speak for all Swedes, but there's no way I'm going to put my <b>back</b> into it. My back is very bad. I will put my arms into it though..... Masturbation works wonders as workout.

Edit1: I'll explain my design by stating the design goals later, right now I have to go and see my probation officer.


[Edited on 2004-4-21 by axehandle]

Design goals.

See design goals 1, 2, 3 and 12.

OK, here are my design goals:

1) Safety.

2) Safety.

3) Did I mention safety?

4) Compactness. The maximum allowable
size of the machine is 500x500x500mm.

5) Modularity. All parts should fulfill 1
function only, and be easy to replace.

6) Longevity. The parts should withstand
at least 1/2 year of continous use.
Notable exception: filters, which must be
easy to replace.

7) Automation. The machine should be able
to run unattended, shutting itself down
immediately if any alarm thresholds are
exceeded.

8) Availability of materials. With the
exception of the catalyst, anyone should
be able to duplicate the machine with a
minimum of raw materials. Other
catalysts can be employed, however. I
chose V2O5 because 1e06 chemical plant
engineers can't be wrong.

9) Minimization of ancilliary feeds. In English,
the machine must run only on water,
electricity, air and sulfur. Its only waste
products should be heat, air, water, SO2,
and H2SO4. The last one isn't technically
a waste product, but I list it here anyway.

10) Efficiency. At least 80% of the generated
SO2 must be converted to SO3.

11) Leaklessness. The machine must be able
to run indoors.

12) Safety. Didn't I mention this before...?

Those are the major design goals. I will take
no shortcuts, and under no circumstances
violate design goals 1, 2, 3 and 12.

Edit: Can't do much right now, lack these tools in M16 size, as well as Al round bar:



Will buy the tools and roundbar tomorrow (together with more Al plate to melt.... )

Yes, I'm going to make my own Al pipe sections. Only way to be sure the walls are thick enough. Gaseous SO3 at 500C would
be like gaseous chainsaw..... *shudder*.


[Edited on 2004-4-21 by axehandle]

In hindsight I did forget one thing

A small victory for mankind, but a great one for me.

Aquisition.

What's in the picture, and a thermostatically controlled hotplate I just couldn't resist buying considering how much work it will spare me.

Plus 10kg of powdered SiO2, and 1kg of bentonite clay. Now I only need a bottle of motor oil, then it's sand-casting time.

The only problem is: What am I supposed to eat for the next 5 days? This set me back about 70 Euro.....

EDIT1: I'm considering returning the M16 sized cutters and get M20 instead. Better wall thickness. Perhaps even M22.
EDIT2: Nah, I'll keep them AND get M20 dies.



[Edited on 2004-4-22 by axehandle]

[Edited on 2004-4-22 by axehandle]

How about powdered gypsum