Sciencemadness Discussion Board

DIY distillation app

postart - 2-3-2011 at 12:52

hello, I have been thinking about how one might construct a distillation/reflux apparatus DIY. The apparatus would be for chemistry not brewing so it would have to be resistant to strong acids, bases, Cl, Br and so on. I'm not a glassblower or welder and am trying to figgure out something that the average DIY chemist in need could replicate. All I could find on the net was for brewing equipment. I was wondering if there is some sort of teflon spray in a can that could be used to coat steel rendering it chemical resistant. I thaught of a pot with the lid sealed on with heat resistant epoxy then use metal tubing. Im not quite shure how it would all hold up no more than aspirator pressure would be applied to the apparatus. Any ideas would be great or better yet has anyone done this before themselves?

smaerd - 2-3-2011 at 13:11

Honestly a 24/40 glass distillation set up would cost around $100 and would be sure fire. The beauty of the glass also is you can reflux, do vacuum distillations, stir through it, add on to the set up, etc. I wouldn't ever substitute a good glass set up.

I'm not to sure about your question though, so sorry if this post is irrelevant.

Bot0nist - 2-3-2011 at 13:14

For strong acids and such you'll need some Pyrex glassware with all glass tubing for a condenser. As for the joints, rubber won't work unless you don't mind eating them up and adding contaminates to the product. I think some members have had luck with Teflon tape at the joints. IMO save up a bit and get one with ground glass joints and a nice condenser. unitednuclear.com has a nice one for sale. $120 us I think for the 500ml setup. $200 for the 2000ml setup.

Search some of the HNO<sub>3</sub> distillation threads. I think it is discussed a lot there.

[Edited on 2-3-2011 by Bot0nist]

cyanureeves - 2-3-2011 at 14:04

most of your stuff will be contaminated if you use steel.epoxy will find its match eventually and escaping fumes can mess you up and your surroundings.trying to find glass that is bent and can be used for condensing or to channel distillates is almost impossible.look at the price for bent adaptors!there is almost nothing out there that can be used in its stead and acids will find cracks you cant even see on porcelain coated pots so thats ruled out.

postart - 2-3-2011 at 14:08

Thanks for the replies I think I'll start saving to save myself a headach.
BTW can a distillation condencer also be used as a reflux condencer without modification?

Magic Muzzlet - 2-3-2011 at 14:11

Don't buy the united nuclear distillation kits, they are basically useless along with the condenser that comes with it. If it was the other type of Graham condenser it might be useful to an extent but it is not good for very much at all.
I made this mistake when i bought one, better off buying from UGT or something.

Bot0nist - 3-3-2011 at 06:49

Magic Muzzlet, can I ask what problems you had with your distillation apparatus or condenser? Leaks? All the glass I have gotten from them has been acceptable.

[Edited on 3-3-2011 by Bot0nist]

Magic Muzzlet - 3-3-2011 at 08:35

The type of condenser can't be safely used for reflux and it is sometimes a pain to distill certain things with the downward configuration and all. If you get a RBF, adapter and then use the condenser it builds up pressure and is just a pain in the ass. It is better to buy a proper setup with a better condenser than to buy the odd united nuclear flask and condenser.
I feel this way because when vacuum distilling and fractional distilling you can't use the setup from united nuclear anyway, can't use the condenser really either, so I feel it is a waste.

hissingnoise - 3-3-2011 at 08:42

Quote: Originally posted by postart  

BTW can a distillation condencer also be used as a reflux condencer without modification?

Some people run coolant through condensers during reflux!
For use with high-boiling liquids they should be air-cooled to avoid undue thermal shock . . .


Bot0nist - 3-3-2011 at 08:46

@Magic Muzzlet
Thank you. So you recommend UGT. I have used U.N.'s setup, but really only for ethanol distillation. I did have trouble condensing HNO<sub>3</sub>, but I had attributed that to operator error. What you say makes sense. I will check UGT's prices out today, and thanks again for the testimonial.

[Edited on 3-3-2011 by Bot0nist]

Magic Muzzlet - 3-3-2011 at 08:50

No problem, also keep in mind that eBay often has very good deals on glassware too. There are a few sellers that often have Pyrex and chemglass items at reasonable prices and great condition, always something to keep an eye on. ;)

hissingnoise - 3-3-2011 at 08:55

I got a fritted funnel from UGT years ago---it turned out to be Wilmad!

Good supplier!


bquirky - 3-3-2011 at 09:01


only the inside of the condeser has to be glass..

what if you got a glass tube and ran it down the length of a peice of pvc piple with two endcaps with silicone drilled holes to let the glass tube through

i guess you whould still nead to use a rubber cork.. but there disposable.


Chaoschemist - 3-3-2011 at 09:10

Quote:
The apparatus would be for chemistry not brewing so it would have to be resistant to strong acids, bases, Cl, Br and so on.

You should probably think about what you want your set up to deal with.
Even if glass is the most usual (not completely, but it should be usable for most purposes) material for chemical experiments" other materials should be fine.
If you're trying to distill e.g. organic solvents a copper distillery (DIY, or bought however) could do it.
Further usage of metal-condensers is necessary while refluxing over hazardly moisture-sensitive set ups, to prevent every failure with leakage of water into the apparatus (Drying solvents over elemental sodium)
Further if you wont waste to much water, or, how already mentioned, you're going to distill a high-boiling substance, an "air condenser" is necessary.

[Edited on 3-3-2011 by Chaoschemist]

[Edited on 3-3-2011 by Chaoschemist]

hissingnoise - 3-3-2011 at 09:31

I just cannot understand why people continue to fuck around with stoppers, teflon tape, alufoil and that shit when a simple all-glass apparatus costs a few euro . . .


1281371269 - 3-3-2011 at 09:53

You don't need to buy a complete kit. If you have some patience, you'll save yourself a lot of money by constantly checking eBay until real bargains come up. Of course, if you don't want second hand stuff then it will be considerably more expensive.

Chaoschemist - 3-3-2011 at 09:54

Fear of breaking it?
In case of a larger setup/speciality cooking (e.g.pyrolysis) it could be recommendable to use alternative compounds than glassware, but I guess nobody expects to make extreme huge apparatuses, simply due to the increasing requirements in safety issues.

Melgar - 4-3-2011 at 00:25

For temperatures below 150C or so, I've built a distillation set out of empty glass wine bottles/jugs and had it run fine without breaking. I did have to buy some rubber stoppers from the brewing store (which I glued in place with silicone caulk), and also had to buy some pyrex tubing and a digital thermometer. Granted, this glass will crack if exposed to sharp thermal gradients, so whenever I used it I always set it up cold, put the bottle I was heating in an oil bath, then slowly turned up the heat until it was the right temperature. I wouldn't move anything if I could help it until after it all cooled off either. This worked pretty well for stuff like nitric acid, ether, toluene, ethanol, etc. I even had a reflux column filled with pieces of broken glass.

I never applied a vacuum to it, but it wouldn't be impossible. Just bore a second hole in the stopper on the receiving flask, then hook a really short piece of glass tubing going from the hole to one of those brake line bleeders. Of course, I wouldn't trust this setup to withstand more than about a 5 psi drop in pressure below atmospheric, unless maybe I was distilling water and had on lots of protective gear. I liked this setup because if I cracked the "flasks", they were pretty much free to replace.

I can draw a diagram if anyone's interested.

a_bab - 4-3-2011 at 03:21

In some organic synth russian chemistry book champagne bottles are cited as being good for high pressure reactors (up to 20 atm), protected by a metal tube.

cyanureeves - 4-3-2011 at 06:55

o.k. i use a european gravity coffee maker to make sodium nitrate from ammonium nitrate and bubble the ammonia through water.i got a couple of coffee pots that look like erlenmeyers and will probably work as erlenmeyer flasks.there is this video on youtube of a guy making nitric acid with a stainless steel distiller.if this video is real then the acid must be condensing before it can dissolve the steel.someone wrote that s.steal forms a passivation layer that keeps it from reacting but i doubt his acid is clean.i would'nt mind having a long glass tube to attach to my glass retort spout for better condensation.

postart - 8-3-2011 at 18:06

Hay I'm looking around the web at glassware and had a question. Are distillation and reflux condencers the same thing, or do I need a distillation condencer and seperate reflux condencer? as long as everything is 24/40 the condencer should work for distillation and refluxing, right?


Thanks!

cyanureeves - 8-3-2011 at 18:47

the reflux condensor looks totally different.i bought an allihn condensors because i thought the bubbles would help more with the condensing as opposed to just a straight tube like the famous liebig condensor and i saw a picture of someone using it as a reflux condensor.the allihn has to be used in a straight down position if used as a condensor or the distillate will get trapped in the bubbles and the liebig can be used in an angled position and still work.i wanted the graham condensor but its expensive. i still havent used the allihn and was a bit disappointed at first when i saw it used as a reflux condensor because i wasnt looking for a reflux condensor.the more experienced will answer your question better and i will be feeding off it as well.

ScienceHideout - 13-3-2011 at 07:51

If you get ground glass, size 19/22 is better than 24/40. Though a bit harder to find, it is smaller and easier to work with, not to mention cheaper.

redox - 13-3-2011 at 16:20

Quote: Originally posted by bquirky  

only the inside of the condeser has to be glass..

what if you got a glass tube and ran it down the length of a peice of pvc piple with two endcaps with silicone drilled holes to let the glass tube through



I did this a little while ago (before I got an actual apparatus). Just do what you said, drill two holes in the pipe, and silicone caulk two lengths of glass for icewater flow.
This setup works fine for crude distillations, and pretty easy (and cheap!) too.


cyanureeves - 13-3-2011 at 17:47

not bad redox and bquirky. by the way you do know that is the way to make a sound suppresor?with the addition of holes in the center tubing(and up to 20yrs. in the penn).but that aside what would ya'll suggest for a bent adaptor?i mean one could find a boiling vessel even if only for one time use and you just came up with that condensing tube. but how would you go about hooking them up?

cyanureeves - 13-3-2011 at 18:23

also i know my question is not about distillation but it is about DYI. i rigged up a stir em up contraption with a fan and a big ole magnet and it spins a screw pretty good in a water filled jar. i got it set on a wooden box i made and have to toy with the height or it will spin a vortex until it makes a toilet flushing sound and acts all stupid. now i need a stir bar so i got a headless screw suspended in some silicone rtv and i'm thinking of shaving it into shape tommorrow or whenever it cures.i dont know if silicone would be right for an acetone and hypochlorite mixture as in chloroform,or even hydrazine synthesis.last time i made chloroform i swirled it around myself in freezing weather and that sucked!what can serve as a stir bar for now until i get some money to buy one? thank you very much.

Arthur Dent - 14-3-2011 at 04:47

Quote: Originally posted by cyanureeves  
what can serve as a stir bar for now until i get some money to buy one?


I completely support home chemistry and I commend people who create cool DIY apparatus and home-brewed gear, but I think there are limits to McGuyver-isms...

A stirbar can be had for as little as $2 on Ebay, and most hobby shops and online science/hobby stores have these for even less! Surely you can spare a few bucks for proper gear?

Your idea, however commendable, has a few flaws. Even cured, the silicone rubber will not glide and slide properly at the bottom of your flask/jar. So it will probably bump and rattle out of control, not really mixing anything. Plus most mason jars and condiment jars have a bottom surface that is not flat, but slightly domed upwards... which again is not a friendly environment for a stirbar. I strongly suggest that you use a jar with a flat or recessed bottom, and that you do not use a screw dipped in goop!

A suggestion for an alternative stirbar is to use a bit of glass tubing about an inch long, find a nail that fits the bore snugly, clip both ends of the nail to a bit over 1/2" and then heat seal both ends with a torch... VoilĂ ! A stirbar that is impervious to any chemical attack, but be careful when you "drop" it in a jar as it will be quite fragile.

Robert

food - 14-3-2011 at 09:23

Something that I've been doing is to mate my bona fide glass condenser to larger glass jugs with sections cut from bicycle inner tubes. Depending on the diameter of the jug mouth the length of tube can be a simple ring or a longer piece doubled back on itself. Typically I'll do this with a 160 fl oz glass jug.

I've not done this with anything involving particularly aggressive chemicals or temperatures. It's just occurred to me that the rubber could be isolated with teflon tape.

The base of the jugs that I have aren't flat, but stirring with a magnetic stir bar has been working.

I'd thought about adding that to the thread about lab tips. Inner tubes are a great resource, and are there for the asking. Only a couple of weeks ago I saw a shop display of locally made accessories (for the fairer sex) manufactured from inner tube material. A kind of gritty gothish look.

cyanureeves - 14-3-2011 at 17:36

if you're going to use rubber then that so called space age rubber looking material used for cooking should work better. it's starting to show up at resale shops and flea markets more and more because older people don't like it. i got a couple strown around in my tool shed.

food - 15-3-2011 at 09:36

Quote: Originally posted by cyanureeves  
if you're going to use rubber


not so much a goal, but it's been a handy setup for volumes too large for the flasks that I have

Quote: Originally posted by cyanureeves  

then that so called space age rubber looking material used for cooking should work better. it's starting to show up at resale shops and flea markets more and more because older people don't like it. i got a couple strown around in my tool shed.


Isn't that material silicone? Some possibilities there; a section of a glove finger might do the same thing as my inner tube piece.

I may be one of those older people. It did strike me as an odd material to be involved in the cooking or baking process. I haven't tried it yet.

quicksilver - 18-3-2011 at 09:21

This perhaps one of the better "home manufactured still" design manuals and goes into detail quite explicitly.
Revamping this to handle corrosive materials would be very simple (a switch in materials, etc) and offers a very expedient method of working with non-corrosives, as is
.


Attachment: Ethanol_still_design.pdf (1.5MB)
This file has been downloaded 1022 times


food - 22-3-2011 at 17:25

Quote: Originally posted by quicksilver  
This perhaps one of the better "home manufactured still" design manuals and goes into detail quite explicitly.
Revamping this to handle corrosive materials would be very simple (a switch in materials, etc) and offers a very expedient method of working with non-corrosives, as is
.


it's funny that you should post that. I made a still from this design, with some minor modifications.

I ran it this time with an oven thermometer probe through to the side-arm takeoff. Before now I've used a glass thermometer, but it's mercury, and I've been getting nervous about mishaps. Works like a hot damn. Used it for ethanol so far. I have a proof hydrometer and iirc it's around 95%.

The stainless steel stock pot lid has a copper union(?) attached. The column drops into that; not permanently attached. The weight of the column pretty much seals the lid of the stock pot. I've done different things for that. Typically draping heavier teflon tape around the edge. I think that the last time I just put the lid on and went naked.

Made the feed material from a crude (and cheap!) sugar sold in east indian stores. Comes in a large block. My thinking is that we're looking at a material that is rich in nutrients. No need to fret over special 'turbo' yeast products. It's very crude; bugs, everything; jaggary. Lavalin EC-1118 provides a moderately alcohol tolerant yeast for higher initial alcohol. Last time I froze a huge mother pail of the fermented stuff to achieve an even higher alcohol %, and lower volume.

sorry about the mess (standard disclaimer, girls)

still.jpg - 210kB

Arthur Dent - 23-3-2011 at 04:33

@ food: Nice work mate! Been thinking about doing something of that sort, but for now, my strong spirits still consists of two boiling flasks, a claisen adapter with thermometer and a pyrex graham condenser. I'm strictly small production, and the only time I pull out the big 5 gallon glass bottle is when I brew beer.

I have part of my glassware collection that's dedicated only to make ethanol for consumption. It's either been bought new or has been treated thoroughly with acids and cleaned extensively. I don't use that glassware when I work with heavy metals like manganese, nickel and copper.

Robert

quicksilver - 23-3-2011 at 06:34

It (the design) does indeed work. I have used a very nice 2 liter kit that came in a briefcase for some years but needed to make some chloroform and other odd and ends so I tried out the design and liked it too.

Hennig Brand - 15-10-2011 at 07:30

@food
That is a really nice ethanol still. I don't think anything like that is used for distilling HNO3 normally though. A column could be used industrially to bring dilute HNO3 up to the azeotrope (~68wt% HNO3) I guess before using dehydrating agents to bring the concentration up past the azeotrope.

I think for the hobbyist a nitrate salt, or sometimes dilute HNO3, is normally added to H2SO4 and distilled to give concentrated or greater than concentrated HNO3 directly using a pot still basically (no column).

Just for fun last night I played around with an improvised set up for distilling HNO3. The basic design is nothing new; I have seen similar things done in several different places. I used 40g of AN and 25mL 90% H2SO4. I collected ~23mL of ~60wt% HNO3 (wt% determined from density and tables). I didn't get a great yield, but in an hour with this very simple set up it is possible to get a little acid to play with. Except for the beaker all the other components were just things that were lying around (household items, not lab items).


HNO3 Distillation.JPG - 361kB HNO3 60 Percent.JPG - 255kB

BTW, the stem on the wine glass thing I am using for my distillate receiver is really too thick. A thinner stem would have greater thermal resistance, which would result in less heat transfer between the lower boiling area and the receiver cup.

Some of the ideas above for an improvised Liebig condenser would make for a much more productive set up. As suggested glass tubing could be run through a plastic water jacket to make the condenser. Any glass flask that will handle being heated could be used for the boiling vessel. A nice teflon stopper could be turned on a lathe (find a piece of teflon and get someone with a lathe to turn it into a stopper shape. The stopper and the hole in the center could be sized in such a way that teflon tape could be wrapped around the glass tubing to make it fit the stopper hole and around the outside of the stopper to make it fit the flask (boiling vessel). This setup should work well, I think.


[Edited on 15-10-2011 by Hennig Brand]

unsub - 23-10-2011 at 17:07

Hello all this is my first post. I have a couple old style flasks etc and was considering buying the condensor to go with them but will probably just splurge for ground glass so the comment about 19/22 is interesting. I like the idea of "juryrigging" a kit together though and like the PVC condenser which I suppose could be quite long if need be. My idea for home built 3 neck reaction flask would have pyrex casserole dish bottom ,teflon tape gasket with a flat piece of stainless steel with your 3 holes "C" clamped together. The steel could be painted with teflon paint and you could even fit the holes with stainless pipe carefully dremelled to 19/22 or 24/40 and use it with actual ground glass. I would want room to wrap the glass in teflon tape though. I don't want to spend a week of evenings on the steel lid if there is an obvious flaw I have missed?

The question of hooking up the glass tube of the PVC condenser would be simple if not to corrosive since you could just use rubber stoppers and silicon tubing. For corrosive chemicals on a budget I would steal an idea from vogels and use a cork stoppr wrapped in aluminum foil(very carefully) to connect the glass tube from the condenser to the stainless and teflon reaction vessel.

Another idea I have been toying with is using a clear glass teapot as a makeshift buchner flask. Attach the vacuum hose to the spout.

Lambda-Eyde - 23-10-2011 at 17:20

Quote: Originally posted by unsub  
The steel could be painted with teflon paint and you could even fit the holes with stainless pipe carefully dremelled to 19/22 or 24/40 and use it with actual ground glass.

There's no way you'll get a remotely good seal without using a precision lathe.

I don't get it why some people actually are willing to pour hours of thinking and MacGyvering into projects like these when a three-neck RBF can be had from eBay at quite reasonable prices (and you're sure it will work).

Welcome, by the way.

unsub - 23-10-2011 at 18:47

Thank you lambada-eyde for the welcome.

I enjoy "macguvering" as an end in it's self and totally agree that simply ordering a proper flask is much much more efficient use of time. It is also a safety hazard with some chemicals.


However depending where you liveordering glassware and chemicals invites a lot of scrutiny from the secret police. I like to think that making a distillation kit from everyday items would prove to the powers that be that there is no point in banning or restricting laboratory glassware.

I like coffeemaker pots for beakers since they can handle heat. Mine even has marked graduations although I should write out a metric to "cups of coffee" scale.

I disagree about not getting a good seal though. I make knives as a hobby and can fit pieces together so a layer or 2 of teflon tape can easily seal it. If I can make something out of mostly recycled consumer goods that is worth some extra effort and if some politician says we shouldn't have one then it's a matter of principle.

zgoat65 - 27-1-2012 at 17:14

If someone lives in the Lone Star State, one 5000ml three-neck flask with no chemical present for a mile can aquire someone an all expense paid vacation (for ten years ) at one of the lovely state funded resorts. Just the glass can get you a case.

[Edited on 28-1-2012 by zgoat65]

entropy51 - 28-1-2012 at 08:27

Quote: Originally posted by zgoat65  
If someone lives in the Lone Star State, one 5000ml three-neck flask with no chemical present for a mile can aquire someone an all expense paid vacation (for ten years ) at one of the lovely state funded resorts. Just the glass can get you a case.

[Edited on 28-1-2012 by zgoat65]
Can you give an example of that law being used to convict someone who wasn't actually making illegal drugs? I don't think it has been done.

zgoat65 - 2-2-2012 at 10:26



[Edited on 28-1-2012 by zgoat65][/rquote]Can you give an example of that law being used to convict someone who wasn't actually making illegal drugs? I don't think it has been done.[/rquote]

Here is a useless link that gives some opinion and truth on the law in my fair state. http://thegoodreverend.blogspot.com/2006/04/texass-anti-lab-... .
While I have found nothing on a conviction of anyone
possessing lab glass alone, most had p2p or multiplereagents in town with the glass. I will say that they most undoubtedly charge uou with a crime, and possibly with intent to manufacture. I was charged with possession of chemicals with intent for having camp fuel, drain cleaner (sulfuric), and brake fluid (never understood this) in a vehicle I was a passenger in (and all but one chem in the trunk _ie drain cleaner) with an explanation for all itens, they still charged the drivera and myself with a crime and had to post a 10000 dollar bond. While the case was thrown out due to it. being stupid I still had to fork out 1000 dollars to maintain my freedom, as well as having this arrests show up on any future background check. CAN they convicted on on basic possession of lab glass? I hace no clue. Will they try? The answers is YES!

zgoat65 - 2-2-2012 at 11:22



[Edited on 28-1-2012 by zgoat65][/rquote]Can you give an example of that law being used to convict someone who wasn't actually making illegal drugs? I don't think it has been done.[/rquote]

Here is a useless link that gives some opinion and truth on the law in my fair state. http://thegoodreverend.blogspot.com/2006/04/texass-anti-lab-... .
While I have found nothing on a conviction of anyone
possessing lab glass alone, most had p2p or multiplereagents in town with the glass. I will say that they most undoubtedly charge uou with a crime, and possibly with intent to manufacture. I was charged with possession of chemicals with intent for having camp fuel, drain cleaner (sulfuric), and brake fluid (never understood this) in a vehicle I was a passenger in (and all but one chem in the trunk _ie drain cleaner) with an explanation for all itens, they still charged the drivera and myself with a crime and had to post a 10000 dollar bond. While the case was thrown out due to it. being stupid I still had to fork out 1000 dollars to maintain my freedom, as well as having this arrests show up on any future background check. CAN they convicted on on basic possession of lab glass? I hace no clue. Will they try? The answers is YES!

Hennig Brand - 2-7-2014 at 06:57

I forgot about this thread and made a post about a simple homemade glass distillation apparatus made from common flasks and materials in a nitric acid synthesis thread. It fits in that thread too though I guess.
http://www.sciencemadness.org/talk/viewthread.php?tid=2176&a...

Hennig Brand - 15-7-2014 at 12:28

I made a few changes to the simple still I posted pictures and a description of in the nitric acid synthesis thread. A thermometer port (hole) was added (drilled) into the Teflon bushing on the Erlenmeyer boiling flask. A bushing was also added to the receiving flask as well as a small centrifugal pump so that a constant supply of cool water could be made to flow over the round bottom receiver. A small diameter glass tube was used to vent the system and prevent buildup of pressure or vacuum. The vent tube's open end was kept well away from the water bath and flowing water so as to reduce absorption of moisture by the produced nitric acid.

It works extremely well. The thermometer in particular is a very valuable addition. Depending on the way you look at it, the old quantity versus purity trade off, I botched the distillation. To produce the HNO3, 480g of NH4NO3 and 300mL of 91% H2SO4 were used. I ended up with a rather large volume of distillate (234mL), but it titrated at only 82wt% HNO3. For the last 45 minutes or so of distillation the temperature of the vapor sat right at about 120C. When it hit 120C is when I probably should have made the cut. Oh well, I have more acid now, but it does need to be redistilled with concentrated sulfuric acid if I want over 95wt% acid. The sulfuric acid was drain cleaner that titrated at only 91% and the ammonium nitrate used was fertilizer prills and looked and felt a bit damp (should have been dried).

A significant amount of cooling can be had through evaporative cooling, with this arrangement, if the cooling water only needs to be kept slightly above the wet bulb temperature of the ambient air.

The bushing on the receiving flask is not Teflon, but is a bushing I made from a random piece of plastic round stock found at a scrap yard before I got a piece of Teflon. It is very resistant to nitric acid, only showing very slight blistering when used on the nitric acid boiling flask for several hours. I used it on the boiling flask a year ago or so. I tried yet another piece of plastic round stock from the same scrap yard and it turned to bubbly, tar, goop in about ten minutes on exposure to hot nitric acid. I don't know what either of the plastics are, but it is easy to tell that they are different from Teflon and each other by the way they cut and drill, etc, on the lathe.

Showing off my recently made homemade electric kiln in the pictures. :)

Pre-Run.jpg - 253kB Still Running.jpg - 275kB
Condenser & Receiver Flask.jpg - 246kB Nitric Acid Product.jpg - 405kB

Just for the hell of it 4mL of the newly distilled nitric acid was mixed with 8mL of 91% sulfuric acid and used to nitrate 2mL of glycerine. The glycerine was added to the mixed acid in a 50mL beaker drop wise from a pipette with swirling and then covered in plastic wrap and left for an hour and a half at room temperature out of the sun. The yield was surprisingly about 2mL of NG from 2mL of glycerine. A lot of the acids I have used in the past were probably not nearly as concentrated as I thought they were.


[Edited on 16-7-2014 by Hennig Brand]

Hennig Brand - 20-7-2014 at 08:01

Sorry for the multiple posting, but I have a small correction for the above post. The receiving flask used was actually a Florence flask, not a round bottom flask as was previously stated. The longer neck of a Florence flask may actually be better in this case as compared to the normally shorter neck of a round bottom flask. I guess some round bottom flasks do have long necks as well though.

Yeah, the end of that vent tube probably shouldn't end where it does either. I was at a different location entirely when I cut the piece of tubing and guesstimated the length.

[Edited on 20-7-2014 by Hennig Brand]

Hennig Brand - 26-8-2014 at 08:13

Found a really good webpage with information regarding recovery, concentration and purification of mineral acids. I attached an image of the nitric acid graphs, which I thought would be very useful for someone synthesizing or concentrating nitric acid (distilling).


http://www.ddpsinc.com/de-dietrich-services

Was having a little trouble linking to the exact page; the link above is a couple clicks away from the page on mineral acids. I made a pdf of the mineral acids page and attached it below.


Nitric acid Concentration & Vapor and Liquid Temperature Diagrams.png - 72kB


Attachment: Recovery, Concentration and Purification of Mineral Acids DDPS.pdf (341kB)
This file has been downloaded 676 times


[Edited on 26-8-2014 by Hennig Brand]

Hennig Brand - 11-12-2014 at 08:04

The following is the bit of text which preceded the graphs which where attached in the last post.

"The diagrams below (show) the impact of different sulfuric acid concentrations to the azeotrope point. Azeotrope disappears beyond a sulfuric acid concentration of 50 wt%, yet for technical rectification, an acid concentration of about 70 wt% is to be targeted."

I made an Excel spreadsheet this morning which I think will be a decent tool to use when concentrating nitric acid using sulfuric acid to break the HNO3/H2O azeotrope. To simplify, all water was assumed to remain in the boiler; when this becomes significantly inaccurate can easily be determined by referring to the vapor-liquid equilibrium diagram included with the spreadsheet.


Attachment: Concentrating HNO3 - Overcoming the HNO3_H2O Azeotrope Using H2SO4.xlsx (79kB)
This file has been downloaded 413 times

Attachment: Concentrating HNO3 - Overcoming the HNO3_H2O Azeotrope Using H2SO4 (compatibility mode).xls (97kB)
This file has been downloaded 453 times


chemrox - 11-12-2014 at 22:27

Quote: Originally posted by hissingnoise  
I just cannot understand why people continue to fuck around with stoppers, teflon tape, alufoil and that shit when a simple all-glass apparatus costs a few euro . . .


Me too! I worked with a geophysicist that liked to make things .. as an example he bought $2 worth of mesh and spent an evening sewing a mosquito hood. I bought one made well enough to exclude the little bastards for $4.50. These are apparatus hobbyists and people who devalue the worth of their time. I was getting a day rate so time spent fucking around with gear was money stolen from the client.

Hennig Brand - 12-12-2014 at 03:40

Sounds like kind of an extreme example. ;)
Well, I think learning the simple skill of making Teflon bushings, allowing the hobbyist to make their own safe and reliable distillation and other equipment while eliminating or significantly reducing the need for glassblowing, is very worthwhile. Plus if the situation ever arises, you will have developed a skill set which allows you to actually do things in the absence of a lot of the modern commercially produced chemistry equipment. Not only is learning to work with Teflon and glass a useful skill it is also the kind of thing mad science, or Sciencemadness, is all about in my opinion.

I have a small assortment of Teflon rod, sheet and other assorted pieces now from which I can draw on to make a variety of fittings and other components for mad science type activities. :)

Anyway, the information from the last couple of posts is useful whether or not distillation is performed in a commercially produced ground glass, all glass, apparatus or a homemade distillation apparatus.


[Edited on 12-12-2014 by Hennig Brand]

confused - 12-12-2014 at 05:59

Quote: Originally posted by cyanureeves  
also i know my question is not about distillation but it is about DYI. i rigged up a stir em up contraption with a fan and a big ole magnet and it spins a screw pretty good in a water filled jar. i got it set on a wooden box i made and have to toy with the height or it will spin a vortex until it makes a toilet flushing sound and acts all stupid. now i need a stir bar so i got a headless screw suspended in some silicone rtv and i'm thinking of shaving it into shape tommorrow or whenever it cures.i dont know if silicone would be right for an acetone and hypochlorite mixture as in chloroform,or even hydrazine synthesis.last time i made chloroform i swirled it around myself in freezing weather and that sucked!what can serve as a stir bar for now until i get some money to buy one? thank you very much.


Not sure if this will work, just throwing an idea out there, but a paperclip might work

smaerd - 14-12-2014 at 22:03

Quote: Originally posted by Hennig Brand  
Well, I think learning the simple skill of making Teflon bushings, allowing the hobbyist to make their own safe and reliable distillation and other equipment while eliminating or significantly reducing the need for glassblowing, is very worthwhile. (quote trimmed for space)

[Edited on 12-12-2014 by Hennig Brand]


Hennig could you type something up or show some examples of the teflon bushings/glass-teflon connection you have made? I think a lot of us could really benefit from it.

Hennig Brand - 18-12-2014 at 13:45

No problem, I posted the following in the "nitric acid synthesis thread". There are also a couple of pictures of the Teflon bushing made (the bushing could have been made much more neatly if more time was taken and more attention was paid to detail). Once one has Teflon round stock of an appropriate size, and access to a lathe or someone who has a lathe and doesn't mind taking on small jobs, it is very simple. Here is a link to where the following quote was originally posted:

http://www.sciencemadness.org/talk/viewthread.php?tid=2176&a...

Quote: Originally posted by Hennig Brand  
Here is a very simple little glass still I made a year or so ago from common flasks without ground glass joints. The most important part of the apparatus is the Teflon bushing, which can be easily made on a lathe from Teflon round stock of an appropriate diameter. Two approximately eight dollar flasks were used and a piece of glass tubing obtained for free. A piece of Teflon round stock was purchased for $30 which provided enough material for 4 bushings. The center hole of the bushing was bored out slightly oversized and the outside diameter of the section which would slide into the flask was made slightly undersized. This allowed the glass tubing and outer diameter of the bushing to have many wraps of Teflon tape applied so as to give some of the elasticity that would normally be present if a rubber stopper was used and provide a better seal. Experiments showed that the bushing still tended to rise slightly, once the flask got hot, allowing vapor to escape. This was easily solved by applying a few wraps of black electricians tape, to the top of the flask and bushing, which completely solved the problem. The first picture of the apparatus in use is from early spring when temperatures where near freezing and with slow distillation air cooling was adequate. The second picture is from a hot day this summer and the receiving flask was placed in an ice bath. I have ideas for how one of those little $10-12 centrifugal table top fountain pumps could be used to pump the water, or iced water up, over the round bottom flask receiver if extra condensing power was needed.

A steel file may be needed to score the tubing if it needs to be made shorter. A propane torch is needed to heat the tubing so that it can be bent and then annealed.



BTW, I do have a ground glass distillation apparatus, but just for fun and skill development I wanted to build this one.

I probably should have another stopper, a two hole, in the round bottom receiving flask. A smaller diameter piece of glass tubing could extent out of it increasing the cold surface area and acting as an air cooled reflux condenser. This would help reduce the amount of escaping nitric acid vapor as well as probably reduce the amount of absorption of moisture by the nitric acid.


[Edited on 30-6-2014 by Hennig Brand]


The rest of the discussion was continued in this thread.


[Edited on 18-12-2014 by Hennig Brand]