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MagicJigPipe
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In my experience a fume hood is not needed. Of course you should use some sort of ventilation, though. IMO, gentle heating isn't even needed either.
Real borosilicate (Pyrex brand) beakers are so tough. I have used the same one for boiling H2SO4 for YEARS (easily 20 gallons of 33-35%) using
everything from a wire "hotplate" (direct contact, like an electric stove that gets red) turned to full power to a propane flame. It is dirty but it
just keeps on ticking.
IMO, there is no need to make it last all day. I just boil that shit on high and it seems to give the same results as taking it slow. For some
reason the "fumes" have never bothered me. Not one bit. Maybe it's just because I'm semi-young, who knows... My lungs certainly aren't perfectly
healthy, though.
Like Pulverescent stated above, NEVER use an oil bath for something that boils at over 300*C unless it is ABSOLUTELY necessary.
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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Pulverulescent
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I'd still say pyrex cooking vessels should not be placed over a roaring flame.
Their sides and bottoms are very much thicker than those of ordinary RBFs and beakers.
Slow heating, at least in the initial stages, is always advisable, IMO.
P
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Aqua_Fortis_100%
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I have experimented cheap chinese iron enameled pan with some sucess.. I just make sure buying the stuff that have no flaws, cracks or other thing
that expose the iron f the pan..
I have boiled battery acid in this with a iron enameled lid (with comes with the pan) loosely stoppered until fumes evolved .. Unfortunately I did not
continued to raise the concentration since my backyard isn't that great and so the ventilation isn't too good.. But the amazing thing was that the
enamel , like all the pan, did not seem to change with and after the procedure.. My sulfuric was slight yellow since I was using charcoal for heating
and small flying ashes contaminated my H2SO4, even so I using the enameled iron lid..
IMHO seems to be much greater and probably safer than soda glass (yes.. many years ago I tried to do it in 1,25L coke glass bottle, glass beer bottles
and even glass bolw and all these procedures were quite dangerous. Some bottles cracked and spilled hot sulfuric everywhere on the ground..God was
good enough that anything occured to me..  ) or maybe even pyrex 
I have heard somewhere at this forum that conc. H2SO4 does not attack so well iron metal.. Does this make sense? If yes, then would be the enameled
iron pan even a better choice..
But as soon as I discovered a chem supplier that sell tech grade 98% real cheap I discontinued concentrating sulfuric from battery acid, although I
still like so much the idea of getting that stuff from auto stores (in old used batteries) FOR FREE.. Is actually my prefered source of dilute
sulfuric, even with no well know concentration.. So I rarely dilute my conc. acid..
BTW, unfortunatelly this damn cool drain cleaner often discussed at this board is not OTC here.. So the only real way for all of those living in any
part of the world is definately the battery electrolyte...
[Edited on 18-5-2008 by Aqua_Fortis_100%]
"The secret of freedom lies in educating people, whereas the secret of tyranny is in keeping them ignorant."
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ADP
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I did a vacuum distillation of HNO3 today, I am going to go buy a new propane tank and nozzle and attempt a H2SO4 distillation maybe next weekend.
I'm going to use liquid lightning which should suffice. I'll let the water come over first and then distill at the hottest temperature to get the
H2SO4 to come over. I'll post pics if I get the project underway... Any ideas?
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MagicJigPipe
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| Quote: |
I'd still say pyrex cooking vessels should not be placed over a roaring flame.
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I didn't say anything about a (fake) Pyrex cooking vessel. However, they WILL work up to about 550*F in an oven even if they cool off at room
temperature. Just apparently not with a direct source of heat.
Also, I still can't believe that the US seems to be the only country that has "pure" battery acid at it's auto-parts stores. I bought 5 gallons of
33.5% acid for less than $15 a few weeks ago. What about mechanics that refill batteries? How do they get it? I mean, that's what that 5 gallon
"bag" was designed for. Mechanic use.
[Edited on 5-18-2008 by MagicJigPipe]
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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Pulverulescent
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| Quote: | Originally posted by MagicJigPipe
| Quote: |
I'd still say pyrex cooking vessels should not be placed over a roaring flame.
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I didn't say anything about a (fake) Pyrex cooking vessel. |
Do you see that (word) in my post, MJP?
The boron additive in glass doesn't eliminate the COTE; it merely reduces it, and heavy-walled vessels, if they're heated too rapidly, can
crack from the induced thermal strain.
I once placed a hot pyrex cooking vessel on a wooden bench, only to have it shatter violently before my eyes.
I found that the sharp point of a nail which someone had driven into the bench from its underside had protruded a nano-metre above the surface of the
wood, and it was this that caused the vessel to shatter.
The vessel was very hot and the nail not so. . .
If the vessel had been at, say 200*C it would still have happened---just not quite so, um, energetically.
Thin-walled RBFs are another matter, and don't need such precautions.
P
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12AX7
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I regularly heat a moderately aged Pyrex bowl (must be at least 10-15 years old) over soft propane flame. Fine so far.
Tim
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MagicJigPipe
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I don't share your experiences with the fragility of borosilicate glassware. So far I have had no breakages due to thermal stress (or weak mechanical
stress) and I used to abuse the hell out of my glassware because I used to think it was basically impervious to anything except for being broken with
physical force. I still have all of my glassware from back then (except for the ones that were broken by the cops), too.
I understand that if it were heated fast enough it would break. But that's true with a lot of things. For me though, using normal lab techniques,
they don't seem to break easily at all. Even when using a direct propane flame at full power. Maybe I'm just lucky?
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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ADP
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Liquid Lightning
I don't know what the HELL consists of the "12 buffers" added to the "Virgin sulfuric acid" in liquid lightning but they sure know how to fuck it up.
I attempted a vacuum distillation of the stuff today - I wanted to get the water out first and then distill over the H2SO4 to bypass the carbon etc.
buffers they add in there.
Anyway at about 140dC the stuff started to boil, I'm not sure if the vacuum was on or not but anyway the whole solution started to foam up like soap
detergent making it impossible to continue heating without the bubbles shooting up the condenser column.
This picture accurately describes my situation...
It worked fine for nitric acid synthesis/distillation... perhaps the nitric oxidized the carbon etc. buffers... I'm curious if I added a small amount
of conc. H2O2 to clear up the buffers and then distilled what would happen. Maybe I'll try that this week. Any suggestions?
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MagicJigPipe
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DO NOT use Liquid Lightning. It is quite possible that it's the worst acid for this purpose. The "virgin" and "12 buffers" comment should have clued
you in. If it foams, well, don't buy it again! I assume you got it from Home Depot because that's the only place I've seen it. Another thing that
told me to steer clear of it is that it didn't have a plastic bag wrapped around it.
Even if you don't have an Ace Hardware in your area, just about any other brand of H2SO4 drain cleaner will work better. That is the blackest drain
cleaner I have EVER seen! Yuk!
Also, you shouldn't use cold water to distill H2SO4. There's a post that Sauron made around here somewhere that explains why and also what
temperature your coolant water should be for certain distillate temperatures. I think the general rule was to keep it around 20 degrees below the
boiling point of the pot liquid.
Also, where did you buy your West condenser and what brand is it? I have one that looks the exact same (except I broke mine  ). (I know they all look basically the same but this one is EXACTLY the same).
Before I stop, here's an anectdote about how sellers on eBay lie their asses off just to make money. One was selling a 200mm Ailhin condenser that
was stained so redish (hard water, I assume) you could barely see through it. They claimed that it had "hardly been used" and was "like new". They
also had a reserve on it and had started the bidding at $40!! It angered me greatly...
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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Formatik
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How about adding anti-foaming agents?
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Pulverulescent
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| Quote: | Originally posted by MagicJigPipe
One was selling a 200mm Ailhin condenser that was stained so redish (hard water, I assume) you could barely see through it. |
I saw a red-cored condenser recently, too---eBay or UGT; it was very red---scarlet/crimson, and I assumed the glassblower was into red glass
and had inserted it into the condenser purely for effect.
I thought it looked really good---so good---I wanted it kinda' badly.
The one you saw may have just had rust in it; my sole condenser has so much rust (reddish-brown) I was afraid it'd interfere with heat transference
during distillation.
P
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ADP
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| Quote: | Originally posted by MagicJigPipe
Another thing that told me to steer clear of it is that it didn't have a plastic bag wrapped around it.
Also, where did you buy your West condenser and what brand is it? I have one that looks the exact same (except I broke mine ). (I know they all look basically the same but this one is EXACTLY the same).
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They started putting plastic bags on them but yes Liquid Lightning is pretty bad stuff. The only problem is that it's the only thing I can really get
around here that I KNOW of... I'd love to get a hold of some rooto but that might require a little trip to the next town over. I'll keep it in mind
though.
As for my West condenser, it's Ace glass and I actually got it for free. My high school was cleaning out the lab when I went there and it was covered
in dust on a top shelf somewhere so I asked to have it... I DO need to run some H2SO4 through the outer case to remove the hard water stain but just
haven't yet as it doesn't really affect anything.
Anyway as far as liquid lightning is concerned I think that it is fine for synthesis of say HNO3 and then distilling but I'm going to have to find a
better brand if I want to use it alone as H2SO4.
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MagicJigPipe
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Yeah, mine is Ace, as well. That's why I almost cried when I broke it (not really, but, you know). Are you in the US? Try looking your some smaller
"Mom and Pop" stores. That's the only place it is available here except for Ace Hardware (and there's only Ace Hardware, all of the other ones have
closed down since the late 90s apparently).
"There must be no barriers to freedom of inquiry ... There is no place for dogma in science. The scientist is free, and must be free to ask any
question, to doubt any assertion, to seek for any evidence, to correct any errors. ... We know that the only way to avoid error is to detect it and
that the only way to detect it is to be free to inquire. And we know that as long as men are free to ask what they must, free to say what they think,
free to think what they will, freedom can never be lost, and science can never regress." -J. Robert Oppenheimer
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ADP
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Yeah I had a graham condenser that broke once and made me feel the same way. Yeah I'm located in MS in the U.S. There's an Ace hardware in the town
over from me that I might visit today if I get time - if I do I might buy a few liters of rooto for the summer. Basically I have all summer to
experiment and what not so I'm making the most of it.
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ADP
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I couldn't find rooto at ace but purchased "liquid fire" instead which I know to be good sulfuric. The store was pretty small though so I'm going to
go to a bigger one in a week or two. More experiments to come hopefully.
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mr.pyro
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Liquid Fire is good stuff. That should work well for you. It has always worked well for me for nitrations and distilations.
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grndpndr
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Never had any problem with the Santeen brand SA drain cleaner from ace either though its the usual waste sulfuric acid drk brown black.I had assumed
it had been used to pickle steel during the manufacturing process and the majority of contaminants were iron oxide.Never the less 0 problems thus far
with nitrations.Although despite the cost I prefer buying virgin electrolyte from the local garage and reducing it per hotplate.I am fortuate though
in that we have a chemical supply that sells SA and 70%nitric and will deliver free of charge if your on thier truck route.makes for cheap 70% Nitric
w/o shippin /hazmat.
Total delivered 2.5l carboy some $36!
Can someone share a Mail order/ chain garden center AN source?CAN calcium AN 27-0-0 is satisfactory.
[Edited on 26-5-2008 by grndpndr]
[Edited on 26-5-2008 by grndpndr]
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Chemist514
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RFC : distillation of sulfuric acid
Hello all!
Just a request for comments regarding my latest attempt at this process..
After some thought we have decided to leave the drain opener acid sources in the original packages, we have not been able to locate a reputable
chemical source for pure sulfuric acid, even requests for battery acid from the usual places results in suspicion, seems this one is not a locally
available item.. we will purify only the acid from "various sources"... spent fisher bottles from the local university, discarded batteries etc, and
leave the rest for future considerations (pure is not needed to make some other acids etc..)
20 ml or so was placed in a 100ml 14/20 flask connected to a basic distillation setup (no water) and allowed to reach some 350 degrees. the flask was
allowed to dry on cooling, after the water had passed over and we waited for the acid to fume it was noticed that the acid was not condensing back, it
was leaving as vapor through the vent port on the receiver adapter..
Question : How long must this condenser be? I can chain 2 lieburg and then feed that into a graham but this seems like overkill, what is being used
commonly for this app? Looked like basic 14 inch west's in the pics..
This process was again done with a 250 ml flask and much less heat, 270 approx, seems like we have about half volume removed as water, need to test
ph.. acid! not strong but that was not expected!!
I really would like some pure, and we have it in 4-5 small bottles that need to be mixed for proper storage.
I wonder whats left in there after bromicacid's H2O2 cleanup?
Additional info.. I added about 10 ml of Clear-line drain opener which is available here.. at about 250 C the pink was gone... well, its not gone,
just.. its not pink now.
Update : The 250ml flask is room temp now, and clear as water.. nice that, we know theres scat in there but its alot better to look at!
Scanning over the various threads we find we should not be using a jacketed condenser, I have no tubing with a ground glass joint for this app so I'll
chain at least 2 of them or pick one and add the graham..
Sand needed to be roasted? and sifted for smallest grain size...
Erm, well its roasted now! lol. I just sifted it, but we didnt have heat transfer problems so this is just proper procedure I suppose..
And we will leave the hotplate settings fixed one level per hour.. must go slow to see where this window or water end and acid boiling starts..
Kudo's to UGT all 14/20 glassware purchased there and must be at least decent as it survived this... lol.
Wish I had some input but the musing helps muchly. thanks for your time.
New (Last?) Try :
Ok, lets use what we've learned so far...
I believe it was Woelen who saw a reference to using a vigreux as a high temp distillation device.. This is a nice idea!
Placed 200-250 ml of waste acid in a 500 ml flask and added an adapter, stopper in adaper, 14/20 to 24/40 adapter, vigreux metal keck to 24/40 down to
14/20 then a 14/20 "drip tip", maybe 6 inches that, will allow me to switch flasks better...
Used fine sand well dried in the sand bath and wrapped the first adapters in fiber insulation to stop water from dripping back.
Applied heat... I'm suffering from hold up with 14/20 here. need to keep setup microscale though.. maybe a 24/40 adapter should be obtained...
*sigh*
54 mins running and temp at 234 C I see vapor build up in the "condenser"...
[Edited on 21-8-2008 by Chemist514]
[Edited on 22-8-2008 by Chemist514]
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Chemist514
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Hmmnn... Cant seem to edit, odd.
now 2 hours 11 mins, temp 290 C less water now in hot end of the vigreux.
Must locate info on if system must be cooled and dried before passing over the sulfuric acid itself, temps should be way off, may be hazardous!
The Vigreux is much thinker glass... its not touchable now which is starting to concern me slightly..
This took some 9 hours!
Ok.. next day, all went well with the first batch!!! *DANCE!*
Second batch had some more questionable acid in it, some very strange green-yellow, oily liquid came over before even the water, I think it may be
whatever substance would form in boiling H2SO4 a partially dissolved stirring bar, a lot of lead sulfate, plus whatever else is in there that I do not
know about... I'll assume silence..
Temp being held for 2 hours at 290 - 300 , that should burn out whatever may be in there, then I'll start over with that batch in clean glass.
*ponder* alot of brown fumes were evolving, perhaps some nitrate was in there.. I think Sulfuric acid vapor is white from what Ive read here..
What color is teflon smoke? lol.
All the best to everyone, be safe!
[Edited on 23-8-2008 by Chemist514]
Chemistry : An instrument which sharpens and expands the powers of observation, which gives point to the perceptive faculties, and which develops and
elaborates the powers of thought and of reason. -- John Attfield, F.R.S.
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darel
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I use a 200mm graham condenser with a drip tip. My setup is simple and get at least 98% concentrate. I put all 32oz of Rooto brand in a 2 liter flask
and have an upside down U joint that connects to the condenser so it's parallel with the flask. The flask and elbow are covered in tin foil. The setup
is 24/40. The fisrt 100ml or so is water, then a dense milky white smoke shoots back and forth through the elbow and condenser. The smoke doesn't
condense but disipates into the air when it make it out. Sometimes a cloud of smoke stays in the apparatus during the run. I collect everything after
that plume of smoke in a seperate container because from there on out is damn clean H2SO4. There is a crystalin substance at the bottom of the flask
and when 50 ml remains in the flask I shut off the hot platead let everything sit and cool until I can touch it.
I have never tried a reflux setup. How tall is vigruex?
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darel
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I had great success this weekend with a product from lowes. It's called Greased Lightning Power. Less than $7 after tax. I didn't take measurements to
figure for the amount of water, but I would say in the neighborhood of 60-70% sulfuric acid. Setup was simple. 2 liter flask with a graham condenser.
All 24/40 joints and tin foil around the flask and first half of the elbow.
Boiled off the water first at low on the hot plate. Foam was coming off pretty good, but settled down after a few minutes. You know the water is gone
when there is no more bubbles and you have a hot, still brown liquid.
Once all the water was gone, I cranked up the heat to medium. You know you have acid when the last few drops of water came over and the collection
beacker warms meaning acid is present in the solution. I switched beackers and started collecting a thick, dense, slightly yellow liquid.
I actually boiled this stuff dry till the black residue was left and the bottom was pretty much dry. I took my hydrometer and the liquid weighed out
1.839 .
I have always used Rooto but I haven't been able to find it lately. The biggest differences with these drain cleaners was with Rooto, during the
distillation a thick milky white cloud would come off and the contents in the flask would clear. This stuff from lowes had a little white cloud at the
beggining of the acid coming over (another way of telling the water has boiled off) and the contents of the flask was the same color throughout the
distillation.
Both of these drain cleaners had the same shinny, glassy crystals leftover. Not sure what it is.
Overall great product. Just thought I'd share.
EDIT BY POLVERONE: 800 pixel width maximum for attached images!
[Edited on 10-6-2008 by Polverone]
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darel
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cleaning sulfuric acid
Anyone know what the crystal like solid on the bottom of the flask is after distilling Rooto?
 
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1281371269
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Some high boiling point impurity in the acid I would assume... Do you have any information on what was in the drain cleaner?
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hissingnoise
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It would have to be pretty inert to survive boiling H2SO4---could be SiO2, but why it's there is anyone's guess. . .
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