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neutrino
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Any residual sodium bicarbonate would have become the slightly basic sodium carbonate. I still don't see where the impurities would come from. Such a
weak base would have a hard time attacking steel.
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learner
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Yes that would explain it being basic quite well, adding a bit more vinegar(fizzing) got it back to neutral. The stainless steel pot doesn't look like
it has reacted in anyway. The vinegar I started with(8litres) was distilled and very clear with that crystal clear sparkle that good clean vinegar
has, it got yellower as the water boiled off and now down to 2litres has the colour of yellow printer ink in a bottle but still has that sparkle that
white vinegar has and looks clean despite being yellow . I also might note that this is my second attempt, the first time I used Cleaning vinegar
which is just high acetic acid content vinegar and had similar allthough darker results, but put it down to possibly the fact that I boiled it off
outside on a grill over a wood fire and thought that smoke might have adulterated it. This second time Standard distilled vinegar and boiled off
inside on the gas stovetop, but similar results allthough lighter. The stainless steel pot is in common for both times. I had read to do it in a glass
or iron pot but having nothing that size just went with the stainless steel pot I allready had. I'll finish evapotating it tomorrow and post the
colour of the crystals I end up with.
[Edited on 23-3-2006 by learner]
[Edited on 23-3-2006 by learner]
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evil_lurker
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Its probably the heat at the bottom of the pot causing slight thermal decomposition.
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unionised
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Loss of residual CO2 perhaps?
Since vinegar is made from fermented stuff it's quite possible that some sugars etc get carried over in the distilled product. These would caramelise
when boiled in weak base.
"Just because an azeotrope isn't listed in a particular edition of CRC or Perry's Handbook doesn't mean it can't exist in our universe". True, but
that fact that someone distilled the acid to better than the reported azeotrope does and, unless I missed the point that's what this means.
"Couple months ago , I prepared about 2.3 kg of acetic acid containing about 1-2 percent water. You can distill out water over a glass helices column
(1 inch wide * 6 feet tall) then distill out acetic acid. The temperature change is drastic from 100 to 115 degC when the water is gone"
(The azeotrope seems only to be listed in the older versions- I think it was a mistake and has been remove from later versions of the CRC book.)
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Magpie
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Whether or not there is an azeotrope was also hashed out in the 5 page thread "acetic acid/sodium hydroxide."
Here is one of my posts from that thread that may be of use:
"Vinegar at 5wt% acetic acid is 1.6 mole% in acid. According to the vapor-liquid equilibrium data I found at the library the liquid and vapor
composition at this liquid concentration are very nearly equal. This I believe makes concentration of the acid by distillation impossible or at least
impractical.
I also checked "Azeotropic Data" by Gmehling et al (1994). There were 52 citations! Pressures ranged from 1.07 kPa to 5864.7 kPa with 31 citations at
101.7 kPa (atmospheric pressure). All of the references indicated "none" for existence of an azeotrope.
Needless to say I'm giving up on distillation of vinegar. "
I did made some 65% acetic acid (from vinegar) via calcium acetate distillation with hydrochloric acid.
The single most important condition for a successful synthesis is good mixing - Nicodem
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jack44556677
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@ OP
I couldn't find his books / words, but I think I've found the process.
https://www.sciencemadness.org/talk/viewthread.php?tid=10545
https://books.google.com/books?id=d8lCAAAAYAAJ&pg=PA372&...
Basically, the chemical process of adsorption was discovered by Lowitz and he went charcoal mad as a result, I would too. He found that some of the
acetic acid is being absorbed into the charcoal (adsorption) where it can become much more concentrated than it can easily become in/with water. By
continually dripping / soaking and swirling the vinegar over the charcoal powder (with or without distillation / heating from below causing ultimately
plain water to distill over) you end up with concentrated acetic acid in the charcoal that you can extract out again with another solvent. According
to the sciencemaddness link above, the concentration can go as high as maybe 30% with no distillation/heat and maybe more like 40% with distillation.
Those numbers seem to be contradicted by the book I linked to above, which suggests that by alternating between freezing the high percentage vinegar
and seperating the solids, then continuing to distill with more charcoal powder that GAA can indeed be obtained.
The way he (and others from the time) describe it, it sounds as if there may actually be small GAA crystals inside / with the charcoal powder..... My
understanding is that if you could just get a few seed crystals, just slowly dripping regular vinegar over it will slowly build the crystal bigger.
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zed
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I was impressed by an older post. 2006..Garage Chemist:
-------------------------------------------------------------------------------------------------------------
In Germany, pharmacies only carry pre- made stuff too.
If you want a chemical, they will always have to order it for you.
The catch is that pharmacies can order it (since they are authorised to do so) and are also authorised to sell chhemicals to the public if they have
no reason for being suspicious of illegal use of the chemical. The worst they can do is to decline the request.
If you are old enough and don't order stupid shit like e.g. KNO3 (no pharmacy is going to sell you that! They know exactly that most people who want
chemicals are trying to make illegal fireworks) chances are good that you will get what you want.
It is advantageous to tell the pharmacy from which supplier they should order, because it can get very expensive otherwise (they don't search for the
cheapest supplier).
-------------------------------------------------------------------------------------------------------
It's a big world, and regulations are wildly inconsistent.
In the U.S., ordering KNO3 in order to make fireworks, or whatever.... Would probably be considered innocuous.
Well, I checked. Pyrotechnics suppliers limit you to 1lb per year w/o a license. Other folks may be less restrictive.
GAA we can buy without restriction, but it isn't cheap.
[Edited on 2-2-2019 by zed]
[Edited on 2-2-2019 by zed]
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Quieraña
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I am really curious about the charcoal filtration method. To me it sounds as if some form of crystal or adduct is created and I wonder if you even
have to powder the charcoal. Maybe like aquarium charcoal those little rocks would be could be even better because there would be more little pockets
I don't know you know but I wonder if the amount of time you let the vinegar sit and gets soaked up in the charcoal makes a difference or not though
I'm leaning towards the former. Also has anybody followed almost the instructions in the name of it glacial acetic acid I would wonder if you just
froze the vinegar and collected the liquid? Again all I have are my thoughts on this no application at this time but physical practice towards actual
production of OTC to not-so-OTC chemicals is in the mail so to speak, as in I feel the need to get back into the practice as the temperature outside
is starting to fall being almost September and since I do all my chemistry outside. Great stuff guys you have contributed to not just more knowledge
education but more curiosity and that in and of itself the curiosity is a gift because it ensures a purpose for living besides just existing day to
day. Yeah without chemistry without science in general I am so bored.. until I am actively practicing chemistry I am vicariously doing the experiments
right next to you in spirit so thank you for your descriptions your pictures your humor and even some of the rough criticism I've seen though rarely.
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Quieraña
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Hello again and Merry Christmas to those of you who celebrate Christmas and Happy Holidays all others. Anyways looking at these posts above, somebody
had mentioned an industrial process of oxidizing essentially a fermentation tank to make ethyl alcohol in h2o with constantly stirred water and
aeration and time. This makes me wonder: could I simply take denatured alcohol (95% etoh, ~5% meoh and <1% denatonium) and perhaps strong hydrogen
peroxide ( since I'm at this time limited only to over-the-counter chemicals AZ I'm in a credit bind and some Catalyst, be it as a base or acid, even
say copper seems actually likely perhaps passing ethyl alcohol through a copper tube really the whole purpose once you get to acetaldehyde you've got
acetic acid coming right around the corner if you let it sit out in the open, or in that aquarium tank which is what I'm visualizing anyways with
constant and continuous aeration until you cannot but smell glacial acetic acid emanating from said tank. And as far as I understand it is not
possible to dehydrate acetic acid to the anhydride by way of Oleum, absolute sulfuric acid, and acetic acid in its highest Purity as the acid. If it's
not about the experimentation but simply acquiring the chemical GAA and all you have like myself is OTC chemicals then this is exactly what I would
do: I would take any kind of vinegar it wouldn't matter if it's balsamic or white distilled although distilled white vinegar is what I would prefer
given it's absolutely clear and lime or slaked lime added to it drying the salt that forms calcium acetate simply taking this salt and add sulfuric
acid to it in the form drain cleaner from Lowe's (the high-test one that's pink not black as that stuff is gross although you could probably use the
black one even though it looks terrible) and then simply distilling that. I don't have a distillation setup so it's simply not a likely possibility at
this time. When I finally have proper lab equipment including quartz glass test tubes (hmm, makes me wonder if there sapphire glassware) and a
wonderful distillation setup with multiple distillation columns Etc, I'm going to go ahead and make myself a ketene lamp and go from there now that is
one of the easiest ways and then there is the methyl acetate method I can't remember that one I think it's methyl acetate and sulfuric acid distilled
but I'm not 100% sure on that I read it in a book in prison and write it in a journal in a pile of papers somewhere I'll dig through the paper and
find it I quote it directly from the book it was a classroom textbook on chemistry and it was in the back just before the appendix started. No I'm not
a hundred percent sure that that's exactly what was described but methyl acetate or it wasn't ethyl formate I think it really was methyl acetate
shouldn't wonder if it's ethyl acetate I'm missing something I don't know shouldn't that work ethyl acetate and sulfuric acid? And as acetate is a
common replacement for acetone especially in countries that fear acetone. Now I just made that up in theory so I don't know if it works but I cannot
see in my mind why not.
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annaandherdad
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Quote: Originally posted by jack-sparrow  |
By the way, "natural" is a very confusing word because people tends to forget that there are no differences between natural and artificial chemicals
when isolated in a pure form. Fermentation produced ethanol or synthetic ethanol is the same molecule. If it is pure, there are no possible
distinctions. Same thing for vanilla, vitamin C or sodium bicarbonate. |
Saw this old comment by jack-sparrow and had to add something. I know someone here (Rich Muller) who entertains audiences by telling them that it is
illegal in the US to sell wine that is not radioactive. This of course alarms certain people.
Eventually at the end of his talk it emerges that the authorities distinguish industrial alcohol from that produced by fermentation by the fact that
the latter contains carbon 14, while industrial alcohol, whose source of carbon is typically petroleum, does not.
Apparently the law originates from lobbyists for the wine industry.
Merry Christmas to everyone.
Any other SF Bay chemists?
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wakatutu
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Oxidizing ethanol seems to be the easiest way. I've tried neutralizing vinegar with sodium hydroxide, evaporating all the water out, loading it into
a RBF, adding enough sulfuric acid to neutralize the sodium ions, and vacuum distilling the whole mess. I obtained very little acetic acid, and it
wasn't as pure as glacial acetic acid, it had some water in it. And the distillation was very bumpy. It seems much easier to purify ethanol from a
natural or hardware store source, then simply oxidize it to ethanal and then to ethanoic acid.
[Edited on 25-12-2019 by wakatutu]
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S.C. Wack
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| Quote: Originally posted by learner | | Trying to Find Info On Johann Tobias Lowitz's 1789 method of concentrating Dilute acetic acid by repeatedly passing over charcoal. I can find very
little info other than that he obtained GAA in this manner. |
Löwitz is mentioned on the first page of the excellent 1885 book Acetic acid and vinegar, ammonia, and alum (John Gardner) from google or
archive.org, but not his process, so it must not be that great. So it sounds like it's just chromatography and charcoal is the adsorbent.
Calcium chloride in a desiccator apparently removes water but not acetic acid.
So, bisulfate isn't formed? It is said that vinegar distilled with bisulfate yields a more concentrated vinegar, beyond what one would expect from
getting the undistillable crap out.
Er well USA definition. As leu might say, your mileage may vary.
| Quote: Originally posted by learner | | It started of quite clear but as it is getting less and less it is getting darker and darker and I can't imagine it leaving white crystals of sodium
acetate. |
This is why one separates it from undistillable crap first.
It's the salt of a strong base and weak acid.
I suggest concentrating their battery acid.
People are entertained by bullshit far more than by facts.
I wonder if more corn ethanol is used to make ethylene than the other way around, because very little ethylene is converted. 2018 had some 16 billion
gallons ethanol (including 2-5% gasoline or pentanes denaturant) produced from 5.5 billion bushels of corn.
| Quote: Originally posted by wakatutu | | I've tried neutralizing vinegar with sodium hydroxide, evaporating all the water out, loading it into a RBF, adding enough sulfuric acid to neutralize
the sodium ions, and vacuum distilling the whole mess. I obtained very little acetic acid, and it wasn't as pure as glacial acetic acid, it had some
water in it. And the distillation was very bumpy. |
Maybe you did everything wrong! The right way should go smoother.
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Quieraña
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The method using the ester (I think from apples) methyl acetate? This one was relatively simple once the ester is acquired.. I want to know how to
make methyl acetate. Yet ethyl acetate like I said earlier is much easier to acquire and it's not sulfuric acid you add to it it's carbon monoxide so
either using formic acid and some reductant I can't think of or burning charcoal like in a smoker and running that smoke into a tube and bubble that
through the methyl acetate or perhaps even ethyl acetate. Please note that I have never done this and I'm not sure and so these are nothing but
speculations and so for that I do apologize I don't like to waste people's time
[Edited on 25-12-2019 by Quieraña]
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