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S.C. Wack
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I entered the single word "lye" in Google and got 493,000 results. The relevant results were very much in favor of "lye" meaning
KOH solution, not NaOH, most especially that made the old-fashioned way, by lixivating wood ash, which contains at least 10 times more K than Na,
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So lye gets a lot of hits. So?
Lye sodium gives twice as many hits as lye potassium. This should tell you something right there.
What relevant hits are those? You cant be talking about the links that you provided. Nowhere do they say that lye is only KOH, and excludes everything
else.
Yeah, that brainydictionary is very authoritative. Grasping at straws.
Try reading the old books. Nowhere do they say lye, they say potash lye or soda lye. They say caustic potash and caustic soda when talking about the
hydroxides.
If the modern definition of lye has been skewed, it has skewed in favor of NaOH, for whatever reason. Yet this does not mean that NaOH means lye
either, although no one is mistaken about what the Red Devil product contains.
You seem to have grasped that the word originally meant the leachate of ashes, in other words ---- potassium carbonate and other stuff, depending on
the ashes. Not the hydroxide.
They way you crudely try to twist things in your last post is even more laughable than most of your posts, and as usual it has little to do with the
subject at hand.
EDIT:
| Quote: | Originally posted by JohnWW
SC Wack, you are just a troll! You have given yourself away, by your utter irrationality. |
| Quote: | Originally posted by JohnWW
"Lye" is the term commonly applied to solution of potassium hydroxide, KOH, rather than NaOH. |
to which i said: bull, now and always.
to which JohnWW says: UTFG
to which I said: lye "potassium hydroxide" -"sodium hydroxide" = 2440 hits
lye "sodium hydroxide" -"potassium hydroxide"= 17,700 hits. Yes, it is obvious that the Google hits are very much in favor of
KOH, not NaOH. To JohnWW at least.
he refuses to accept what it says
which is, KOH is not and never has been the definition of lye. It has been included in the wide spectrum of lye, and so has NaOH, and NaOH is very
commonly called lye. I'm the one being irrational? I'm the troll?
[Edited on 12-2-2005 by S.C. Wack]
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JohnWW
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SC Wack, you are just a troll! You have given yourself away, by your utter irrationality.
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frogfot
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Oki, the first H2SO4/calcium acetate/ethyl acetate experiment failed. Neutrino, you were right about filtering.. it was a real pain to filter CaSO4
with vacuum.. and on drying the solids was nothing like CaSO4, it was composed of soft crystalline mass. So, I guess reaction is long from compleate..
and I've abandoned the filtrate. I have also recovered zero solvent.. all was adsorbed on CaSO4 (it separated on addition into water)
Now some happy news. Got another idea that I recently tested, and it seems to work. This time I wanned to use sulfuric acid with an acetate that will
form a soluble salt in alcohol. Reaction was performed in cold to prevent esterification.
I took 9,42 g sodium acetate (partially crystalline, so it should have some crystall water..), added it to 30 ml 92% ethanol and while cooling the
slurry in ice bath, I added 3,1 ml 96% H2SO4 dropwise, while stirring.
On checking of pH in solution, it remained around 5 at all times, which means reaction is fast. This is basically because Na2SO4 is slightly soluble
in alcohol, so it doesn't build up a coating around acetate salt.
Then I made attempt to filter the slurry, but this took alot of time. So, I transfered all mess into a beaker, heated and cooled it slowly hoping that
the small Na2SO4 crystalls will recrystalize to bigger. After, filtration went a bit faster but it was still slow..
After washing solids with ethanol, I distilled off fractions of 79-95*C and 95-124*C (5,73 g). There remained couple milliliters of brownish liquid.
There was no indication of ethyl acetate formation.
Then I titrated all products:
Fraction 79-95*C contained 1,1g AA
Fraction 95-124*C contained 2,68 g AA
Na2SO4(dissolved in water) contained 0,21 g AA
Theoretically I could get maximum 6,896 g AA, so I got 39% yield in form of 5,73 g 47% AA.
At first this seems to be crap, but, there are many buts...
First, this was a very small batch. Second, my ethanol (92%) and sodium acetate contained quite alot of water. This could be done better if I used
more concentrated denaturated alcohol and predried the acetate. Third, quite alot of AA destilled with alcohol. Though this shouldn't be problem
since it can be reused in next batch (ethanol doesn't even have to be dried).
One serious problem is the size of Na2SO4 crystalls.. How would one make them bigger? The only idea I can come up with, is to let it sit for days..
maby they will regrow.. or?
Bigger crystalls would simplify the filtering and most probably decrease the adsorbtion of AA on crystalls surface.
Time to make more sodium acetate..
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Magpie
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Have you tried laying down a 2-3mm bed of diatomaceous earth (kieselguhr) on your filter paper using a water slurry prior to filtering your Na2SO4
slurry?
[Edited on 12-2-2005 by Magpie]
The single most important condition for a successful synthesis is good mixing - Nicodem
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frogfot
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Nope, I couldn't actually find it in my previous attempts. Would usual clay do the trick?
But then again, Na2SO4 particles would still adsorb alot of AA...
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Magpie
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My guess is that clay would definitely not work. Sand would be much better. The reason diatomaceous earth is so good is that it's made of of
silaceous intricate skeltons of very small sea creatures (diatoms). This provides a very open structure for filtering. I visited my friendly
swimming pool supplier. He happened to have an open 50 lb bag of Celite. He gave me a coffee can full for nothing as I was buying some other
chemicals. 
The single most important condition for a successful synthesis is good mixing - Nicodem
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FrankRizzo
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SEM image of Diatoms:
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Quince
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| Quote: | Originally posted by frogfot
Now some happy news. Got another idea that I recently tested, and it seems to work. This time I wanned to use sulfuric acid with an acetate that will
form a soluble salt in alcohol. Reaction was performed in cold to prevent esterification. |
I tried this, making the sodium acetate from vinegar and baking soda, and using isopropanol instead of ethanol (I have none of the latter). It
didn't work, with the distillate (all of which came over at 79*C) having no acidity at all, and the brown shit left in the flask smelling worse
than the inside of the devil's asshole.
I need it to make lead acetate, as I don't have any calcium sources to make calcium acetate->copper acetate->lead acetate as discussed in
another thread.
[Edited on 12-6-2005 by Quince]
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The_Davster
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Glacial(?) acetic acid distillation
A pile of sodium acetate produced by boiling down baking soda and vinegar was heated over an alcohol burner untill it was dry. It had to be stirred
often or it would carbonize.
Based on a procedure from an old chem lab manual from the uni library, 20g of the now anhydrous sodium acetate was added to a 250mL RBF. 12-13ml of
98%H2SO4 was measured out separatly. A 19/22 distillation setup was assembled and the H2SO4 was poured ontop of the sodium acetate. The rxn was
exothermic from the start and white fumes were given off and some of the sodium acetate darkened. The mix was distilled over an alcohol burner.
White fumes were given off the entire time the distillate came over(pic 1 and 2 in attachment). I have no idea what these fumes are, they seem to
either dissipate or condense in the recieving beaker. The material left in the distilling flask was crushed with a stirring rod and washed out as I
did not want it so solidify completly in the distilling flask and be never able to remove it. It seemed rather carbonized. Yield of suposedly
glacial acetic acid was 8.1mL.
[Edited on 12-11-2005 by rogue chemist]
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Magpie
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Rogue I tried a very similar procedure only used vinegar and hydrated lime [Ca(OH)2] to form calcium acetate. I dried this in my drying oven. Then
reacted it with HCl. I thought about using H2SO4 as the formation of insoluble CaSO4 should drive the reaction. But I chickened out as I thought I
might have to scrape this out of my RBF. I then set up a fractional distillation column to get glacial acetic acid. I got some strong acid (60%
IIRC) but not glacial. I concluded that I did not have fine enough control on the temperature gradient on my distillation column. So I want to try
this again when I can insulate and control the column better.
Your situation seems strange to me with those white vapors and carbonized gunk. I wondering if the H2SO4 is being too agressive here.
The single most important condition for a successful synthesis is good mixing - Nicodem
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The_Davster
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Well, I do not really expect it to be glacial as the procedure called for changing the recieving flask when the temp reached 116C, but my thermometer
ends at 115(I need a better one)
I hope those fumes are just uncondensed acetic acid (thats what they smelled like with some weird smell mixed in) as a fair ammount of these were
released into my lab. I don't know about the H2SO4 being too agressive as the procedure can have 7.5% oleum used instead of the conc. sulfuric
acid. Perhaps it is even normal, but as it is a lab guide it wants students to find this out for themselves.
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mrjeffy321
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When distilling the Sodium Acetate and Sulfuric acid mixture to make Acedic acid, do you keep going all the way to dryness or just short of dryness?
How do you measure then final concentration of the condensed acedic acid solution?
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Magpie
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When using a fractionating column the temperature at the still head should be the normal boiling point of acetic acid. When it changes to 100C
you're getting water.
Titrate your acid or perhaps measure its density & use a table to find concentration.
The single most important condition for a successful synthesis is good mixing - Nicodem
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mrjeffy321
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what about this, skip the distilation process and then cool the solution to crystalize some of the Sodium ___ out.
Say with this reaction using Sodium Acetate and 10 Molar Hydrochloric acid.
NaC2H3O2 + HCl --> HC2H3O3 + NaCl
so say you start out with 1 mole of Sodium Acetate (82.04 g) and add 100 mL of 10 Molar HCl to react it completely to form Acedic acid and Sodium
Chlorde.
You will be left with a solution of Acedic acid and NaCl dissolved in about 100 mL.
This makes for a rather salty 27% acedic acid solution, and actually, with NaCl solubilty at about 36 grams / 100 mL of water, not all of the NaCl
will dissolve. You can remove some more of the NaCl by cooling it, further raising the concentration of the acedic acid.
Given it isnt pure and it isnt anywhere near the concentration some people are aiming at, but it saves the distillation step.
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neutrino
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>When using a fractionating column the temperature at the still head should be the normal boiling point of acetic acid. When it changes to 100C
you're getting water.
It would be the other way around. Acetic acid has a normal boiling point of 118*C, so it would come over last.
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Magpie
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Of course you are right. I just couldn't remember which had the lower boiling point.
The single most important condition for a successful synthesis is good mixing - Nicodem
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jimmyboy
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well its pretty clear that using sulphuric acid on an acetate just results in a black carbon mess -- the two i would like to try sometime would be
oxidation of ethanol (some everclear would work) or dry distillation of copper acetate -- the first one seems the most promising - mixing some alcohol
with excess permanganate and adding it to sulfuric would work - i was wondering if manganese dioxide would work just as well - much cheaper but not
nearly as potent - just add more? -- anyone tried these methods?
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ordenblitz
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I have distilled glacial acetic acid many times from the reaction of sodium acetate and sulfuric acid. It is quite easy infact. I can not figure why
you are having such problems.
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12AX7
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NaCH3COO + H2SO4 == NaHSO4 + CH3COOH, or is it more like
2NaCH3COO.3H2O + H2SO4(aq?) == Na2SO4 + CH3COOH ?
Tim
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Fleaker
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My friend tried the ethanol to ethanoic acid reaction with a strong oxidizer and 1 drop of sulfuric acid. He did not get any appreciable vinegar
smell, rather the smell was quite fruity, almost like the smell of fresh apples (I too smelled it). That was using potassium permanganate and heating
it to 50*C and refluxing in a test tube. There was oxidation and reduction because the solution lost its purple color and a sludge of MnO2 was seen on
the bottom of the tube. Based on his results which I saw for myself, I do not think you can get ethanoic acid that way. You're welcome to try for
yourself jimmyboy.
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jimmyboy
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hmm - well i read all the posts in this thread and alot of people are coming up with black mess in their reactions - possibly unclean acetate from the
vinegar/sodium bicarb reaction i would guess - a "fruity smell" you say? hmm definitely acetaldehyde --- was their any special setup to your reaction
orden? you said you have done it a number of times -- or just dump the sulfuric in the acetate and distill..
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ordenblitz
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It's been a while since I have done it so I am working from memory.
They first time I did this I used exactly what you are using, NaHCO3 + Vinegar produced sodium acetate. I think mine had a slight excess of
bicarbonate but it didn't matter since I used an excess of H2SO4.
I remember that the reaction started very fast giving me little time to assemble the condenser to the flask. The next time... I pre-chilled the acid
before adding it to the flask. While this reaction proceeds similarly to making HNO3 from nitrates and sulfuric, the heat required is less so you
should proceed slowly and judiciously with the burner.
[Edited on 31-5-2006 by ordenblitz]
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Magpie
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I have reduced some 5% strength vinegar to 127g of damp sodium acetate. I then reacted this with 25mL of sulfuric acid (17.5M), cooling as required.
There was a lot of Na2SO4 being formed so added 27mL of H2O just so I could keep it stirred on my magnetic stirrer. Then I removed the Na2SO4
crystals by decantation/filtration. I now have about 125mL of solution that I estimate is 50%H2O/50% glacial acetic acid.
For ordenblitz: How do I get the GAA isolated now. By fractional distillation, or what? How exactly did you get the GAA?
The single most important condition for a successful synthesis is good mixing - Nicodem
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ordenblitz
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I took the extra time to not only boil off the excess water in the sodium acetate but also cook it down to absolute dryness with heat before making
the GAA. It was then a simple matter of adding the H2SO4 to the acetate in a boiling flask and distilling the product with a bit of additional heat.
I never made it the way you are proposing and I cant say if its easy to remove the water after. But I can tell you that removing the water from the
acetate is easy.
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Magpie
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Thank you , ordenblitz. I'm not a fan of trying to separate water from acetic acid. I will be giving your method a try. 
The single most important condition for a successful synthesis is good mixing - Nicodem
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