Concentrated solutions of acetic acid are often sold in chemical supply and photography supply stores. However sometimes it can be rather expensive, hard to get, or in inconvenient quantities. By far the most popular place to get acetic acid is from vinegar. Unfortunately it is only around 5% and has limited use. Vinegar however can be turned into glacial acetic acid with a little bit of work, and a few other readily available chemicals.

First thing you will want to do is neutralize the vinegar with baking soda or some other base such as carbonate or a hydroxide. This will produce a sodium acetate. Boil the water away until the sodium acetate is dry. Careful not to forget about it because the sodium acetate will burn, or begin pop all over when it begins to dehydrate.

Once you have dry sodium acetate you will want to react that with an acid. Generally acids stronger then acetic acid will work so this includes hydrochloric acid, phosphoric acid, sulfuric acid and sodium bisulfate. If you want a nearly pure and dry acetic acid you will have to start out with an acid that is also concentrated . I recommend using either sulfuric acid or sodium bisulfate. Sulfuric acid being the better of the two to use.

Adding one mole of sodium acetate to one moles of sulfuric acid will yield and sodium bisulfate and acetic acid upon distillation. Adding two moles of sodium acetate and one mole of sulfuric acid will yield sodium sulfate and acetic acid upon distillation. I have had the best yield of acetic acid using the mole to mole reaction.

CH3COONa + H2SO4 = NaHSO4 + CH3COOH 2CH3COONa + H2SO4 = Na2SO4 + 2 CH3COOH

(the bottom reaction is actually: 2CH3COONa + H2SO4 = NaHSO4 + CH3COONa + CH3COOH and then the NaHSO4 reacts with the remaining CH3COONa to form more CH3COOH)

Alternatively if you feel sulfuric acid has better uses, or if you don’t have any, you can mix dry sodium bisulfate and sodium acetate and heat it until acetic acid begins to come off. the vapors are of course collected by distillation. This is a lower yielding reaction, and also the last half of the 2:1 reaction mentioned above.

CH3COONa + NaHSO4 = Na2SO4 + CH3COOH

If you do not need glacial acetic acid, you can mix hydrochloric acid or a solution of sodium bisulfate with sodium acetate and distill until dry. The concentration of the first acid will determine the concentration of the acetic acid distilled. Acetic acid produced from hydrochloric acid may contaminated with hydrochloric acid if you added an excess of hydrochloric acid. In order to prevent this contamination have a slight excess of sodium acetate when you begin to distill.

CH3COONa + HCl = NaCl + CH3COO


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