Technique #1 - testing it outYou have to distill the vinegar to get sufficiently purified acetic acid (or purchase vinegar spirits)... otherwise you'll get the crap that the bacteria and yeast cells left behind in the fermentation process used to make vinegar (leaves black/brown crap on your flasks--perfectly safe to eat / drink, but not something you want in your sodium acetate). Slowly add baking soda (it bubbles) with a slight excess of acetic acid, then boil that down to get anhydrous sodium acetate.
The problem is then figuring out how to get back the acetic acid. I tried adding 1.25 eq of sulfuric acid, but it's not enough to even cover the sodium acetate. The reaction between sodium acetate and sulfuric acid is highly exothermic (careful!). It wasn't until 3 eq of sulfuric acid did it look possible to do.
Technique #2 - testing it outConcentration by azeotropically removing the water with tetrachloroethylene was a failure for me. The setup I used is:
From the bottom to the top:
1) flask with 30ml perc, 150ml acetic acid & stir bar
2) vigreux column
3) claisen adapter (monitoring temperature in the center hole)
4) pressure-equalized addition funnel
5) reflux condenser
The perc and acetic acid formed two layers. Then I distilled it (the vapors were at 90C until the water was removed...) until all of the water was left in the pressure equalized addition funnel (draining out the perc on the bottom layer in the addition funnel occassionally so it could recycle). Eventually one layer was left in the flask. Unfortunately, the perc and acetic acid were miscible! Now I've got perc with acetic acid instead of water with acetic acid. Great, absolutely fucking useless...
I must be missing something. I wish I was better at researching.