Benzaldehyde distillation

[harry]

The other day swih aquired a ltr of benz for some L-PAC experimentation. While adding the benz a little trickle was left on the rim of the container which after returning an hour or so later it left a crystal mass. The fermentation didn't go that well, after adding the benz the gas evolution slows right down. For a 20 ltr ferment swih calculated one could add up to 150 ml, from what swih read here on the hive. But after about 50 ml(10ml every hour an a half) fermentation is non-existent. Now after givng the background of my prob I was wondering if some wise bee could tell me if 1; the impurities in the benz are causing the yeast die off and 2; if a normal distillation will purify my benz. By normal I mean usind no vac.

Harry.

[torture]

Hello Harry (and all other bees!)

I don't think that I have your answers, however i'm very interested in this route as on paper it seems like a _very_ viable path (in industry too I guess..) Some questions that popped into my head are:-

How long had your yeast been fermenting without any PhCHO? Did you have a maintained temperature? Is the fermenter being fed air? What impurities does your feed stock have as in homemade (path) / AR / LR? What strain of yeast? Any pH buffering / monitoring? Additional Pyruvate? Did the yeast drop (dead) or simply stop producing gas bubbles?

I guess someone that has these details might be better equipped to help with these answers too. IIRC the PhCHO is toxic to the yeast without a way to monitor the reaction speed (curves/slopes) or the optimal environment addition estimation could be tricky and killing the yeast?

Would love to hear about clandie success in a 20l brewing kit giving 10g/l in 2 days.

[bio]

You need to exclude O2 (air) to prevent the formation of benzoic acid ( your crystal mass). Maybe traces of this affected the fermentation. For better results with disilling PhCHO use low vacuum so it distills over about 110 Deg. This prevents most of the bumping which happens at higher vacuums. Stir like mad and no inlet tube. Seal the receiver immediately when finished.