[Harley]

I have a wash of 70% ethanol + ~30% water which I wanted to redistill to make clean vodka. I added sodium hydroxide to the wash to create an alkaline environment (pH > 12) to hydrolyse the ethyl acetate in it.

After adding it and heating up the wash, it turned a red/orange/brown colour. After cooling it and letting it settle, the wash returned to its original clear colour and I gathered quite a bit of brown precipitate from the bottom of the tank.

Anyone know what it might be?

It may be Iron hydroxide Fe(OH)3 which would form from a reaction between either [sodium hydroxide + Iron Nitrite] OR [sodium hydroxide + Iron(III)] but I have no idea how either could have got in there. The tank is made of 304 stainless steel.

Ideas?

[chenbeier]

We dont have a cristal ball. What was done with the alcohol before. Need probably an analysis what is in. Normal spiritus has additives, so its not drinkable. Also the separation by distillation is not possible because of azetrop.