1,6-hexanediol purificn - from diol mixt by 3-step distn process

摘要

Diol mixt. produced by hydrogenating acid mixt. by product from cyclohexane air oxidn. and distilling off water and readily volatile alcohols, is subjected to a 3-step continuous vacuum distn. where it is freed from high-boiling constituents in a first column; distillate is introduced at 170-190 degrees C sump temp. into the bottom part of the second column which works with very low pressure drop; a pre-run is sepd. and pure 1,6-hexanediol is distilled off from sump-prod. in a third column. Prod. is obtd. in a 99.8% purity and 98% yield and is a useful raw material for elastomer fibre-forming polyesters and polyurethanes.