abstract |
Ethylene glycol cannot be easily separated from 1,2-butanediol or 1,3-butanediol by atmospheric or reduced pressure distillation because of the closeness of their boiling points. Ethylene glycol can be readily separated from the butanediols by azeotropic distillation. Typical effective agents are ethyl benzene, 3-heptanone or diisobutyl ketone. |