PURIFICATION OF DIHYDRIC PHENOLS-CONTAINING MIXED SOLUTION BY DISTILLATION

摘要

PROBLEM TO BE SOLVED: To provide a method for purifying a dihydric phenols-containing mixed solution by distillation, capable of preventing concentrated dihydric phenols from thermally deteriorating in a reboiler (heater) in the bottom of a distillation column and stably carrying out distillation operation in high yield for a long period. ;SOLUTION: In this method for purifying a mixed solution consisting mainly of a lower alcohol, dihydric phenols, a dihydric phenolalkyl ether, etc., by using distillation method in which plural distillation column equipped with flow-down film type reboilers are combined, a first distillation operation obtaining a low boiling point material as a first fraction from the top of a distillation column and pulling out a first bottom liquid from the bottom of the distillation column by feeding the mixed solution to the first distillation column and a second distillation operation obtaining dihydric phenol alkyl ether as a second fraction from the top of the distillation column and pulling out a second bottom liquid by feeding the first bottom liquid to a second distillation column are carried out. Thereby, heat deterioration of the dihydric phenols can be prevented in high level during distillation operation of the mixed solution in which thermally unstable duihydric phenols consumed by pyrolysis, degeneration, heat polymerization, etc., by being heated at high temperature are included and sufficiently purified dihydric phenol alkyl ether can industrially stably be obtained.;COPYRIGHT: (C)1999,JPO