METHOD FOR THE CONTINUOUS PURIFICATION BY DISTILLATION OF 1,2-PROPYLENE GLYCOL THAT ACCUMULATES DURING THE SYNTHESIS OF PROPYLENE OXIDE WITHOUT COUPLING PRODUCTS.

摘要

The invention relates to a continuous method of purification by distillation of 1,2-propylene glycol that accumulates as a by-product during the synthesis of propylene oxide. Said method is characterised in that the mixture that is produced during said synthesis, which contains the 1,2-propylene glycol, is separated in a dividing wall column into a low-boiler, medium-boiler and high-boiler fraction and that 1,2-propylene glycol is drawn off laterally from the column as a medium boiler.