Patent ID: 7285187
Filing Date: 2007-10-23
Classification: C07D

Abstract:
1. A process for purifying propylene oxide, which comprises: subjecting a liquid reaction mixture containing propylene oxide obtained by a reaction of cumene hydroperoxide with propylene, and water, hydrocarbons and oxygen-containing organic compounds as impurities to extractive distillation using a linear or branched saturated or unsaturated hydrocarbon having 7 to 20 carbon atoms as an extractant, with an extractive distillation column, recycling the extractant after separating propylene oxide and then purifying for separating the impurities, and controlling a concentration of propylene glycol contained in the extractant supplied into the extractive distillation column to 20% by weight or less, and wherein the liquid reaction mixture to be subjected to purification is one obtained by subjecting a reaction liquid obtained by reaction of cumene hydroperoxide with propylene after recovery of propylene to crude distillation to separate propylene oxide from cumene and cumyl alcohol.