Patent ID: 7030254

Claim:
A process for producing purified propylene oxide comprising: first to sixth steps below, and using heat of reaction generated in the first and/or second steps as a heat source for rectification in the fifth step and/or a heat source for rectification in the sixth step: first step: a step of obtaining cumene hydroperoxide through oxidation of cumene at a temperature of from 50 to 200° C., second step: a step of obtaining propylene oxide and cumyl alcohol by reacting cumene hydroperoxide with propylene at a temperature of from 0 to 200° C. in the presence of an epoxidation catalyst, third step: a step of separating into a fraction (2) containing crude propylene oxide and a fraction (3) containing crude propylene by subjecting an outlet liquid (1) of the second step to rectification, fourth step: a step of obtaining a fraction (4) containing crude propylene oxide and a fraction (6) containing cumyl alcohol by subjecting the fraction (2) to rectification, fifth step: a step of obtaining a fraction (7) containing purified propylene oxide by subjecting the fraction (4) to rectification, and sixth step: a step of obtaining a fraction (5) containing purified propylene by subjecting the fraction (3) to rectification, wherein the reaction temperature in the first and/or second steps is higher by 10° C. or more than the temperature of a heat source for rectification in the fifth and/or sixth steps.