A CONTINUOUSLY OPERATED DISTILLATIVE PURIFICATION OF 1,2-PROPYLENE GLYCOL FORMED IN THE COPRODUCT-FREE SYNTHESIS OF PROPYLENE OXIDE

摘要

A continuously operated process for the purification by distillation of the 1,2- propylene glycol formed as by-product in the synthesis of propylene oxide, wherein 1,2.propylene glycol is isolated directly from a wastewater stream obtained in the synthesis of propylene oxide and said wastewater stream containing the 1,2-propylene glycol is separated in a dividing wall colunm into low-, intermediate- and high.boiling fractions and the 1,2- propylene glycol is taken off as intermediate boiler at the side offiake of the column.