METHOD FOR PURIFYING PROPYLENE OXIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for the stable purification of propylene oxide giving high-purity propylene oxide in high efficiency. SOLUTION: The method for the purification of propylene oxide contains the following steps. The 1st step to distillate the stock liquid in a distillation column and separate a column bottom fraction containing aldehydes having a boiling point higher than that of propylene oxide; the 2nd step to carry out the extractive distillation of the column top fraction of the 1st step by using a 7-10C hydrocarbon as an extractant and separate the fraction into a column top fraction containing water and almost all part of the aldehydes and a column bottom fraction containing propylene oxide and the extractant; the 3rd step to separate the column bottom fraction obtained by the 2nd step into a column top fraction containing propylene oxide and a column bottom fraction containing the extractant; and the 4th step to distillate the column top fraction of the 3rd step by a distillation column and separate the fraction into a column top faction containing aldehydes having boiling point lower than that of propylene oxide and a column bottom fraction composed of propylene oxide. COPYRIGHT: (C)2005,JPO&NCIPI