the separation of a mixture of pervaporationsverfahren organic liquid compounds by asymmetric membrane made of an aromatic polyimid.

摘要

A pervaporation method of separating a liquid organic compound mixture at a high speed and efficiency through an aromatic polyimide asymmetric separating membrane produced from an aromatic tetracarboxylic acid component comprising at least 70 molar% of biphenyl or diphenylether tetracarboxylic dianhydride and an aromatic diamine component comprising 85 molar% or more of an aromatic diamine having 2 to 3 benzene ring structure, or 15 molar% or more of 9,10-di(aminophenyl)anthracene, di(aminophenoxy)diphenylsulfone, di(aminophenoxy)biphenyl or di(aminophenoxy)diphenylalkane compounds, or a mixture of 15 to 50 molar% of an aromatic diamine having a one benzene or pyridine ring structure and 50 to 85 molar% of an aromatic diamine having a 2 to 3 benzene ring structure.