Ion Exchange Membranes for Pervaporation - A Patents Review

Pervaporation is a newly emerged separation process, known for its higher efficiency, lower energy consumption lower capital cost and so on. The main research field in pervaporation falls into three aspects: 1) the investigation of new membranes of good separation performance; 2) methods for manufacturing pervaporation membrane with high performance; 3) process modeling to find the bottleneck in the separation process. To date, lots of research papers are published and patents concerning the above mentioned research aspects have also been brought into the sight of those skilled in the art. As a branch membrane for pervaporation purpose, an ion exchange membrane, which is prepared from the charged polymers containing either anionic or cationic groups, has an important influence on the development of pervaporation. This paper thus discusses some valuable patents concerning the research of ion exchange membrane for pervaporation. Some basic processes using anionic membrane or cationic membrane, ways for the modification of charged polymers, manufacturing of pervaporation membrane and some insights of the mass transfer behavior are reviewed in this paper and finally a perspective conclusion is made.