US 11,926,707 B2
Preparation method of zeolite/polyimide composite membrane and applications thereof
Xiang Wang, Wuhan (CN); Danxia Chen, Wuhan (CN); Yanling Li, Wuhan (CN); Jun Wang, Wuhan (CN); Xiaoli Yang, Wuhan (CN); and Huajun Duan, Wuhan (CN)
Assigned to WUHAN UNIVERSITY OF TECHNOLOGY, Wuhan (CN)
Filed by Wuhan University of Technology, Wuhan (CN)
Filed on Nov. 26, 2020, as Appl. No. 17/105,545.
Claims priority of application No. 201911170360.5 (CN), filed on Nov. 26, 2019.
Prior Publication US 2021/0155756 A1, May 27, 2021
Int. Cl. C08G 73/10 (2006.01); B01D 67/00 (2006.01); B01D 71/02 (2006.01); B01D 71/64 (2006.01); C08G 85/00 (2006.01); C08K 3/34 (2006.01); H01M 10/0525 (2010.01); H01M 50/403 (2021.01); H01M 50/446 (2021.01)
CPC C08G 73/1082 (2013.01) [B01D 67/0011 (2013.01); B01D 71/028 (2013.01); B01D 71/64 (2013.01); C08G 73/1085 (2013.01); C08G 85/004 (2013.01); C08K 3/34 (2013.01); H01M 10/0525 (2013.01); H01M 50/403 (2021.01); H01M 50/446 (2021.01); B01D 2325/02 (2013.01)] 8 Claims
 
1. A method of preparing a composite membrane of zeolite and polyimide, the method comprising:
1) adding zeolite to an organic solvent, and dispersing the zeolite uniformly to obtain a zeolite dispersion; adding a diamine monomer and a dianhydride monomer to the zeolite dispersion, and carrying out condensation polymerization reaction between the diamine monomer and the dianhydride monomer in the presence of the zeolite to obtain a casting solution of polyamic acid, the casting solution being doped with zeolite; wherein the zeolite is present in an amount of between 1 wt. % and 5 wt. % of the zeolite dispersion; and the zeolite is at least one of MCM-41, NaY, NaA and ZSM-5;
2) coating a surface of a substrate with the casting solution obtained in 1) to form a liquid membrane; placing the liquid membrane in an environment with a humidity of between 70% and 90% for preliminary phase separation, and placing the liquid membrane in a coagulation bath for complete phase separation, thereby obtaining a composite porous membrane of zeolite and polyamic acid; and
3) Performing thermal imidization on the composite porous membrane of zeolite and polyamic acid obtained in 2) through gradient heating to obtain the composite membrane of zeolite and polyimide.