Gas separation membranes based on fluorinated and perfluorinated polymers

摘要

A process for separating components of a gas mixture using gas-separation copolymer membranes. These membranes use a selective layer made from copolymers of an amorphous perfluorinated dioxolane and a fluorovinyl monomer. The resulting membranes have superior selectivity performance for gas pairs of interest while maintaining fast gas permeance compared to membranes prepared using conventional perfluoropolymers such as Teflon® AF, Hlyflon® AD, and Cytop®.

主权项

1. A process for separating two components, A and B, of a gas mixture having a ratio (Rf) of A:B, comprising:
(a) passing the gas mixture across a separation membrane having a feed side and a permeate side, the separation membrane having a selective layer comprising a copolymer consisting of a perfluorinated dioxolane monomer and a fluorovinyl monomer selected from one of the following formulas:
F2C═CFR, where R is H, C1, a C1 -C6 perfluoroalkyl, or OX. where X is a C1-C6 perfluoroalkyl or a C1-C12 perfluorooxyalkyl having one or more ether groups,orH2C═CR1R2, where R1 is F, H, C1-C6 perfluoroalkyl, or OX, or where X is a C1-C6 perfluoroalkyl or a C1-C12 perfluorooxyalkyl having one or more ether groups, and R2 is F, C1-C6 perfluoroalkyl, or OX, or where X is a C1-C6 perfluoroalkyl or a C1-C12 perfmorooxyalkyl having one or more ether groups, (b) providing a driving force for transmembrane permeation; (c) withdrawing from the permeate side a permeate stream having a ratio (Rp) of A:B, where Rp>Rf; and (d) withdrawing from the feed side a residue stream having a ratio (Rr) of A:B, where Rr