Development of solid polymer composite membranes based on sulfonated fluorocopolymer for olefin/paraffin separation with high permeability and selectivity

The PFSA-PP composite membrane was fabricated by deposition of a selective Nafion (R)-type poly(perfluorosulfonic acid) (PFSA) layer on a highly porous polypropylene (PP) film. The possibility of ethylene/ethane mixtures separation with the use of hydrogen and silver forms of the membrane was studied. A considerable influence of the gas mixture humidity on the ethylene permeability and selectivity of the membranes was demonstrated. The ethylene/ethane mixture separation factor reached 514, which is close to the values attained for Nafion (R) membranes, but with higher ethylene gas permeance of 28 GPU. The decrease in the selective layers thickness from 11 to 1 mu m increases the ethylene permeance to 94.5 GPU with simultaneous decrease in the selectivity. As the ethylene content in the mixture decreases, the separation factors increase markedly.

Automated summary

The PFSA-PP composite membrane showed a high separation factor in the separation of ethylene/ethane mixtures, with the gas mixture humidity having a significant impact on membrane performance. Additionally, a decrease in the thickness of the selective layer resulted in increased ethylene permeance.