Sulfonated polyethersulfone-based membranes with different ion forms for high-performance gas separation

Abstract

The sulfonation of polymeric membrane materials is an effective method for advancing membrane-based gas separation performance. Two types of sulfonated polyethersulfone (SPES) polymers with different degrees of sulfonation (DS) were synthesized by adjusting the used amount of chlorosulfonic acid. The SPES-H membranes exhibited a decrease in the permeability and an increase in the selectivity with increasing the degree of sulfonation because of the effect of electrostatic crosslinking. The SPES-Zn membrane exhibited the best gas separation performance. Compared with flat dense PES membranes, the SPES-Zn membrane displayed impressive permselectivity increments of ∼ 140%, 86%, 18%, and 57% for He/N2, H2/N2, O2/N2, and CO2/CH4 gas pairs, respectively. The newly developed SPES membranes with different ion forms showed high resistance to the CO2-induced plasticization and a comparably high CO2/CH4 selectivity in pure gas and mixed gas measurements. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).