Study of the effect of inorganic particles on the gas transport properties of glassy polyimides for selective CO 2 and H 2 O separation

Abstract

Three polyimides and six inorganic fillers in a form of nanometer-sized particles were studied as thick film solution cast mixed matrix membranes (MMMs) for the transport of CO 2 , CH 4 , and H 2 O. Gas transport properties and electron microscopy images indicate good polymer-filler compatibility for all membranes. The only filler type thatdemonstrated good distribution throughout the membrane thickness at 10 wt.% loading was BaCe 0.2 Zr 0.7 Y 0.1 O 3 (BCZY). The influence of this filler on MMM gas transport properties was studied in detail for 6FDA-6FpDA in a filler content range from one to 20 wt.% and for Matrimid® and P84® at 10 wt.% loading. The most promising result was obtained for Matrimid®-10 wt.% BCZY MMM, which showed improvement in CO 2 and H 2 O permeabilities accompanied by increased CO 2 /CH 4 selectivity and high water selective membrane at elevated temperatures without H 2 O/permanent gas selectivity loss.