Development of mixed matrix membranes for gas separation application

Abstract

Organic-inorganic composites have received world-wide attention during last two decades because they may potentially offer superior performance in terms of gas/liquid separation. Basically, polymer-molecular sieve composites are formed by incorporating a molecular sieve into a polymer matrix, thus synergizing the properties of two components. We have studied the fabrication and characterization of flat dense and dual-layer hollow fiber polymer-zeolite mixed matrix membranes (MMMs) with and without the silane modification of zeolite surface in this study. The zeolites were commercial zeolites 3A, 4A, 5A and self-synthesized zeolite beta, while the glassy polymer was polyethersulfone (PES). Compared with neat polymer membranes, these MMMs possessed the enhanced gas separation performance, especially after the silane modification. A new modified Maxwell model was proposed in this study. It took the combined effects of polymer chain rigidification and partial pore blockage of zeolites into calculation. The new model showed much consistent performance predication with experimental data.