Fabrication and characterization of composite membranes for gas separation

Abstract

This work has made a series of initiative attempts at fabricating advanced composite membrane for gas separation. For the neat Matrimid/PES dual-layer composite hollow fibers produced in this work, the selective skin thickness was less than 0.3 I?m which is the thinnest ever reported. The composite membrane comprised zeolite KY entities incorporated in carbon molecular matrix yielded very attractive separation efficiency, capitalizing on the property of the zeolites and the thermal stability of the inorganic materials. In the investigation of fabricating hollow fibers with polymer/zeolite mixed matrix selective skin, it was first found that the distribution density of nano-sized zeolites in the selective skin of the dual-layer hollow fibers increased tremendously with increasing air gap; the efforts at revitalizing and further improving the performance of these hollow fibers were concentrated on eliminating interface defects through a novel p-xylenediamine/methanol soaking, thermal treatment, and a new reactive coating.