Permselectivities of ZIF-8 In Different Polymer Matrices and In ZIF-8/UltemŽ Mixed Matrix Hollow Fiber Membranes for Gas Separations

Permselectivities of ZIF-8 in Different Polymer Matrices and in ZIF-8/Ultem® Mixed Matrix Hollow Fiber Membranes for Gas Separations

Y. Labreche, J.R. Johnson, R.P. Lively, J. A. Thompson, D. Eiras, D.S. Sholl, W.J. Koros

Georgia Institute of Technology

School of Chemical & Biomolecular Engineering

Atlanta, GA

 

Abstract

Mixed matrix membranes are hybrid materials that have been explored recently to improve separation performance beyond limits that are achievable using pure polymeric materials.  Despite potential advantages, few reported cases consider successful extension of these hybrid materials in asymmetric hollow fiber morphologies.  Permselectivities of ZIF-8, a potential metal organic framework with utility for mixed matrix application, are reported here in different polymer matrices.   Moreover, we report the first successful production of mixed matrix asymmetric hollow fiber membranes containing metal-organic-framework (MOF) fillers.  Specifically, we describe the incorporation of ZIF-8 into a polyetherimide (Ultem® 1000) matrix, including a dual-layer (composite) asymmetric hollow fiber members formed via the dry jet-wet quench method.  The outer separating layer of these composite fibers contains 17 vole% of ZIF-8 filler, and these membranes are characterized over a range of temperatures and pressures for a variety of gas pairs.  An increase in separation productivity and efficiency for multiple gas pairs (e.g., CO₂/N₂, CO₂/CH₄) has been observed.  Furthermore, these membranes were tested using humid gas feeds (representing flue gas) wherein additional increases in membrane efficiency were also observed.

Acknowledgement

This project is funded by the ARPA-E IMPACCT Program via award DE-FOA-0000208.