(646h) Sod-Zmof/Polyimide MIXED-Matrix Membranes for CO2 Separation

Polymer/MOF mixed matrix membranes offer enhanced gas sepration performance compared to neat polymeric membranes. In designing such membranes, the selection of polymer/MOF pairs is of crucial importane. Polyimides have been of interest as polymeric gas separation membranes for a long while due to their thermal and mechanical properties. On the other hand, eeolite-like metal organic frameworks (ZMOFs), which are a subclass of MOFs, are promising candidates for separation and purification applications. They have extra-framework ions in the pores of molecular dimensions increasing the interactions with guest molecules and improving their separation, storage, or ion-exchange capability. The charge-compensating extra-framework ions inside the cavities of ZMOFs can be ion-exchanged with alkali metals and this is expected to increase their affinity for CO₂ and improve the CO₂ separation performance of polyimide based mixed matrix membranes for gas mixtures like natural gas (CO₂/CH₄) and flue gas (CO₂/N₂).

In this work, as-synthesized and alkali ion-exchanged sod-ZMOF nanoparticles were used to develop polyimide/ZMOF mixed matrix membranes. Two different types of polyimides (Matrimid^® 5218 and 6FDA-DAM) and one copolyimide (6FDA-BTDA-pBAPS) were chosen for this purpose. After the analyses of structural and thermal characteristics of the prepared membranes; CO₂/CH₄ and CO₂/N₂ separation performance of the membranes were tested in terms of CO₂/CH₄ and CO₂/N₂ separation performances via single and mixed gas permeability measurements.

This work is part of the project supported by the Scientific and Technological Research Council of Turkey (TUBITAK) through the grant no. 113M776.