Preparation ofAl2O3/PDA/Pebax membrane modified by (C3NH2MIm)(PF6) for improvingCO2separation performance

Abstract

AbstractMixed matrix membranes (MMMs) are currently the focus of research due to their possible high separation performance in separating CO2process. However, inorganic nanomaterials are easy to agglomerate so as to affect CO2separation performance. In order to overcome the agglomeration of nanomaterials in MMMs, a new filler, Al2O3/PDA‐TIL, was prepared, in which ionic liquid (TIL) was introduced on the surface of nano‐Al2O3by TIL grafting polydopamine coated on aluminum oxide. And a new type of Al2O3/PDA‐TIL/Pebax MMMs membrane was prepared by the blend of new fillers and Pebax. The properties of MMMs prepared were characterized by SEM, FTIR, XRD, XPS, etc. Results showed that TIL had reacted with PDA to form Schiff base structure, indicating that TIL had been successfully grafted onto PDA coated on Al2O3. As a result, TIL on the surface Al2O3successfully reduced the agglomeration of Al successfully reduced the agglomeration of Al2O3in the membrane and improved the separation of CO2. The gas permeability test results showed that the CO2permeability of MMMs increased from 60.69 Barrer to 101.12 Barrer, and the CO2/N2selectivity increased from 49.34 to 79 at 30°C and 0.1 MPa. Therefore, Al2O3/PDA‐TIL/Pebax membrane has a good application prospect in CO2separation process.