Metal-organic framework MOF-801/PIM-1 mixed-matrix membranes for enhanced CO2/N2 separation performance

This work mainly studies the CO2 separation performance of a new type mixed-matrix membranes (MMMs) based on MOF-801 as the microporous filler and PIM-1 as the polymer matrix. MMMs was successfully formed via simple casting/solvent evaporation approach at room temperature. The samples were systematically characterized by SEM, XRD, TGA and FTIR, the permeability-selectivity of MMMs to CO2, O2 and N2 was studied by gas permeability test. The experimental results show that the uniform dispersion of the CO2-philic MOF-801 filler provides a channel for the rapid and selective transport of CO2, so the MOF-801/PIM-1 MMMs revealed much higher CO2 permeability and CO2/N2 ideal selectivity (CO2 = 9686 Barrer, CO2/N2 = 27, all selectivity in the paper is ideal) than pure polymer membrane. After 90-days aging test, the CO2 permeability of MMMs remains above 70%, which reflects its good anti-aging performance. After 120 h continuous gas permeability test, it also shows good long-term working stability. The experimental results show that the good gas separation performance of MMMs exceeds the Robeson upper bound (2008), showing good application prospect for practical greenhouse gas CO2 separation.