The effect of Cu-BTC metal–organic framework (MOF) in mixed matrix membranes on permeability and separation of carbon dioxide and methane

Abstract

This research was conducted aimed to investigate the performance of mixed matrix membranes including polysulfone (PSF) and poly (ether sulfone) (PES) as polymers and cooper (II)-benzene-1, 3, 5-tricarboxylate (Cu-BTC) as filler with different blend ratios. The response surface methodology (RSM) was employed to design the experiments. The permeation of CO2 and CH4 gases was measured at a feed pressure of 3–9 bar. Morphology, thermal stability, spectral properties and mechanical properties of the membranes were evaluated by SEM, TGA, FTIR, XRD and tensile tests, respectively. According to the results, an increase in the pressure led to a gradual fall in the permeability of CO2 and CH4. Thermal and mechanical stability of the membranes increased by the addition of nanoparticles and polymers to the pure PSF and PES membranes, molecular interaction between the two polymers and MOF was observed by FTIR analysis. The morphology of the membranes was homogenous and good disperse of MOF in matrix polymer. Gas permeability studies indicated that the permeation and ideal selectivity were improved by 100% and 34% with the addition of the Cu-BTC (20%) and PES (73%) in the PSF matrix. It was concluded that synthesized PSF/PES/CUBTC mixed matrix membranes provided an optimized performance with a good combination of permeability, selectivity.