Solvent influence on the textural properties and CO2/N2 separation performance of novel Pebax-1657/attapulgite mixed matrix membranes

Mixed matrix membranes (MMMs) have gained significant attention in CO 2 separation. However, the symmetrical dispersion of inorganic filler nanoparticles during MMMs fabrication is still a crucial challenge. The present work investigates the outcome of N-Methyl-2-pyrrolidone (NMP) and N-N-Dimethyl-formamide (DMF) solvents on MMMs texture, perm-selectivity and nanoparticles dispersion. Scanning electron microscopy (SEM), Fourier-transform-infrared (FTIR) and X-Ray Diffraction (XRD) analyses were also performed for membrane characterization. The MMMs fabricated with NMP solvent showed competitive CO 2 permeability (120.20 barrer) and CO 2 /N 2 selectivity (69.31) compared to the membranes prepared with DMF solvent. It has been indicated that the molar volume, boiling point and solubility parameters were significant factors in the solvent selection. Moreover, the effect of operating temperature on gas transport properties showed substantial impact in perm-selectivity, at 3 bar feed-pressure, with the temperature dropping from 40 °C to 0 °C, the CO 2 /N 2 gases selectivity increased from 69.31 to 105.50, equating to a 64.8% decrease in CO 2 permeability.