A new ternary mixed-matrix membrane (PEBAX/PEG/MgO) to enhance CO2/CH4 and CO2/N2 separation efficiency

Mixed-matrix membranes (MMMs) composed of suitable CO2-philic polymers and fillers can be attractive candidates for CO2/CH4 and CO2/N-2 separation due to their high CO2 permeability, good thermochemical stability, low fabrication cost, and fast production process. In this research, a novel ternary MMM was fabricated via the blending of poly (amide 12-b-ethylene oxide) (PEBAX-1074) with polyethylene glycol (PEG-200) and magnesium oxide (MgO) nanoparticles mixture. The effects of various loadings of the fillers on CO2, N-2, and CH4 permeability values through the membranes were studied. Permeation of CO2, N-2, and CH4 gases through the resultant membranes at pressures of 2, 4, 6, 8, and 10 bar and temperatures of 25, 35, 45, and 55 degrees C revealed the superiority of the MMMs for CO2/CH4 and CO2/N-2 separation in comparison with the pristine membranes. Particularly, at 25 degrees C and 2 bar, the CO2 permeability, as well as ideal CO2/CH4 and CO2/N-2 selectivity of the optimized MMM containing 40 wt% of PEG-200 and 8 wt% of MgO nanoparticles, rose to 210.1 Barrer, 24.9 and 60.9, corresponding to enhancement of around 225%, 23% and 24% of the CO2 permeability and selectivity compared to the neat membrane, respectively. Thus, the fabricated MMM has a satisfying potential to separate CO2 from N-2.