Influence of functionalized SiO2 nanoparticles on the morphology and CO2/CH4 separation efficiency of Pebax-based mixed-matrix membranes

Silica (SiO2) nanoparticles were first functionalized using (3-aminopropyl) triethoxysilane (APTES) and then utilized as filler for the preparation of poly (ether-block-amide) (Pebax (R)-1074) based mixed-matrix membranes (MMMs). To characterize the modified nanoparticles and the prepared membranes, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA) were conducted. The influences of the pure and amine-modified nanoparticles content, and feed temperature and pressure on CO2 and CH4 permeability and ideal CO2/CH4 selectivity values of the membranes were studied. The permeation experiments exhibited that the incorporation of 12.5 wt% of amine-functionalized SiO2 nanoparticles into the Pebax matrix raises the CO2 permeability and ideal CO2/CH4 selectivity about 100 and 32%, respectively.