Gas separation using mixed matrix membranes containing functionalized silica nanoparticles

The main goal of this study is to investigate the influence of functionalization of silica nanoparticles on the structural properties and gas separation performance of the poly (ether-block-amide) based mixed matrix membranes containing silica nanoparticles. For this purpose, first silica nanoparticles were modified by carboxylic functional groups and used for the preparation of mixed matrix membranes. The prepared membranes were analyzed using the XRD, DSC, FTIR, SEM and gas permeation tests. The results showed that the chemical modification of silica nanoparticles and the incorporating of carboxyl groups on its surface had a strong interaction with the polymer matrix and improved the filler distribution in the membrane matrix. It was observed that by loading 4%wt of silica nanoparticles functionalized with carboxyl groups in the polymer matrix increases the gas permeability at different pressures. The membranes containing 4%wt modified silica nanoparticles had the permeability of CO2, O2 and N2 equal 43.1, 2.8 and 0.42 Barrer, respectively, and the selectivity of O2/N2 (6.71) and CO2/N2 (103.3) at the pressure of 3 bar.