Gas separation properties of swelled nanocomposite chitosan membranes cross-linked by 3-aminopropyltriethoxysilane

Chitosan/APTEOS mixed matrix membranes with 5, 10, 20wt% loading of APTEOS were synthesized using solution casting method to improve gas separation properties of membranes. Chitosan concentration was varied from 1 to 2.5wt% to obtain best concentration of chitosan. CO2 and N-2 permeabilities and CO2/N-2 selectivity increased with feed pressure and APTEOS content up to 10 wt% and then decreased by the increase in APTEOS loading from 10 to 20wt%. The membranes with 10wt% content of APTEOS at 14bar showed the best CO2 permeability and CO2/N-2 selectivity of 79.3 barrer and 84.38, respectively. FTIR and SEM results revealed appropriate distribution of nanoparticles in the polymeric matrix, and AFM analysis showed that the roughness of the membrane surface increased significantly by APTEOS content.