PREPARATION OF POLYCARBONATE METAL SALT GAS SEPARATION MEMBRANES

Polycarbonate (PC) membranes possess high O2/N2 selectivity and mechanical strength, but have low gas permeability. In order to improve the pure PC membrane's gas permeability and selectivity Of O2/N2, in this study we attempt to combine transition metal salts into the membrane to form a complex membrane..Tensile strength and elongation at break of the membrane are not significantly changed. The effect of casting solution composition and solvent evaporation time on morphology, gas permeability, and selectivitY Of O2/N2 of PC membranes are studied. The gas permeabilities of PC/DMF/Metals membranes are significantly improved, as compared to those of pure PC membrane. For example, an oxygen permeability of 137 cm3 (STP)-cm/cm-sec-cmHg and separation ratio of oxygen to nitrogen of 4.0 for PC/DMF/CuCl2 membrane with [PC/CH2Cl2]/[CuCl2/DMF] = 17/3 mL/mL, and CuCl2/DMF = 0.1 g/mL, can be obtained. The FT-IR spectra and elementary analysis suggest that there is interaction among metal, DMF, and PC.