Gas separation performance of enhanced carbon molecular sieve (CMS) membranes rendered from two-step pyrolyzing process

摘要

Abstract: Carbon molecular sieve (CMS) membranes were prepared by two-step thermal treatment process. During this procedure, microcavity opening region was observed at 400 ~ 500 o C. High gas permeable polybenzoxazole (PBO) was obtained at this intermediate ranges. After that region, molecular sieving effect was strengthened with decrease of permeability than intermediate thermally treated membrane. Precise characterization was performed using spectroscopic and thermo gravimetric analysis. Microcavities obtained from thermal treatment and pyrolysis were characterized by N2 adsorption and desorption experiments. Obtained PBO and CMS membranes easily surpassed the upper limit for conventional polymer membranes and can be useful for membrane separation process at harsh conditions.