| Summary: | 碩士 === 中原大學 === 化學工程研究所 === 105 === Carbon molecular sieve membranes (CMSMs) were regarded as one of the promising membrane for gas separation because of its outstanding separation performance. The industrial application of CMSMs was limited by its chemical aging. In this study, the degree of chemical aging was decreased using air post-treatment. It was fabricated through pyrolyzing Kapton at 800°C followed by an air post-treatment at different temperature and exposure time. XRD analysis confirmed that the d-spacing of CMSMs was increased after air post-treatment. BET analysis demonstrated that post-treated membranes have higher BET and Langmuir surface area than that of untreated CMSMs. PALS analysis indicated that pore diameter was increased after air post-treatment. Gas sorption isotherm showed that the decrease of adsorption capacities of post-treated CMSMs was due to the decrease of active sites, leading to lower degree of aging. Gas separation test revealed that air post-treatment may enhance the gas permeability and reduce the degree of aging of CMSMs. CMSMs was post-treated at 400℃ for 5h and after 1 month aging, it had higher CO2 permeability and considerable CO2/N2 selectivity (P=56barrer, α=147) than the untreated CMSMs (P=28barrer, α=186).
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