초록 |
CHA (Chabazite) zeolite membranes are effective for the separation of CO2 from N2 and CH4 via their regular micropores. In particular, a feature that the CHA membrane can secure its great separation performance under wet condition makes it an attractive candidate for a membrane-based carbon capture process. For the realization of practical use, we scaled up the CHA membrane by changing supports from flat discs to tubes. Thereafter, differences in the CO2 perm-selectivities were investigated via CO2/N2 and CO2/CH4 separation performance tests. The CHA membrane showed the separation factors as high as ~30 for CO2/N2 and ~200 for CO2/CH4 mixtures. In addition, ~75% CO2 recovery and ~60% CO2 purity could be achieved by the CHA membrane with respect to the CO2/N2 mixture having a molar ratio of 15:85 under wet condition. Finally, we correlated and derived a relationship between the convective mass transfer and the gas flow property of feed streams, resulting that the CO2 perm-selectivity of the CHA membrane was a strong function of the mass transfer resistance in the feed side. |