| 초록 |
In industrial adsorptive cyclic processes, pelletized zeolites are widely applied, instead of powder zeolites, because of pressure drop in a bed. Therefore, the understanding of adsorption kinetics of pelletized zeolites is important to design efficient adsorption processes. In the study, the adsorption kinetics of CO2, CO, N2, and CH4, which are the main components in various effluent gases, on pelletized zeolite 13X was measured via a volumetric method at 293, 308 and 323 K. The experimental uptake curves were correlated with a non-isothermal diffusion model because the adsorption kinetics was controlled via heat generation and transfer. Adsorption rates of the gases on pelletized zeolite 13X were affected by the heat of adsorption, heat transfer rate and adsorption affinity. At the same temperature and pressure, the sequence of the effective diffusional time constant revealed the following sequence: CH4≒N2＜CO＜CO2, showing pressure and temperature dependency. While the diffusion rates of CO and N2 were controlled via micropore diffusion, CO2 and CH4 were significantly affected by macropore diffusion due to high heat transfer resistance. The results could contribute to designing adsorptive processes using zeolite 13X for CH4 recovery and CO2 capture from various effluent gases. |
