NaY-type zeolite membranes were synthesized on a porous support tube by a hydrothermal process. The membranes were ion-exchanged with Li+ and K+ ions, and permeances through the membranes were determined for an equimolar mixture of CO2 and N2, as well as for single-components thereof, at a temperature range of 0-400°C. The permeance to CO2 showed a maximum at 100°C, but CO2/N2 selectivity decreased with increasing temperature. The zeolite membranes that were exchanged with K+ and Li+ ions gave higher and lower CO2/N2 selectivities, respectively, than were found for the NaY-type membrane. The permeation properties of the ion-exchanged zeolite membranes were analyzed using a sorption-diffusion model. The high CO2/N2 selectivity of the K-exchanged membranes can be explained by the decrease in N2 sorptivity for the mixed feed.
All Science Journal Classification (ASJC) codes
- Environmental Engineering
- Chemical Engineering(all)