| 초록 |
All-silica DDR zeolites (Si-DDR) with a pore size of 0.36 × 0.44 nm2 are considered as a potential material for the separation of CO2 (0.33 nm) from N2 (0.364 nm) by their size difference. However, the difficulty of synthesizing uniform-sized DDR zeolite has suppressed the utilization of DDR zeolite as CO2 separators. Here, we found that uniform-sized and diamond-like Si-DDR particles obtained by seeded growth from irregular Si-DDR particles, synthesized by non-seeded growth. Adsorption isotherms of CO2, N2, and H2O in Si-DDR particles and their heats of adsorption were similar to the literature data. The estimated CO2/N2 ideal sorption and permeation selectivity were ~15.3-18.0 and ~7.7-9.0 at 303 K, respectively, and corresponding data indicated potential as adsorbents and membrane for CO2/N2 separations. Also, the H2O adsorption was affected by the defect, and more strongly, on the number of Al species incorporated in the DDR zeolite framework |
