| 초록 |
Siliceous deca-dodecasil 3 R (Si-DDR) zeolites have pore size of 0.36 × 0.44 nm2. This is desirable for separating CO2 from N2 based on size differences. Despite the potential of the DDR zeolite as CO2 separators, the synthetic methods that allow DDR zeolite particles have not been systematically investigated. we found that a seeded growth of irregular Si-DDR zeolite particles, obtained by non-seeded growth, resulted in homogeneous and diamond-like Si-DDR particles. Adsorption isotherms of CO2, N2, and H2O, the 3 main components in the flue gas from coal-fired power plants, in Si-DDR particles and the corresponding heats of adsorption were comparable. The resulting adsorption and permeation selectivity of CO2/N2 were estimated and indicated that Si-DDR zeolites can serve as adsorbents and membranes for CO2 separation. The H2O adsorption depends strongly on the concentration of defects present in the Si-DDR zeolite and more considerably on Al species integrated into the DDR zeolite. |
