| 초록 |
All-silica DDR (decadodecasil 3R, Si-DDR) zeolites have a pore size of 0.36 × 0.44 nm2 suitable for separating CO2 (0.33 nm) from N2 (0.36 nm) by size of molecules. However, due to the difficulty of synthesizing mono-dispersed DDR particles, there have been few rigorous researches about the synthesis and control of the particle sizes. We have fabricated mono-dispersed diamond-like Si-DDR particles through seeded growth from irregular Si-DDR particles synthesized by non-seeded growth. Adsorption isotherms of CO2, N2, and H2O in the synthesized DDR particles and corresponding heats of adsorption were measured and compared with literature data. The resulting CO2/N2 ideal sorption indicated that Si-DDR zeolites are highly desirable to be used as adsorbents and membranes for CO2/N2 separations. In addition, we obtained the water adsorption data of the DDR particles containing Al species to study the effects of defects and Al in the DDR particles on water adsorption. |
