| 초록 |
All silica DDR (deca-dodecasil 3R) zeolite is a strong candidate for CO2 (0.33 nm) separation from N2 (0.364 nm) because its rigid pore structure with the size of 0.36 x 0.44 nm2 allows for separations via the differences in their molecular sizes. We conducted two parameter studies of the variation of silica sources (TMOS, TEOS, fumed silica and silica sol) for non-seeded growth and of the seed amount for seeded growth. For the former, we obtained all silica DDR (Si-DDR) zeolite particles from various silica sources and these particles were further used for the subsequent seeded growth. It was found that Si-DDR zeolite particles (2~6 µm), obtained by seeded growth, were smaller than those obtained by non-seeded growth and showed mono-dispersed diamond shape. Variation of seed amount was effective for controlling the particle size of Si-DDR zeolites. Though the Si-DDR zeolites particles were synthesized by conducting the secondary growth of different seeded particles, seeded growth resulted in the comparable CO2, N2, and H2O adsorption properties (~25, ~11-17 and 28-32 kJ•mol-1, respectively). |
