Y and P zeolites were synthesized hydrothermally from natural stellerite under different conditions and were characterized via XRD and FT IR. The results show that the higher crystallinity of Y zeolite can be obtained...Y and P zeolites were synthesized hydrothermally from natural stellerite under different conditions and were characterized via XRD and FT IR. The results show that the higher crystallinity of Y zeolite can be obtained in hydrothermal system with low alkalinity, low Ca 2+ /Na + ratio, and high SiO 2/Al 2O 3 ratio. The lattice space of the samples decreases as crystallization time increases. P Zeolite is prompted under condition of higher alkalinity and higher Ca 2+ /Na + ratio. The intensity and number of bands in the range of 400?cm -1 ～ 900?cm -1 increases with reaction time. Bands at 680?cm -1 , 760?cm -1 and 860?cm -1 corresponding to Y zeolite appear during the crystallization stage. Most of these bands shift to higher wavenumbers when SiO 2/Al 2O 3 ratio increases generally. In the hydrothermal system with reverse condition above, bands at 600?cm -1 , 420?cm -1 ～ 470?cm -1 hardly change as the crystallization time increases and the main crystal phase of P zeolite is obtained.展开更多
文摘Y and P zeolites were synthesized hydrothermally from natural stellerite under different conditions and were characterized via XRD and FT IR. The results show that the higher crystallinity of Y zeolite can be obtained in hydrothermal system with low alkalinity, low Ca 2+ /Na + ratio, and high SiO 2/Al 2O 3 ratio. The lattice space of the samples decreases as crystallization time increases. P Zeolite is prompted under condition of higher alkalinity and higher Ca 2+ /Na + ratio. The intensity and number of bands in the range of 400?cm -1 ～ 900?cm -1 increases with reaction time. Bands at 680?cm -1 , 760?cm -1 and 860?cm -1 corresponding to Y zeolite appear during the crystallization stage. Most of these bands shift to higher wavenumbers when SiO 2/Al 2O 3 ratio increases generally. In the hydrothermal system with reverse condition above, bands at 600?cm -1 , 420?cm -1 ～ 470?cm -1 hardly change as the crystallization time increases and the main crystal phase of P zeolite is obtained.
