关键词: 催化裂化, 催化剂, 稳定性, 分子筛, 气相超稳法

Abstract: In order to improve the stability and activity of zeolites，the active component of FCC catalyst, five kinds of high stabilized zeolites HSZ-1，HSZ-2，HSZ-3，HSZ-4，HSZ-5 with different cell sizes were designed and manufactured by changing the degree of cation exchange and gas phase super stable modification of zeolites. The structure and performance of the five kinds of high stabilized zeolites were analyzed by X-ray diffraction（XRD）, N2 adsorption desorption（BET） and Fourier transform infrared spectroscopy（FT-IR）techniques. The results showed that the developed high stabilized zeolites possessed the properties of high crystallinity，large specific surface area，high thermal stability and hydrothermal stability. Moreover, with the increase of the degree of super stable modification of zeolites, the cell constant of zeolites decreased, the content of SiO2 increased, the total acid quantity and the ratio of B/L ratio decreased, the amount of small cage hydroxyl decreased, the amount of terminal silicon hydroxyl increased, however the large cage hydroxyl group of the zeolites were all well preserved. In addition, HSZ series zeolites all contained four-coordinative framework aluminum and six-coordinative extra-framework aluminum species. The increase of the degree of super stable modification increased the content of extra-framework aluminum species; in addition to the four kinds of Si coordination states, HSZ-1 zeolite with the highest hyperstability also contains Si fragments.

Key words: catalytic cracking, catalyst, stability, zeolites, gas-phase stablization