Hydrothermal Stability of Natural CXN Zeolite I. Factors of Influencing the Hydrothermal Stability

作者：He Qiuping^*; Cheng Xiaowei; Yao Hao; Long Yingcai

来源：Acta Chimica Sinica, 2009, 67(18): 2060-2066.

• CXN zeolite
• STI zeolite
• hydrothermal stability
• non-framework aluminum
• steam treatment

Some factors, such as calcination, ion-exchange, acid leaching etc., were studied on influencing the hydrothermal stability of natural CXN zeolite. Characterization with XRD, XRF and (27)Al MAS NMR proves that the type and location of cations obviously influence the hydrothermal stability of the zeolite, and NH(4)-type CXN zeolite possesses the best stability. Although the framework SiO(2)/Al(2)O(3) ratio of calcined NH(4)-CXN zeolite was enhanced, but the increase of followed framework defects greatly reduced the hydrothermal stability. The effects of steam volume, treatment temperature and time on the evolution rules of zeolite framework were also studied in this paper. The results indicate that raising the treatment temperature and steam volume decrease the zeolite crystallinity, while the effect of treatment time is negligible.

• 出版日期2009-9-28
• 单位复旦大学; 上海大学