文献类型：期刊文献

英文题名：Preparation of a hollow HZSM-5 zeolite supported molybdenum catalyst by desilication-recrystallization for enhanced catalytic properties in propane aromatization

作者：Xu, Guohao[1];Zhang, Peng[1];Cheng, Junjun[1];Wei, Ting[1];Zhu, Xuedong[1];Yang, Fan[1]

机构：[1]East China Univ Sci & Technol, Engn Res Ctr Large Scale Reactor Engn & Technol, Minist Educ, Shanghai 200237, Peoples R China

年份：2021

卷号：300

外文期刊名：JOURNAL OF SOLID STATE CHEMISTRY

收录：;EI(收录号：20212310453844);WOS:【SCI-EXPANDED(收录号:WOS:000661134000026)】；

基金：This project was sponsored financially by the National Natural Science Foundation of China (No. 21776076).

语种：英文

外文关键词：Propane aromatization; Desilication-recrystallization; Hollow Mo/HZSM-5; Silicon-rich external surface

摘要：A hollow HZSM-5 supported molybdenum (Mo) catalyst was successfully prepared by desilication-recrystallization method of HZSM-5 in tetrapropylammonium hydroxide (TPAOH) solution. The as-synthesized catalyst exhibiting excellent performance in propane aromatization reaction was thoroughly investigated, along with the mechanism for the formation of hollow structure and mechanism for the deactivation. Results revealed that TPA(+) exerted a controllable desilication and recrystallization effect. Compared with Na2CO3 treatment which led to a mesoporous structure, TPAOH treatment was able to leach out the inner Si species by OH- and then those Si species recrystallized on the external surface, resulting in the hollow structure and a silicon-rich external surface. In addition, the hollow zeolite exposing higher external surface provided more anchoring sites for Mo species, which was beneficial to the Mo related Lewis acid sites but decreased the surface Bronsted acidity. At 823 K and a space velocity of 1800 mL.g(-1).h(-1), the hollow Mo/HZSM-5(TPAOH) catalyst behaved a propane conversion of 73.01% and aromatics selectivity of 77.36%, exceeding those of the hierarchical Mo/HZSM-5(Na2CO3) catalyst by 5.97% and 9.96%, respectively. These features of Mo/HZSM-5(TPAOH) granted it superb diffusion ability and optimized Bronsted/Lewis acid ratio (B/L = 1.3), which greatly enhanced the propane conversion and aromatic selectivity together with a preeminent catalytic stability.