Direct synthesis of H type ZSM-5 in shaped form and catalytic properties in methanol-to-hydrocarbon reaction

• Published in: Journal of porous materials Vol. 29; no. 4; pp. 1165 - 1175
• Main Authors: Bu, Lingzhen, Wang, Yaquan, Sun, Chao, Zhao, Taotao, Zhao, Jingjing, Wang, Ziyang, Liu, Wenrong, Lu, Jiaxin, Wu, Shuhui, Shi, Mingxue
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2022; Springer Nature B.V
• Subjects: Aluminum oxide; Catalysis; Characterization and Evaluation of Materials; Chemical synthesis; Chemistry; Chemistry and Materials Science; Hydrocarbons; Ion exchange; Lewis acid; Methanol; Physical Chemistry; Production costs; Selectivity; Silicon dioxide; Zeolites; H-ZSM-5; Shaped form; Direct synthesis; Methanol to hydrocarbon
• ISSN: 1380-2224; 1573-4854
• DOI: 10.1007/s10934-022-01241-1

HZSM-5 zeolites as catalysts are conventionally synthesized through three steps: (1) preparation of Na type zeolites; (2) ion exchange into NH 4 type; (3) calcination. In this work, binder-free HZSM-5 zeolites with SiO 2 /Al 2 O 3 ratios of 50–170 were directly synthesized in the shaped form. The acid properties and pore structures of the HZSM-5 samples were appreciably affected by the SiO 2 /Al 2 O 3 ratio. In addition, these HZSM-5 samples had well preserved micropore structure, and even exhibited superior properties to the conventional one in methanol to hydrocarbon reaction with about 13% higher yield of C 5+ hydrocarbons and 63% higher aromatic selectivity. The improved catalytic performance might be attributed to the shortened b-axis, more acid sites, stronger acidity and higher Bronsted to Lewis acid ratios. More importantly, this synthesis method not only greatly simplifies the synthesis process of shaped HZSM-5 zeolites, but also reduces pollution and production cost.