Core–Shell HZSM-5@silicalite-1 Composite: Controllable Synthesis and Catalytic Performance in Alkylation of Toluene with Methanol

• Published in: Catalysis letters Vol. 150; no. 7; pp. 1923 - 1931
• Main Authors: Li, Guixian, Wu, Chao, Dong, Peng, Ji, Dong, Zhang, Yongfu
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-07-2020; Springer; Springer Nature B.V
• Subjects: Acids; Alkylation; Ammonia; Catalysis; Catalysts; Chemical synthesis; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Methanol; Morphology; Organometallic Chemistry; Paraxylene; Physical Chemistry; Selectivity; Silicalite; Toluene; Xylene; xylene; Core–shell catalyst; Acidity and selectivity; Toluene; Alkylation
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-019-03085-y

HZSM-5@silicalite-1 catalysts were prepared by the hydrothermal method, and the structure, morphology, acidity and pore texture of core–shell catalysts were studied by XRD, SEM, TEM, NH
3
-TPD, Py-IR and N
2
adsorption/desorption isotherms in detail. Their catalytic performances were tested in the alkylation reaction of toluene with methanol. The results showed that a coating layer was formed in the form of silicalite-1 on HZSM-5. NH
3
-TPD measurements indicated that HZSM-5@silicalite-1 contained less strong acid sites but more weak acid sites than the parent HZSM-5. The selectivity of
p
-xylene for toluene alkylation was approximately linear with the percentage of weak acid in total acid. Under the optimal reaction conditions, the conversion of toluene was 34.15%, and the selectivity of
p
-xylene was 96.77%.
Graphic Abstract