Facile surfactant-assisted synthesis of nanosheet-like mesoporous SAPO-34 zeolites and catalysis performance for methanol to olefins

• Published in: Reaction kinetics, mechanisms and catalysis mechanisms and catalysis, 2022-08, Vol.135 (4), p.1987-1998
• Main Authors: Nan, Yongyong, Ma, Shizi, Zha, Fei, Tian, Haifeng, Tang, Xiaohua, Chang, Yue, Guo, Xiaojun
• Format: Article
• Language: English
• Subjects: Catalysis; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Physical Chemistry
• ISSN: 1878-5190; 1878-5204
• DOI: 10.1007/s11144-022-02233-7

Nanosheet-liked mesoporous SAPO-34 zeolites were synthesized by a facile surfactant-assisted hydrothermal synthesis method. Compositions, morphology, acidities, chemical environment and texture properties of SAPO-34 zeolites synthesized were characterized by XRD, SEM, TEM, AFM, NH 3 -TPD, N 2 adsorption–desorption, XPS, and TG measurements. The morphology and the surface acid density of SAPO-34 zeolite can be controlled by adding of cetyltrimethylammonium bromide (CTAB) and using triethanolamine (TEA) as the template. The nanosheet-liked mesoporous SAPO-34 zeolites have lower amount of strong acid strongth with the thickness of about 3.0 nm. The catalysis performance for methanol-to-olefin (MTO) over nanosheet-like SAPO-34 zeolites was systematically studied. Under the condition of temperature at 400 °C, feeding WHSV of 2.0 h −1 , catalyst mass of 0.2 g and at atmospheric pressure, the methanol conversion is nearly 100% and the light olefins selectivity is 97.35%. As nanosheet-like SAPO-34 zeolites shorten the diffusion path and enhance the mass flow to and away from the catalytic centers, the catalyst lifetime is more than 420 min.