STUDY ON EFFECTS OF SiO2/Al2O3 RATIO OF HZSM-5 ZEOLITES ON n-BUTANE CRACKING

Abstract

Abstract: The HZSM-5 zeolites with different mole ratio of SiO2/Al2O3 were characterized by in-situ FT-IR and their n-butane cracking activities were investigated in a continuous flow fixed-bed micro-reactor to reveal the relationship between Si/Al ratio, active sites and catalytic behavior. The results indicated that the kind，number， and strength of active sites of HZSM-5 zeolites with Si/Al ratio of 38 and 200 were significantly different. HZSM-5-38 zeolites have more acid bridging Si-O（H）-Al groups and non-skeleton aluminum hydroxyl with strong acidity, while，HZSM-5-200 zeolites only show several isolated hydroxyl groups with small amount of weakly acidic or non-acidic neighbouring silica hydroxyl groups in microporous. HZSM-5-200 zeolites result in higher yield of light olefins, indicating that lower acid density and strength is suitable for producing more olefins.

Key words: HZSM-5, Active site, in-situ FT-IR, cracking

CLC Number:

Zhang Wenfang Wang Pengzhao Zhang Minxiu Yang Chaohe Li Chunyi. STUDY ON EFFECTS OF SiO2/Al2O3 RATIO OF HZSM-5 ZEOLITES ON n-BUTANE CRACKING[J]. Petroleum Processing and Petrochemicals, 2019, 50(3): 48-53.

References

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