AI Sha·NuLaHong1,2, LIU Jiaxu1, ZHAO Wenping1, WANG Guiru1, GUO Hongchen1
(1. State Key Laboratory of Fine Chemicals, Department of Catalytic Chemistry and Engineering, Dalian University of Technology, Dalian 116024, China; 2. College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, China)
Abstract: The conversion of n-butane and i-butane over HZSM-5 and Zn/HZSM-5 catalysts were evaluated with mini-scale pulse reactor in terms of reactivity and aromatization selectivity. Results show that, i-butane has higher conversion than n-butane at 550℃ on both HZSM-5 and Zn/HZSM-5 catalysts, however, the aromatics selectivity of i-butane is lower than that of n-butane. Demethylation is the main path of n-butane and i-butane activation, and which is also an important factor to affect aromatization selectivity. Zinc modificatioin remarkably increases the conversion of i-butane and n-butane and, at the same time, promotes their demethylation activation. When the mixture of n-butane and i-butane were used as feedstock, no difference is seen in terms of n-butane and i-butane conversions compared with the pure butane feedstocks, which implies that there is no obvious competition between n-butane and i-butane during adsorption activation and subsequent reactions. Nano-ZSM-5 zeolite is beneficial to the conversion of i-butane due to its small grain size, short channel and lower diffusion resistence.
Key words: butane aromatization; nano-HZSM-5; zinc modifycation; mini-scale pulse reactor.
E-mail: aisa705@yahoo.cn,hongchenguo@163.com
Journal of Molecular Catalysis, Vol. 26, Issue 3, 2012,257-264
