AlCl3/silica gel catalysts were prepared by inclosed grafting method in the autoclave and their catalytic activities for alkylation reaction of thiophene with olefins in benzene were studied. The gas chromatograph and chromatography-mass spectroscopy were used to quantitatively determine the thiophene in benzene and qualitatively measure the reaction products, respectively. XPS, SEM, EDX and N-2 adsorption techniques were used to characterize the physical and chemical properties of catalyst samples. The results show that AlCl3 can be effectively anchored by reacting with the silanol groups on silica gel surface to form the Si-x(OH)(y) (-) aOaAlCl(3 (-) (a)) species and the prepared AlCl3/silica gel catalyst possesses the significant activity for the alkylation reaction of thiophene and olefin. The preparation conditions, such as mass ratio of AlCl3/silica gel support, grafting temperature and time, and thermal treatment temperature of silica gel, have an important role on the content and distribution of active component over silica gel support, and thus affect the catalytic activity. The optimum preparation conditions of AlCl3/silica gel catalyst are that AlCl3 is grafted on silica gel support, which has been thermally treated at 400 degrees C for 3 h, and at 180 degrees C for 4 h with the mass ratio of 0.20 for AlCl3/silica gel support. The loading ratio of AlCl3 on silica gel can reach about 64 wt.% and the optimal conversion rate of thiophene in benzene is 94.23% when the ratio of liquid to catalyst is 20 mL/g. (C) 2013 Elsevier B.V. All rights reserved.