HY zeolite promoted liquid-solid free-solvent alkylations of a-methyl naphthalene with long chain olefins have been performed in intermittent reactor. Effects of various reaction conditions like reaction temperature, dosage of catalyst and reaction time on the alkylation reaction were investigated. The alkylations were also carried out over alkaline earth and rare earth metal oxide modified HY, and effects of impregnated amount on the reactions were investigated simultaneously. It is found that 0.5% of La,03 modified HY exhibits outstanding catalytic performances, 94.0% of conversion for olefins and 100% of selectivity for the desired products were achieved. Moreover, the generation and reusability of deactivated HY zeolite catalyst were also studied. Results show that the catalytic performances of deactivated catalyst can be refreshed completely, and the regenerated catalyst can be further reused many times without decrease in its catalytic activity. (c) 2005 Elsevier B.V. All rights reserved.