A process for alkylating an alkylatable aromatic compound is disclosed, in which the process includes: (a) contacting the alkylatable aromatic compound and an alkylating agent with an alkylation catalyst under alkylation conditions; and (b) when said alkylation catalyst has become at least partially deactivated, contacting said alkylation catalyst with a C1-C8 hydrocarbon under alkylation catalyst reactivation conditions. The process provides comparable rejuvenation of catalyst activity as air rengenaration with minimal or no increase in amounts of undesirable byproducts such as polypropylbenzenes in the case of benzene alkylation with propylene.