A process for alkylation of benzene, including: feeding benzene, a polyalkylate, and a catalyst to a reactor comprising a first and a second reaction zone; reacting the benzene and the polyalkylate in the first reaction zone under transalkylation conditions to form a monoalkylate product; feeding a C.sub.2-C.sub.4 olefin to the reactor intermediate the first and second reaction zones; reacting benzene and the C.sub.2-C.sub.4 olefin in the second reaction zone under alkylation conditions to form additional monoalkylate product; recovering an effluent from the reactor, wherein the effluent comprises benzene, the monoalkylate product, any unreacted C.sub.2-C.sub.4 olefins, heavy hydrocarbons, and the catalyst; separating the catalyst from the effluent; separating the benzene from the monoalkylate product and the heavy hydrocarbons within the liquid effluent; separating the monoalkylate product from the heavy hydrocarbons within the liquid effluent; and recovering the monoalkylate product.