Reductive alkylation process

A monocycloalkyl aromatic hydrocarbon, e.g. cyclohexyl benzene, or a substituted monocycloalkyl aromatic hydrocarbon is prepared by a hydroalkylation process in which respectively an aromatic hydrocarbon, e.g. benzene, or an alkyl substituted aromatic hydrocarbon is contacted with hydrogen in the presence of a catalyst comprising ruthenium and nickel supported on zeolite beta. Optionally the catalyst can also include a rare earth metal, e.g. lanthanum.