In a process for producing cyclohexylbenzene, benzene is reacted with cyclohexene under alkylation conditions effective to produce an alkylation effluent comprising cyclohexylbenzene and a polycyclohexylbenzene. A first feed comprising at least a portion of the alkylation effluent is then fed to a first separation device, where the first feed is separated into at least a first fraction containing cyclohexylbenzene and a second fraction containing the polycyclohexylbenzene, the second fraction also comprising an oxygenated hydrocarbon. At least a portion of the oxygenated hydrocarbon is removed from at least a portion of the second fraction in a second separation device to obtain a second feed. The second feed may then be reacted in a transalkylation or dealkylation reactor to convert at least part of the polycyclohexylbenzene to additional cyclohexylbenzene.