In a process for producing cyclohexanone, cyclohexylbenzene is oxidized to produce cyclohexylbenzene hydroperoxide and then the resultant cyclohexylbenzene hydroperoxide is cleaved to produce an effluent stream comprising phenol and cyclohexanone. At least a portion of the effluent stream is then fed to at least one hydrogenation reaction zone, where the effluent stream portion is contacted with hydrogen in the presence of a hydrogenation catalyst under conditions effective to convert at least part of the phenol in the effluent portion into cyclohexanone.