In a process for producing phenol, a cleavage feed comprising cyclohexylbenzene hydroperoxide is supplied to a cleavage reaction zone and a cleavage reaction mixture comprising the cleavage feed is contacted in the cleavage reaction zone with a solid acid catalyst under conditions effective to produce a cleavage effluent comprising phenol and cyclohexanone. The cleavage effluent is then divided into at least a cleavage product and a cleavage recycle and the cleavage recycle and a polar solvent is supplied to the cleavage reaction zone to produce the cleavage reaction mixture with the cleavage feed. Preferably, the polar solvent is combined with the cleavage recycle before being charged into the cleavage reaction zone.