Process for Producing Phenol and/or Cyclohexanone

A process for producing phenol, the process comprising:

• (a) hydroalkylating benzene with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction product comprising cyclohexylbenzene;
• (b) contacting at least a portion of the cyclohexylbenzene from the hydroalkylation reaction product with an oxygen-containing gas in the presence of an oxidation catalyst under oxidation conditions effective to produce an oxidation effluent comprising cyclohexylbenzene hydroperoxide at a first concentration Con1 and residual cyclohexylbenzene;
• (c) concentrating at least a portion of the oxidation effluent to produce a cleavage feed comprising cyclohexylbenzene hydroperoxide at a second concentration Con2, where Con2>Con1;
• and
• (d) contacting a cleavage reaction mixture formed from the cleavage feed with a solid acid catalyst in a cleavage reaction zone under conditions effective to produce a cleavage product comprising phenol and cyclohexanone.