A process for producing biphenyl compounds, the process comprising: (a) contacting a hydroalkylation feed comprising C n aromatic hydrocarbons with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction effluent comprising (i) C 2n cycloalkylaromatic compounds and (ii) C n saturated cyclic hydrocarbons, wherein n is an integer from 6 to 12; (b) providing at least a portion of the hydroalkylation reaction effluent to a first dehydrogenation zone, therein dehydrogenating at least a portion of the C 2n cycloalkylaromatic compounds and at least a portion of the C n saturated cyclic hydrocarbons in the presence of a first dehydrogenation catalyst under conditions effective to produce a first dehydrogenation reaction product comprising (i) a mixture of C 2n biphenyl compounds; (ii) recovered C n aromatic hydrocarbons; and (iii) unreacted C n saturated cyclic hydrocarbons; (c) separating the first dehydrogenation reaction product into (i) a heavy dehydrogenation stream rich in the C 2n biphenyl compounds, and (ii) a light dehydrogenation stream rich in the recovered C n aromatic hydrocarbons and the unreacted C n saturated cyclic hydrocarbons; (d) providing at least a portion of the light dehydrogenation stream to a second dehydrogenation zone separate from the first dehydrogenation zone; and (e) in the second dehydrogenation zone, dehydrogenating at least a portion of the unreacted C n saturated cyclic hydrocarbons in the presence of a second dehydrogenation catalyst under conditions effective to produce a second dehydrogenation reaction product comprising additional recovered C n aromatic hydrocarbons. (a) contacting a hydroalkylation feed comprising C n aromatic hydrocarbons with hydrogen in the presence of a hydroalkylation catalyst under conditions effective to produce a hydroalkylation reaction effluent comprising (i) C 2n cycloalkylaromatic compounds and (ii) C n saturated cyclic hydrocarbons, wherein n is an integer from 6 to 12; (b) providing at least a portion of the hydroalkylation reaction effluent to a first dehydrogenation zone, therein dehydrogenating at least a portion of the C 2n cycloalkylaromatic compounds and at least a portion of the C n saturated cyclic hydrocarbons in the presence of a first dehydrogenation catalyst under conditions effective to produce a first dehydrogenation reaction product comprising (i) a mixture of C 2n biphenyl compounds; (ii) recovered C n aromatic hydrocarbons; and (iii) unreacted C n saturated cyclic hydrocarbons; (c) separating the first dehydrogenation reaction product into (i) a heavy dehydrogenation stream rich in the C 2n biphenyl compounds, and (ii) a light dehydrogenation stream rich in the recovered C n aromatic hydrocarbons and the unreacted C n saturated cyclic hydrocarbons; (d) providing at least a portion of the light dehydrogenation stream to a second dehydrogenation zone separate from the first dehydrogenation zone; and (e) in the second dehydrogenation zone, dehydrogenating at least a portion of the unreacted C n saturated cyclic hydrocarbons in the presence of a second dehydrogenation catalyst under conditions effective to produce a second dehydrogenation reaction product comprising additional recovered C n aromatic hydrocarbons. <EOS>