A process for making cyclohexanone, the process comprising: feeding hydrogen and a hydrogenation feed into a hydrogenation reaction zone, the hydrogenation feed comprising, based on the total weight of the hydrogenation feed: phenol at a concentration in a range from 10 wt% to 99 wt%; cyclohexanone at a concentration in a range from 0.1 wt% to 50 wt%; cyclohexylbenzene at a concentration in a range from 0.001 wt% to 30 wt%; and bicyclohexane at a concentration in a range from 0.001 wt% to 30 wt%; and contacting at least a portion of the phenol with at least a portion of the hydrogen in the hydrogenation reaction zone in the presence of a hydrogenation catalyst under hydrogenation reaction conditions such that at least a portion of the phenol is converted to cyclohexanone, wherein the hydrogenation reaction conditions comprise a temperature in a range from 140°C to 300°C and an absolute pressure in a range from 375 kPa to 1200 kPa, such that in the hydrogenation reaction zone at least one of the following conditions is met: (i) at least 50% of the cyclohexylbenzene is present in liquid phase; and (ii) at least 50% of the phenol is present in liquid phase, wherein in step, the hydrogenation reaction zone comprises a tubular heat exchanger reactor comprising a plurality of tubes and a shell enclosing the tubes, at least a portion of the hydrogenation catalyst is located inside the tubes, and step comprises: passing a mixture comprising hydrogen and phenol from the hydrogenation feed through the tubes in contact with the hydrogenation catalyst; and passing a cooling medium through the shell, thereby cooling the reaction mixture inside the tubes. feeding hydrogen and a hydrogenation feed into a hydrogenation reaction zone, the hydrogenation feed comprising, based on the total weight of the hydrogenation feed: phenol at a concentration in a range from 10 wt% to 99 wt%; cyclohexanone at a concentration in a range from 0.1 wt% to 50 wt%; cyclohexylbenzene at a concentration in a range from 0.001 wt% to 30 wt%; and bicyclohexane at a concentration in a range from 0.001 wt% to 30 wt%; and phenol at a concentration in a range from 10 wt% to 99 wt%; cyclohexanone at a concentration in a range from 0.1 wt% to 50 wt%; cyclohexylbenzene at a concentration in a range from 0.001 wt% to 30 wt%; and bicyclohexane at a concentration in a range from 0.001 wt% to 30 wt%; and contacting at least a portion of the phenol with at least a portion of the hydrogen in the hydrogenation reaction zone in the presence of a hydrogenation catalyst under hydrogenation reaction conditions such that at least a portion of the phenol is converted to cyclohexanone, wherein the hydrogenation reaction conditions comprise a temperature in a range from 140°C to 300°C and an absolute pressure in a range from 375 kPa to 1200 kPa, such that in the hydrogenation reaction zone at least one of the following conditions is met: (i) at least 50% of the cyclohexylbenzene is present in liquid phase; and (ii) at least 50% of the phenol is present in liquid phase, wherein in step, the hydrogenation reaction zone comprises a tubular heat exchanger reactor comprising a plurality of tubes and a shell enclosing the tubes, at least a portion of the hydrogenation catalyst is located inside the tubes, and step comprises: passing a mixture comprising hydrogen and phenol from the hydrogenation feed through the tubes in contact with the hydrogenation catalyst; and passing a cooling medium through the shell, thereby cooling the reaction mixture inside the tubes. (i) at least 50% of the cyclohexylbenzene is present in liquid phase; and (ii) at least 50% of the phenol is present in liquid phase, wherein in step, the hydrogenation reaction zone comprises a tubular heat exchanger reactor comprising a plurality of tubes and a shell enclosing the tubes, at least a portion of the hydrogenation catalyst is located inside the tubes, and step comprises: passing a mixture comprising hydrogen and phenol from the hydrogenation feed through the tubes in contact with the hydrogenation catalyst; and passing a cooling medium through the shell, thereby cooling the reaction mixture inside the tubes. passing a mixture comprising hydrogen and phenol from the hydrogenation feed through the tubes in contact with the hydrogenation catalyst; and passing a cooling medium through the shell, thereby cooling the reaction mixture inside the tubes.