A process for the construction of a second chemical plant, which second chemical plant is suitable for the separation of cyclohexanone from a second mixture, which second mixture comprises reaction products from the hydrogenation of phenol, said process comprising: a) providing a first chemical plant, which first chemical plant is suitable for the separation of cyclohexanone from a first mixture, which first mixture comprises reaction products from the oxidation of cyclohexane, and which first plant comprises: i) a distillation column suitable for distilling overhead cyclohexane; ii) a distillation column suitable for distilling overhead cyclohexanone; iii) a distillation column suitable for distilling overhead components having a lower boiling point that cyclohexanone; iv) a distillation column suitable for distilling overhead a mixture comprising cyclohexanol and cyclohexanone; v) a cyclohexane oxidation unit suitable for the oxidation of cyclohexane; and vi) a heat recovery unit suitable for the recovery of heat from off-gas from the cyclohexane oxidation unit suitable for the oxidation of cyclohexane; b) disabling i) said distillation column suitable for distilling overhead cyclohexane from said first chemical plant, v) said cyclohexane oxidation unit and vi) said heat recovery unit, and wherein said second chemical plant comprises a distillation column suitable for distilling overhead cyclohexanone, wherein said cyclohexanone is part of a third mixture, which third mixture comprises said second mixture from which components having a lower boiling point than cyclohexanone have been removed; and c) adding to said first chemical plant a phenol hydrogenation unit. a) providing a first chemical plant, which first chemical plant is suitable for the separation of cyclohexanone from a first mixture, which first mixture comprises reaction products from the oxidation of cyclohexane, and which first plant comprises: i) a distillation column suitable for distilling overhead cyclohexane; ii) a distillation column suitable for distilling overhead cyclohexanone; iii) a distillation column suitable for distilling overhead components having a lower boiling point that cyclohexanone; iv) a distillation column suitable for distilling overhead a mixture comprising cyclohexanol and cyclohexanone; v) a cyclohexane oxidation unit suitable for the oxidation of cyclohexane; and vi) a heat recovery unit suitable for the recovery of heat from off-gas from the cyclohexane oxidation unit suitable for the oxidation of cyclohexane; i) a distillation column suitable for distilling overhead cyclohexane; ii) a distillation column suitable for distilling overhead cyclohexanone; iii) a distillation column suitable for distilling overhead components having a lower boiling point that cyclohexanone; iv) a distillation column suitable for distilling overhead a mixture comprising cyclohexanol and cyclohexanone; v) a cyclohexane oxidation unit suitable for the oxidation of cyclohexane; and vi) a heat recovery unit suitable for the recovery of heat from off-gas from the cyclohexane oxidation unit suitable for the oxidation of cyclohexane; b) disabling i) said distillation column suitable for distilling overhead cyclohexane from said first chemical plant, v) said cyclohexane oxidation unit and vi) said heat recovery unit, and wherein said second chemical plant comprises a distillation column suitable for distilling overhead cyclohexanone, wherein said cyclohexanone is part of a third mixture, which third mixture comprises said second mixture from which components having a lower boiling point than cyclohexanone have been removed; and c) adding to said first chemical plant a phenol hydrogenation unit.