Process for preparing dialkyl 1,4-cyclohexanedicarboxylates

A process for preparing dialkyl 1,4-cyclohexanedicarboxylate in which the two alkyl groups both have at least 2 carbon atoms, the process comprising:

• carrying out a ring hydrogenation of a dialkyl terephthalate in which the two alkyl groups both have at least 2 carbon atoms, in the presence of a heterogeneous hydrogenation catalyst, with a hydrogen-containing gas, to form the dialkyl 1,4-cyclohexanedicarboxylate,
• wherein the dialkyl terephthalate in the ring hydrogenation has a CO value of less than 0.3 mg KOH/g.