1. A PROCESS FOR THE HYDROGENATION OF A COMPOUND OF THE GROUP CONSISTING OF HYDROXY-SUBSTITUTED AROMATIC HYDROCARBONS, ALKOXY-SUBSTITUTED AROMATIC HYDROCARBONS, POLYHYDROXY-SUBSTITUTED AROMATIC HYDROCARBONS AND POLYALKOXY-SUBSTITUTED AROMATIC HYDROCARBONS, WHICH COMPRISES ADMIXING THE COMPOUND AND AN AQUEOUS ALKALINE SOLUTION DILUENT HAVING AN ALKALI CONCENTRATION OF AT LEAST ABOUT .0001 M, AND TREATING THE RESULTING ADMIXTURE WITH HYDROGEN AT A REACTION TEMPERATURE AND JPRESSURE IN THE PRESENCE OF A RUTHENIUM-CONTAINING CATALYST WHEREBY THE HYDROGENATION IS EFFECTED WITHOUT DETECTABLE HYDROGENOLYSIS OCCURRING.