Hydrogenation of phenol

The catalytic hydrogenation of phenol obtained by the cumene hydroperoxide process is improved by hydrogenating high purity phenol containing not more than 75 ppm of acetol, an impurity found in phenol prepared from cumene. Acetol-free phenol is obtained by treating phenol for 1-5 minutes with a polyamine such as hexamethylene diamine, hexamethylene triamine and the like or an aqueous solution thereof, and then distilling the mixture to separate the components. Alternatively, the hydrogenability of phenol can be improved by injecting the polyamine into the reaction mixture during hydrogenation.