Two wet-proofed catalysts were prepared by subsequent coating steps with polytetrafluoroethylene fibers over a CuO/γ Al2O3 catalyst. They were tested for the oxidation of phenol solutions in a semi-batch reactor. Phenol conversion as well as Chemical Oxygen Demand (COD) was recorded. The hydrophobic coverage reduces the loss of active phase by leaching. Therefore, deactivation was attributed to the deposition of carbonaceous residues on the catalytic surface.