Catalytic wet air oxidation for the abatement of phenol solutions using novel wet proofed CuO/Al2O3 catalysts

P. MASSA; F. IVORRA; P. HAURE; R. FENOGLIO

Madrid, España

Simposio; International Symposium on "Catalysis for Clean Energy and Sustainable Chemistry" CCESC; 2008

Considering the need for environmental protection, one of the promising options for removal of toxic and non-biodegradable organic compounds from industrial wastewaters is destruction of these contaminants by Catalytic Wet Air Oxidation (CWAO). Most of the catalytic systems used in CWAO of organic solutions are based on metal oxides that show good activity, but serious stability problems [1-3]. In fact, two combined effects are the main responsible of catalyst deactivation: the lixiviation of the metallic ions in the hot acidic reaction medium and the formation of carbonaceous deposits onto the active sites [3]. To minimize the deactivation/lixiviation processes, we proposed to cover conventional CuO/Al2O3 catalysts with a polytetrafluorethylene (PTFE) layer [2, 4]. The presence of this hydrophobic film would reduce the direct contact of the active phase with the aqueous reaction medium, allowing the reactants to diffuse and react into the catalyst. The objective of this work is to optimize the catalyst-PTFE impregnation procedure in order to obtain a complete, thin and homogeneous coverage. Conventional and wet-proofed CuO/g-Al2O3 catalysts were tested for the CWAO of phenol in a laboratory Trickle Bed Reactor (TBR) operated at 140°C and 7 atm of oxygen.