ALUMINA-SUPPORTED NOBLE-METAL CATALYSTS FOR DESTRUCTIVE OXIDATION OF ORGANIC POLLUTANTS IN EFFLUENT FROM A SOFTWOOD KRAFT PULP-MILL

The effectiveness of alumina-supported noble metal catalysts for the d estructive oxidation of organic pollutants in effluent from a softwood kraft pulp mill was evaluated in a slurry reactor at 463 K and an oxy gen pressure of 1.5 MPa. The effects of catalyst preparation procedure s, such as metal loading, calcination, or reduction treatment on the c atalytic activities, were also tested. Alumina-supported palladium cat alysts were found to be more effective than supported manganese, iron, or platinum catalysts. The rate of oxidation over Pd/alumina catalyst was significantly higher than that of the uncatalyzed reaction. Addin g Ce on the alumina support was found to promote the activity of alumi na-supported Pt catalyst but inhibit the activity of alumina-supported Pd catalyst. The reaction mechanisms for the catalytic wet oxidation process and the roles of Ce on catalytic activity for destructive oxid ation of organic pollutants in wastewater are discussed.