Liqiud-phase catalytic wet-air oxidation (CWAO) of phenolic compounds is one of the most. prospective methods of waste water purification at high concentrations of toxic phenolic compounds. In this work the synthesis and catalytic properties of mixed platinum-containing nanoparticles stabilized in polymeric matrix of hypercrosslinked polystyrene are discussed. The size of platinum nanoparticles was determined by transmission electron microscopy. Proposed catalytic system showed the high activity, selectivity and stability in the phenol CWAO. The optimal conditions of phenol oxidation leading to the selectivity of 98-99% at 99% conversion were determined and the kinetics of the process at various catalyst loadings, substrate concentrations, and temperatures was studied. Mathematical modelling of the process was carried out allowing the calculation of the reaction network model. (c) 2007 Elsevier B.V. All rights reserved.