The removal of organic pollutants from synthetic wash wastewater by a combined multi-phase electro-catalytic oxidation method was evaluated using porous graphite as anode and cathode, and CuO-Co2O3-PO43-modified kaolin as catalyst. The synergic effect on COD removal was studied when integrating the electro-chemical reactor with the effective modified kaolin in a single undivided cell; the results showed that higher COD removal efficiency was obtained than those obtained using the individual processes. Under optimal conditions of pH 3, 30 mA cm(-2) current density, very effective reduction of organic pollutants was achieved with this combined electro-chemical method. High removal efficiency (90%) of the chemical oxygen demand (COD) was obtained in 60 min in the treatment of simulated wash wastewater (anionic surfactant, sodium dodecyl benzene sulfonate [DBS]). This method was also applied to treat wastewater form paper-making and resulted in a COD reduction of 84%. Based on the investigation, a possible mechanism of this combined electro-chemical process was proposed. The pollutants in wastewater could be decreased by the high reactive OH center dot that were produced via the decomposition of electro-generated H2O2 activated by the synergic effect of electro-field and catalyst. The results indicate that the multi-phase catalytic electro-chemical oxidation process is a promising technique for wastewater treatment. (c) 2006 Society of Chemical Industry.