| Summary: | The objective of this work was to study the suitability of catalytic wet air oxidation (CWAO) for the treatment of olive mill wastewater (OMW). Accordingly, experiments were performed in a high pressure reactor at 100ºC and 200ºC under an oxygen partial pressure of 6.9 bar, using carbon supported platinum (1wt.% Pt) and iridium (5 wt.% Ir) catalysts prepared by incipient wetness impregnation. Both catalytic systems showed a very high activity in the total organic carbon (TOC) removal of the effluent, an increase in TOC removal relatively to non-CWAO being observed. At 200ºC, complete TOC and colour removal was obtained with the Pt/C catalyst after 8 h of reaction. At 100ºC, the results indicate that a certain fraction of compounds in the effluent (low molecular weight recalcitrant carboxylic acids)could not be removed even after prolonged reaction time. A kinetic model was developed taking into account catalytic and noncatalytic reaction, formation of refractory compounds and catalyst deactivation. A very good agreement between the model results and the CWAO experimental data at 200ºC was found. The results obtained in this work indicate that Pt/C is a promising catalyst for the CWAO of OMW.
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