Reactivity of various Ru/CeO2 catalysts during ozonation of succinic acid aqueous solutions

Ozonation of aqueous solutions of succinic acid ([SA](o) = 1 mM) was studie d in the presence of ruthenium (2%) deposited on cerium dioxide catalysts. The influence of ruthenium, of the catalyst preparation mode (impregnation or exchange), of the support pretreatment, of the surface area and of the f inal treatment of the catalyst (by calcination or reduction) has been exami ned. Under our experimental conditions, the acid was not removed by ozone a lone and its adsorption on the catalytic material was limited (<120 mu mol L-1). The presence of ruthenium was necessary for the observation of a cata lytic activity of the cerium dioxide material. The best activity and minera lization are observed for the catalysts prepared by impregnation. Among the exchanged catalysts, the preparation using a basic exchange induces only a weak activity. Pretreatment of the support does not influence the catalyti c properties whereas after Ru deposit, a final treatment by reduction is pr eferable to calcination. Such catalysts could be optimized in the future fo r their use in the held of wastewater depollution or even drinking water tr eatment.