Ozonation enhancement by Fe-Cu bimetallic particles

Abstract

The aim of this work was to assess the effect of the bimetallic system Fe–Cu on the ozonation efficiency of indigo carmine and its main degradation product, isatin-5-sulfonic acid. As reference, experiments with single metal particles were also conducted. The metallic systems were synthesized by a chemical reduc- tion method and characterized by EPR and HR-SEM/EDS. Cu and Fe oxidation states were found to be 2 + . The ozonation process was carried out in an up-flow bubble column. The organic compounds concentra- tion was determined by UV–vis spectroscopy. The degree of oxidation and mineralization was determined by COD and TOC measurements, respectively. The effect of pH was also studied. It was found that the use of the bimetallic system not only considerably (by three times) improves the ozonation rate but also the mineralization degree of indigo carmine. The best results (97% indigo carmine removal and 92% of TOC removal) were obtained at pH 3 and with 10 0 0 mg/l of Fe/Cu particles.