Document Type

Original Study


In this study, an investigation of the catalytic ozonation of pentachlorophenol (PCP) in the presence of aluminum oxide (Al2O3) and the formation of byproducts during the ozonation has been done. From the results, it is clear that catalytic ozonation in the presence of Al2O3 can substantially enhance the efficiency of the PCP degradation to a higher degree than when the ozonation process alone is used. Several environmental parameters, including the pH of the solution, initial PCP concentration, Al2O3 dosage and dissolved ozone concentration were also investigated in terms of their influence. The highest efficiency of PCP degradation (100% degradation) was achieved under the conditions mentioned, namely, pH 8, 1.87 g/LAl2O3, and 0.49 g/L dissolved ozone concentration. Further, the role played by the catalyst used was demonstrated. The catalytic action of the Al2O3was linked to a highly hydroxylated surface. The surface hydroxyl groups on the Al2O3were, in fact, the active sites during catalytic ozonation. According to the drastic changes in the solution color observed during ozonation in this study and from the results of some earlier researches, the formation of intermediate reaction products during ozonation was verified. The free chloride ions released, especially when the solution was slightly alkaline, was also studied in the catalytic ozonation process.