Minimization of organic pollutant content in aqueous solution by means of AOPs: UV- and ozone-based technologies

The study involved comparative investigations of the efficiency of several ozone- and/or UV-based processes: O3, O3/H2O2, UV/H2O2, UV/O3 and UV/H2O2/O3, for the minimization of phenol as a model hazardous pollutant in wastewater. For all applied AOPs the best experimental conditions concerning selected varied process parameters, initial pH and H2O2 dosage, were determined. Different AOPs were evaluated on the basis of their eco-effectiveness, by the means of phenol decay and TOC value decrease, and their cost-effectiveness. It was established that the complete phenol removal can be achieved by adjusting the pH and H2O2 dosage. The overall mineralization extent depended on the type of process, number and type of oxidants and/or UV light, and their studied processes parameters as well. The highest overall mineralization extent, 58.0% TOC removal, was achieved by UV/H2O2/O3 process. From the aspect of both eco- and cost- effectiveness, UV/H2O2/O3 was shown as the most suitable process.