Intermediary Compounds in Advanced Oxidation Processes for Wastewater Treatment

Abstract

The research on advanced oxidation processes, like heterogeneous and homogeneous photo-catalysis, increased considerably in the last decade, due to their successful application in removing wastewater pollutants. During these photo-catalytic processes, complex chain reactions occur that may lead to the formation of intermediates (radicals), some even more hazardous than the initial ones. The aim of the advanced oxidation processes is to achieve the total mineralization of the pollutant, which implies process control. This paper gives a basic review of the last research done on the degradation products formed during dyes photo-degradation and their control, in aqueous solutions under visible or UV irradiation.