Advanced oxidation processes: a review of fundamentals and applications in the treatment of urban and industrial wastewaters

Abstract

Contamination of water by toxic and/or recalcitrant species has great environmental impacts. In this context, Advanced Oxidation Processes (AOPs) - technologies that principally use the hydroxyl radical (HO●) for oxidation - have emerged as promising alternatives in treating urban and industrial wastewaters. This study reviewed the literature on POAs and presented data regarding the efficiency of these processes in pollutant degradation, comparing the theoretical reasoning and its industrial applications. The fundamentals and major applications of AOPs (chemical, photochemical, electrochemical, sonochemical and ozone-based processes), as well as their advantages and disadvantages, are described in this review. AOPs have been considered an effective alternative from a technical, economic and environmental viewpoint for the degradation of pollutants in effluents and industrial wastewater, despite having limitations such as high cost of available energy sources, development of new low-cost catalytic materials and construction of full-scale reactors. It is greatly important to the industrial application of AOPs to optimize the effectiveness of these factors.

Keywords:
degradation of pollutants; effluent treatment; hydroxyl radical