Ultrasound-assisted enhanced electroxidation for mineralization of persistent organic pollutants: A review of electrodes, reactor configurations and kinetics

Abstract

Discharge of toxic and hazardous pollutants in the aquatic bodies is dangerous for the human being and aquatic life. Nowadays, novel methods need to be developed to increase the treatment efficiency of such types of pollutants. Among the electrochemical technologies, electroxidation coupled with power ultrasound, so-called sonoelectroxidation, has gained attention because of its ability to remove a wide range of ubiquitous pollutants. The use of power ultrasound, in combination with electroxidation, provides the synergistic effect by virtue of chemical and physical effect of ultrasound for degradation of compounds. This review presents a critical analysis of studies (1996–2020) on the treatment of various synthetic and real wastewater using the sonoelectroxidation process. An overview of current advancement in electrode material and reactor geometry has been deliberated. Coupling these two techniques increased the mineralization degree in a remarkable way. This review critically evaluates various types (batch and continuous) of sonoelectro reactors used in the sonoelectrochemical process. Kinetics of the degradation process has been reviewed in detail. Challenges associated with these technologies and sluggish development in reactor geometries have been identified with the foremost application in wastewater treatment. © 2020 Taylor & Francis Group, LLC.