A photovoltaic powered ocean-based electrochemical system produces highly oxidizing active substances for simultaneous removal of antibiotics and heavy metals from mariculture wastewater

Abstract

Mariculture wastewater contains a diverse array of pollutants, such as antibiotics, heavy metals, and ammonia nitrogen (${\text{NH}}_4^{+}$-N). The concurrent removal of multiple pollutants has emerged as an urgent problem that demands immediate attention. In this research, photovoltaic powered ocean-based electrochemical system (POECs) was employed to treat mariculture wastewater. POECs exhibited outstanding performance in the treatment of mariculture wastewater, attaining high removal rates for various pollutants: 98 % for TC, 97.4 % for Cu(II), and 95.5 % for ${\text{NH}}_4^{+}$-N. The integration of the bioelectrochemical system (BES) and the electrolytic cell (EC) augmented the overall treatment capacity of the system. This integration led to the generation of a variety of highly oxidizing active species, including hydroxyl radicals and reactive chlorine species (RCS). In the anode chamber, the ocean - sourced sludge served as a source of bioelectricity. At the class level, functional microorganisms like Gammaproteobacteria and Campylobacteria were the dominant species. The study offers technical optimization for the environmentally-friendly treatment of mariculture wastewater and holds promising prospects for engineering applications.