Combined electrocoagulation processes as a novel approach for enhanced pollutants removal: A state-of-the-art review

Zakaria Al-Qodah; Muhammad Tawalbeh; Mohammad Al-Shannag; Zaid Al-Anber; Khalid Bani-Melhem

doi:10.1016/j.scitotenv.2020.140806

Combined electrocoagulation processes as a novel approach for enhanced pollutants removal: A state-of-the-art review

Sci Total Environ. 2020 Nov 20:744:140806. doi: 10.1016/j.scitotenv.2020.140806. Epub 2020 Jul 12.

Authors

Zakaria Al-Qodah¹, Muhammad Tawalbeh², Mohammad Al-Shannag³, Zaid Al-Anber¹, Khalid Bani-Melhem⁴

Affiliations

¹ Chemical Engineering Department, Al-Balqa Applied University, 11134 Amman, Jordan.
² Sustainable and Renewable Energy Engineering Department, University of Sharjah, Sharjah, United Arab Emirates. Electronic address: mtawalbeh@sharjah.ac.ae.
³ Department of Chemical Engineering, School of Engineering, The University of Jordan, 11942 Amman, Jordan; Jordan Uranium Mining Company, 11953 Amman, Jordan. Electronic address: m.shannag@ju.edu.jo.
⁴ Department of Water Management and Environment, Faculty of Natural Resources and Environment, The Hashemite University, Al-Zarqa, Jordan.

PMID: 32717462
DOI: 10.1016/j.scitotenv.2020.140806

Abstract

A novel approach using the integration of electrocoagulation, with one or more treatment processes has been recently practiced to improve the removal of colloidal and non-biodegradable pollutants. Several treatment processes including adsorption, chemical coagulation, magnetic field, reverse osmosis, and membrane filtration have been combined with electrocoagulation treatment step to improve pollutants removal efficiency. These combined systems showed the potential to improve the performance of the treatment process. This paper presents a state-of-the-art review for the recent processes available in the literature that combine treatment electrocoagulation with one of the previously mentioned treatment processes. It is found that the removal efficiency of any combined processes is higher than that of any single treatment process and the combined process has up to 20% higher removal efficiency compared to electrocoagulation alone. However, most reported studies were conducted at bench-scale level with synthetic wastewater instead of real wastewater. The main aspects of these combined systems including process mechanism, kinetic models, cost and the scale up of combined processes were discussed and summarized. Finally, several concluding remarks were drawn in view of the literature investigations and the gaps that suggest more studies and insights for future development were addressed.

Keywords: Adsorption; Chemical coagulation; Combined treatment processes; Electrocoagulation; Magnetic field; Reverse osmosis-assisted electrocoagulation.