Electrochemical methods for the removal of anionic contaminants from water – A review

•Different electrochemical methods for anionic pollutants have been reviewed.•Electrocoagulation, electrooxidation, and electroreduction methods are reviewed.•Optimum conditions for anions removal by electrochemical methods are discussed. Different electrochemical methods such as electrocoagulation, electro-oxidation, and electroreduction have been found effective for the removal of various anionic pollutants from water and wastewater. Electrochemical processes can transform contaminants directly or manipulate the redox condition of the environmental matrix to achieve adaptive condition. This review focuses on the removal of different anions, including cyanide, fluoride, nitrate, nitrite, phosphate, and sulfate, from water by electrocoagulation, electro-oxidation, and electroreduction methods. Optimum treatment conditions for studied anions in each electrochemical method are discussed. An overview of electrochemical methods used for anions removal together with specific applications and experimental results are presented and discussed. It is evident from the literature reviewed that these methods have shown considerable potential for the removal of anionic pollutants from water. However, the most challenging issue in this research area is to find out the practical application of these methods on commercial scale, leading to the improvement of pollution control.