New Trends in Electrocoagulation for the Removal of Dyes from Wastewater: A Review

Electrocoagulation (EC) is a powerful and environmentally friendly technology for the treatment of azo dyes, acid, and reactive dyes. This article reviews the fundamental and recent developments in EC and EC-coupled processes for the removal of dye from wastewater. EC processes utilize different electrolytic reactors, such as batch reactor, continuous reactor, and electrodes of monopolar and bipolar configurations. Different cathodes and anodes used in this process are discussed and the mechanisms are reviewed. Effects of various operating parameters like pH, the nature of electrolytes, electrolyte concentration, initial concentration of dye, current density, exposed area of electrodes, spacing of electrodes, temperature of solution, electrode configuration, and number of electrodes and their optimum ranges for dye removal are reviewed. Kinetic models and their reaction rate constants for different dyes are analyzed. Different dye pollutants removed by this process and their degradation are also reported.