Chapter 4 - Electrochemical reduction of heavy metals from industrial effluents

Abstract

Heavy metals are the most widely used chemical catalysts for a broad spectrum of industries, including steel making, electronics, batteries, and leather tanning. These industries are exonerating this toxic heavy metal-containing wastewater as industrial effluents into the surrounding environment, which ultimately alters environmental biodiversity and influences community health. Therefore, environmental and human safeties need to be a foremost priority to procure at present. In this aspect, electrochemical reduction is one of the most efficient processes to minimize toxic heavy metal contamination in industrial effluent before it is disposed of. Environmental compatibility, higher efficacy, and higher cost-effectiveness make the electrochemical reduction process for heavy metal remediation an attractive and industrially feasible technology. Electrochemical reduction of toxic heavy metals involves distinct segments such as electrodeposition, electrosorption, electrodialysis, electrodeionization, bioelectrochemical reduction, and photoelectrochemical reduction. However, the current state of the electrochemical reduction approach has several drawbacks, including concentration polarization from dilute metal ions, dendrite and spongy deposit formation, sluggish metal ion transportation kinetics, and salvage reactions from the hydrogen development and oxygen reduction networks. To this end, the current extensive literature review deals with deep insight into the current advances in electrochemical reduction of toxic heavy metals to ameliorate the potentiality of electrochemical process performances upon heavy metal remediation and recovery from industrial effluents in the near future.