Electrochemical Abatement of Hydrogen Sulfide from Waste Streams

Hydrogen sulfide is ubiquitously present in many waste streams originating from industrial activities as well as in sewage. It needs to be removed as it is toxic, corrosive, and odorous. Conventional abatement strategies involve physicochemical methods, which require significant amounts of chemicals and/or high energy input. Considering the limitations of physicochemical methods, there is a need for more cost-effective and sustainable abatement strategies. Recent advances in electrode materials and operation have stimulated interest in electrochemical methods for pollutant remediation. Several electrochemical approaches for sulfide abatement have been proposed over the last few years. Electrochemical techniques offer several advantages including the avoidance of dosage, handling, transport and storage of potentially hazardous chemicals, and the possibility of recovering sulfide or sulfur from wastewater as a product. This paper reviews electrochemical strategies that have been proposed for removal of dissolved and gaseous hydrogen sulfide. The advantages and disadvantages as well as the economic potential of each of the proposed methods are discussed. The technical aspects and key challenges to enable full-scale implementation are highlighted. Finally, opportunities for expanding electrochemical methods for sulfide abatement are presented.