Economic feasibility of arsenic removal using nanofiltration membrane: A mini review

Abstract

Arsenic contamination in drinking water causes serious environmental and health issues worldwide. More than 230 million people are exposed to arsenic contamination. Among these, 78% of this exposure are reported in south Asian developing countries and water crisis is already an existing issue. Due to environmental and health issues of arsenic exposure, World Health Organization recommends the maximum contaminant limit for arsenic in drinking water to be 0.01 mg/L. It emerges the need to find out cost-effective treatment that can comply with stringent environmental standards. The available methods to remove arsenic are chemical precipitation, adsorption, ion exchange process and pressure-driven membrane techniques. Among these, high-pressure-driven membrane separation processes such as reverse osmosis and nanofiltration are the promising method that can provide the recommended drinking water quality. Nanofiltration consumes less energy than reverse osmosis as the latter requires a higher transmembrane pressure. The aim of this paper is to review arsenic exposure worldwide, aqueous chemistry, occurrence, health issues and available techniques for its removal. Economic feasibility of nanofiltration membrane for arsenic removal is also discussed.