Physio-chemical treatment technologies for chromium removal

Abstract

Abstract. The article reviews the technical applicability of various physio-chemical treatments for the removal of hexavalent chromium (Cr(VI)) from aqueous solution. A particular focus is given to membrane electrolysis, photocatalytic reduction, adsorption and the application of nanotechnology in Cr(VI) removal. About 50 published studies (2011)(2012)(2013)(2014)(2015)(2016)(2017) are reviewed. Liquid membrane and electrodialysis were combined. Metal-organic frameworks (MOFs) emerged to enhance photocatalytic reduction. It is evident that adsorption is the most frequently studied and widely applied for the treatment of Cr(VI). And nanotechnology is mainly applied to nanoadsorbent which exhibited both reduction and adsorption capabilities. In general, further researches on methods with cost-effectiveness, technical-applicability, and plant-simplicity are vital for heavy metal removal such as chromium.