Photochemical removal of hexavalent chromium and nitrate from ion-exchange brine waste using carbon-centered radicals

Ion-exchange (IX) is a promising technology to remove hexavalent chromium Cr(VI) and nitrate from groundwater; however, its wide application is challenged by a costly disposal of spent brine. This study developed a novel photochemical process utilizing reductive carbon-centered radicals to remove Cr(VI) and nitrate in IX spent brine. In the presence of formate or alcohol additives, photolysis of nitrate in spent brine generated highly reductive...