Hexavalent chromium removal using ultraviolet photocatalytic reactor

Hexavalant chromium (Cr(VI)) poses an emerging concern in drinking water treatment with stricter regulations on the horizon. Photocatalytic reduction of Cr(VI) was investigated as an engineering scale option to remove hexavalent chromium from drinking or industrial waters via a UV/titanium dioxide (TiO2) process. Using an integrated UV lamp/ceramic membrane system to recirculate TiO2, both hexavalent and total chromium levels were reduced through photocatalytic processes without additional chemicals. Cr(VI) removal increased as a function of higher energy input and TiO2 dosage, achieving above 90% removal for a 1g/L dose of TiO2. Surface analysis of effluent TiO2 confirmed the presence of chromium species.