Reduction of Cr(VI) to Cr(III) from Photovoltaic Waste-Water

Abstract

The objective of this study is the use of two photocatalysts based on metal oxides which are titanium dioxide (TiO2) and zinc oxide (ZnO) to reduce hexavalent chromium Cr(VI) which is a photovoltaic industry pollutant to trivalent chromium Cr(III) in the UV field. The effects of various parameters such as pH, the amount of the catalyst, the concentration of the pollutant and the volume of hydrogen peroxide (H2O2) are discussed. As a final test, we used sunlight instead of the UV lamp. It was found that the catalytic process exhibited the highest photocatalytic activity using TiO2 anatase than ZnO under the same operating conditions, so the reduction rates are higher with titanium oxide than with zinc oxide....