Environment Protection Engineering · 2012 · 54 citations · 0 references
Natural SciencesChemical EngineeringChemistryCatalysisWastewater TreatmentWater TreatmentChemical ReductionOxidation-reduction ReactionsPhotocatalysisPhotochemical KineticsPhotochemistryRedox CatalysisFirst-order KineticsMetal Oxide Nanomaterials For Environmental RemediationPhotocatalysis By Metal Oxide NanomaterialsPhotocatalytic OxidationPhotocatalytic ReductionPhotocatalytic TreatmentPhotocatalytic Water TreatmentZinc Oxide Photocatalysis
Photocatalytic reduction of Cr(VI) to Cr(III) in aqueous solutions under UV irradiation and ZnO semiconductor catalyst was investigated using potassium dichromate as a model compound. The effects of pH, catalyst dose (0.05-0.15 g/dm 3 ), Cr(VI) initial concentration (0.1-15 mg/dm 3 ) and hydrogen peroxide concentration on photocatalytic reduction of Cr(VI) were investigated. The reduction rate of chromium was more favorable in acidic solution. Hydrogen peroxide was added as a reduction reagent for enhancement of the photoreduction. The process of photoreduction of Cr(VI) approximately followed first-order kinetics. Drinking water samples and wastewater were collected and photocatalytically treated for reduction of Cr(VI). 2 4 2 7 (HCrO and Cr O ).