Visible light induced photocatalytic reduction of metals (Cr, Cu, Ni, and Zn) and its synergism with different pH, TiO2, and H2O2 doses in simulated wastewater

Abstract

An attempt has been made to treat the wastewater containing a combination of inorganic contaminants to take the advantage of solar photocatalytic redox reactions. Synthetic wastewater is prepared containing substantial heavy metals to obtain a simultaneous reduction of both the wastewater components. The reaction is also attempted at different pH values to optimize the same. The metals in the waste combination are Cr, Ni, Zn, and Cu. Dark adsorption reactions are also performed along with the sunlight irradiation, in order to understand the process in detail. Results show that significant chromium and copper are the metals which are significantly reduced as compared to the other two metals studied. Chromium showed maximum reduced in the acidic pH range whereas the other metals were reduced in the alkaline and neutral pH ranges. The results provide a cost-effective method to remove organic and inorganic pollutants simultaneously in the simulated wastewater through photocatalytic. V C 2013 AIP Publishing LLC. [http://dx.

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