Removal of Cr VI ions and Malachite green dye from aqueous media using TiO2 Fly ash nanocomposite

Abstract

The scarcity of pure water is a major problem of our country. Most newlineof us consume contaminated water for various purposes. As human needs newlineare increasing day by day and, the industries are born and grown, the newlineproblem of wastewater discharge has become more and more severe. Textile newlineindustries are the primary source that release synthetic dyes to the newlineenvironment. Process waste streams like mining, electroplating, iron and newlinesteel industries, metal plating etc. contain heavy metal concentration newlineexceeding the discharge limit. These streams contain chromium, nickel, newlinecadmium copper etc. Chromium is dominant in most of the effluent streams newlinecompared to other metal ions. The present study explores the possibility of newlineusing a nano composite of titanium dioxide (TiO2) and chemically treated newlinefly ash(CFA) as adsorbent to remove hexavalent chromium ions from waste newlinewater. Fly ash is an industrial waste generated in power plants and its good newlineadsorption properties makes the system cost effective. TiO2is proved to be newlineefficient material for waste water treatment due to its excellent photo newlinecatalytic properties. By making a nanocomposite of fly ash and TiO2, the newlinerate and efficiency of removal of chromium ions can be increased by newlineutilizing the high surface area at a reduced cost. TiO2-Flyash nanocomposite had been successfully synthesized via newlinethermal hydrolysis process at 1200Cand 48h.continuous reflux condensation. newlineThe product was characterized by XRD, SEM and FTIR spectroscopy and newlineused to adsorb Cr(VI) ions from aqueous media as well as to explore the newlinepossibility for photo catalysis to remove malachite green dye from water. newlineBatch experiments were conducted for adsorption and photo catalytic newlinedegradation. The results of XRD and SEM demonstrated that the as newlineprepared product was mainly TiO2 CFA nanoparticles having large surface newlinearea. newline