Existing Forms And Adsorption Behavior On Ion Exchange Resin Of Mo(Ⅵ) In Acidic Sulfatesolution

Abstract:Existing forms and adsorption behavior on ion exchange resin of Mo(VI) in acidic sulfate solution were systematically studied by ion exchange, infrared spectroscopy and Raman spectra using sodium molybdate solution as the adsorbate. The research shows that Mo(VI) can not be adsorbed by cation exchange but be effectively adorbed by anion exchange resin in sulfate solution with pH0.36～1.24.The experimental results show that D314resin adsorption behavior to molybdenum in sulfate solution with pH0.36～1.24is endothermic and the equilibrium adsorption data are conformed satisfactorily to the Langmuir equation. But the adsorption process is slow and cannot reach equilibrium within24h. The adsorption process is controlled by both the particle diffusion and chemical reaction.The study of Raman spectrum for the solution shows that the existing of sulfate radical in the solution changes the transformation process of molybdate depending on the pH. However the existing of sulfate radical makes the identification of molybdates rather difficult.The IR study of the loaded resin shows that the sulfate radical do not have much influence on the existing forms of molybdenum when the solution pH>2. When the solution pH≤2, the existing of sulfate radical changes the molybdenum forms adsorbed in the resin.The experimental results of combining infrared spectroscopy with Raman spectra shows that the species change of molybdates in the solution without sulfate radical at low pH are:When sulfate radical existing, the species change of molybdates in the solution at low pH are: In acidic sulphate solution system, sulfuric acid and molybdic acid can form heteropolyacid ions, which make the anion exchange resin can effectively adsorb Mo(VI) at low pH.