Preparation Ferromanganese Composite Oxides And Hydroxides And The Removal Of Uranium(?) From Aqueous Solution

Iron oxides/hydroxides are widely distributed in soil and sediment,with high specific surface area and high reactive activity,which affect the migration and transformation of many heavy metals and organic pollutants in the environment through adsorption and immobilization.Iron oxides/hydroxides in the environment will bind to a variety of metal ions by adsorption and substitution,thus affecting its physical and chemical properties.The study of manganese substituted iron oxides/hydroxides are concerned by researchers.Therefore,a variety of manganese substituted materials have been successfully synthesized by using iron oxide/hydroxides as the base materials in this paper.The adsorption and immobilization of uranium in the wastewater by different materials was conducted,and the adsorption and immobilization mechanism of uranium were investigated.First,goethite and the Mn-substituted goethite?Mn-Goe10?were synthesized by chemical precipitation methods,the collected solid samples were characterized by XRD?FESEM-EDS?FTIR?BET?Zeta potential.The results indicated that Mn was successfully introduced into the goethite structure,that the surface morphology of goethite changes from flake-like to rod-like,and that the specific surface area of goethite increases fom 24.92 m²/g to 75.22 m²/g,the Zeta potentials of goethite decreases.In this study,the adsorption of uranium?VI?by Mn-Goe10and goethite was investigated as a function of pH,adsorbent dosage,contact time,and initial uranium concentration in batch experiments.The results show that the removal of uranium by Mn-Goe10 can be up to97%when the initial concentration of uranium is 10 mg/L,solution pH=4,dosage of 0.05 g and contact time of 2 h.The uranium?VI?sorption by Mn-Goe10 appeared to be higher than that of goethite.The adsorption process of uranium on Mn-Goe10 and goethite follows the second-order kinetic model and Langmuir model.Jacobsite?MnFe₂O₄?was prepared by chemical precipitation methods and characterized by XRD?SEM?FTIR.The results show that the crystallinity of the sample is good and the morphology of the sample is short rod-like.In this study,the adsorption of uranium?VI?by MnFe₂O₄ was investigated as a function of pH,adsorbent dosage,contact time,and initial uranium concentration in batch experiments.The results show that the removal of uranium by MnFe₂O₄ is 93%when the initial concentration of uranium is 5 mg/L solution pH=6,dosage of0.05 g and contact time of 2 h.The adsorption of uranium on MnFe₂O₄follows the second-order kinetic model and Langmuir model.