Abstract:Kaolin loaded calcium titanate (KCT) was prepared, and adsorption performance and mechanism of KTC for U(Ⅵ) in radioactive wastewater were studied. Effects of reaction temperature, initial concentration of U(Ⅵ), contact time, and dosage of KCT on adsorption of U(Ⅵ) were investigated. The adsorption kinetics, thermodynamics and adsorption isotherm were conducted. The results show that KCT has a good adsorption capability on U(Ⅵ) in solution. The maximum adsorption rate and adsorption capacity is 94.7% and 197.6 mg/g, respectively under the conditions including pH value of solution of 3.5, dosage of KCT of 0.4 g/L, reaction time of 60 min, and reaction temperature of 25 ℃. The adsorption isotherm, kinetics and thermodynamic studies show that the adsorption of U(Ⅵ) by KCT is a spontaneous and irreversible endothermic reaction process, which conforms to the pseudo-second-order kinetic model and Freundlich isothermal adsorption models, indicating that the adsorption of U(Ⅵ) is a process of coexistence of physical and chemical adsorption, and is dominated by heterogeneous adsorption.