Adsorption Characteristic of U(Ⅵ) on Illite in Aqueous Environment

Taking illite as adsorbent, the adsorption characteristics of U(Ⅵ) on illite were investigated through static adsorption experiments. The effects of contact time, adsorbent quality, initial concentration of U(Ⅵ), pH and temperature on adsorption were investigated respectively. FT-IR and SEM were used to characterize illite before and after adsorption, and the kinetics and thermodynamics of U(Ⅵ) adsorption on illite were investigated. The results show that the adsorption process reaches dynamic equilibrium after 10 h. When the initial concentration of U(Ⅵ) is 50 mg/L, the adsorption effect is the best. The best adsorbent dosage is 0.03 g. pH has a significant effect on the adsorption of uranium on illite, and the optimal pH is 5.6. Increasing temperature is beneficial to the adsorption of U(Ⅵ) on illite. Quasi-second-order kinetic model and Langmuir isothermal adsorption model have good fitting effect on the adsorption process of U(Ⅵ) on illite. The adsorption process is mainly surface complexation, belonging to single-layer adsorption.