Amino functionalized mesoporous silica gel was synthesized, characterized and used as adsorbents for low concentration of Mn2+ and Co2+ simulating the 60Co2+ and 56Mn2+ in low-level radioactive wastewater. The adsorption capacities with different contact time and at pH were calculated. Three adsorption isotherms were employed, and the Sips model described the adsorption best, the maximum adsorption capacities for Co2+ and Mn2+ calculated by this model were 0.377mmol/g and 0.384mmol/g respectively. The competitive experiments showed that the affinity between adsorbents and metal ions is different. The adsorbents retained Co2+ much easier. Dynamic adsorption experiments were carried out in a fixed bed column which suffered a decrease of adsorption capacity than statistic experiments.
