Synthesis, Characterization and Adsorption Behavior of Cd(II) Ion-Imprinted Mesoporous Materials

Cd(II) ion-imprinted mesoporous (IIM) materials were synthesized using surface imprinting technique. The materials were characterized by TEM, FTIR, XRD and the adsorption behavior of the materials towards Cd(II) in aqueous solution was studied. The results show that the material has a typical mesoporous structure with the average pore size of 6.23 nm. The batch adsorption experiments were performed using the prepared ionic imprinted mesoporous material as absorbent. The effects of adsorption time, temperature and pH on the adsorption capacity were investigated. Additionally, the thermodynamics and kinetics analyses were also carried out. The results demonstrate that the adsorption capacity is 49.6 mg · g^–1 when the adsorption time is 1 h, the temperature is 25 °C and pH is 7.0. The removal efficiency can exceed 80%. The adsorption is a spontaneous, exothermic and entropy decrease process based on the results of adsorption thermodynamics. The obtained ionic imprinted mesoporous material possesses high adsorption capacity towards Cd(II) and can be reused.