Preparation of Pb2+ Double-template Imprinted Sorbent for Selective Separation of Pb2+ from Environmental Water and Sediment Samples

A double-template imprinted sorbent was prepared by a sal-gel imprinting approach for the selective separation of Pb2+ from environmental water and sediment samples. The adsorption property and selective recognition ability of the sorbents were studied by equilibrium-adsorption method. Results showed that in the presence of Cd2+, the selectivity coefficient and the relative selectivity coefficient of the double-template imprinted sorbents for Pb2+ was 91 and 228, respectively, which is much higher than those of CTMAB-imp sorbents (0.4 and 9. 35). The uptake capacities and the selectivity coefficients of the double-template imprinted sorbent were much higher than those of the sorbent prepared without CTMAB template. The extract-ion behavior of the matrix was conformed by Langmuir's equation. Theoretical sorption capacity was 0. 222 mmol/g. Furthermore, the new imprinted sorbent possessed a fast kinetics for the removal of Pb2+ from aqueous solution with the saturation time less than 5 min and could be repeatedly used. This sorbent has been successfully applied to the separation and determination of the trace Pb2+ in standard reference sediment materials and real water samples.