Selective separation of lead from aqueous solution with a novel Pb(II) surface ion-imprinted sol-gel sorbent

A novel Pb(II) ion-imprinted mesoporous sorbent (IIMS) was synthesized by a surface imprinting technique combined with a sol-gel process and characterized by FT-IR and N-2 adsorption-desorption. Compared to the non-imprinted mesoporous sorbent (NIMS), the IIMS had a higher adsorption capacity and selectivity for Pb(II). The maximum static adsorption capacities of the IIMS and NIMS for Pb(II) were 221 and 173 mg g(-1), respectively. The relative selectivity coefficients of the sorbent for Pb(II) in the presence of Cd(II), Cu(II) and Zn(II) were 3.7, 1.9 and 3.4, respectively. Furthermore, the IIMS possessed a fast kinetics for Pb(II) sorption from aqueous solution with saturation time of < 20 min, and could be used repeatedly. The detection limit (3 sigma) of this method was 0.23 ng mL(-1) and relative standard deviation of 11 replicate determinations was 3.7 %. The IIMS has been applied to selectively separate and determine Pb(II) in real water samples with satisfactory results.