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A novel adsorbent was prepared by grafted the Dibenzo-18-Crown-6-Ether (DB18C6) on D564 resins and characterized by Thermogravimetry (TG) and Fourier Transform Infrared Spectroscopy (FTIR). Adsorption of Sr 2+ from aqueous solutions was investigated in batch method as a function of contact time, concentration of Sr 2+ and pH of the solution. It is found that the adsorbent has good selectivity for Sr 2+. The efficient adsorption of Sr 2+ is obtained at pH 5-6 before adsorption or pH 7-8 after adsorption. And the adsorption amount increases with the Sr 2+ concentration and decreases with the temperature of the solution.

Several different Li + -imprinted gels were prepared by different precursors. And the gels were characterized by textual properties and point of zero charges (PZCs). The adsorption of Li + from their aqueous solutions by the gels was investigated. The surface areas of the gels were found to range from 60 to 633 m 2 /g depending on the gel composition. In general, most of the gels are microporous with a pore size smaller than 2 nm. The gels have PZCs ranging from 1.25 to 3.20 after acidification with HCl solution. The adsorption amount of Li + was affected by the composition of different gels significantly. Different gels present different adsorption amount with the gel derived from aminopropyltriethoxysilane (APTES) and tetraethoxysilane (TEOS) having the highest adsorption amount of 0.25 mmol/g. Ion exchange should be an important mechanism for the adsorption with the size of lithium ions exactly fits the cavity of the gel adsorbents.

The adsorption of Cs + by a novel extractant-impregnated resin (EIR), was studied using batch adsorption experiments. The new EIR was prepared by impregnating 4-tert-butyl-2-(α-methylbenzyl) phenol (t-BAMBP) onto AB-8 macroporous resin beads. Thermogravimetric analysis (TG) and the Fourier Transform Infrared Spectroscopy (FTIR) were used to characterize the EIR. The effects of extraction time, pH values, metal ion concentration, and temperature were investigated. The adsorption results showed that the adsorption amount of Cs was increasing with the pH values and Cs concentration and decreasing with the temperature of the solution. The effect of co-existing ions Na + and K + on the adsorption was not obviously. Regeneration and recycling of the resin indicated the EIR can be used for continuous cycles.