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The present work was attempted to prepare three new sorbents including a poly(acrylamide-sodium styrene sulphonate) P(AM-SSS) hydrogel, a poly(hydroxamic acid-sodium styrene sulphonate) P(HA-SSS) modified polymeric resin and a poly(acrylamide-sodium styrene sulphonate-silicon oxide) P(AM-SSS-SiO 2 ) composite by irradiation template polymerization. The effective reaction parameters such as absorbed dose (kGy), crosslinker and monomer concentration, and the polymer/monomer ratio, which affect the degree of template polymerization, were optimized to get the maximum conversion percentage and high capacity. The physicochemical swelling behavior of the hydrogel was higher than the resin and the composite. Modification of the hydrogel into modified polymeric resin was achieved by using hydroxylamine hydrochloride. The modification process is indicated by FTIR characteristic absorption bands of -O-H and 4N-Ogroups of the hydroxamic groups. Furthermore, an organic-inorganic composite was prepared by introducing silica into the polymer, which is indicated by FTIR characteristic adsorption bands of the silica network at 1209 cm À1 and 960 cm À1 . The application of the prepared sorbents for removal of La 3+ , Ce 3+ , Nd 3+ , Eu 3+ and Pb 2+ from aqueous solution was investigated by a batch technique. Various factors influencing the sorption behaviors were tested such as shaking time, pH and initial metal ion concentration. The obtained results showed that the prepared composite has better uptake percentage and higher capacity than the resin and the hydrogel and the sorption efficiency of metal ions towards the three adsorbent materials obeys the order La 3+ 4 Ce 3+ 4 Nd 3+ 4 Eu 3+ 4 Pb 2+ .

These materials especially chabazite are recommended to be used as a reactive barrier for hazardous heavy metals control.

The present study was oriented to prepare new scintillating anion-exchange resins for measurement of (99)TcO(4)(-) in natural waters. The organic fluor 2-(1-naphthyl)-5-phenyloxazole was diffused into (chloromethyl)polystyrene resin. Thereafter, a thin layer of poly[[2-(methacryloyloxy)ethyl]trimethylammonium chloride] was grafted from the resin surface by surface-initiated atom transfer radical polymerization as an attempt to overcome potential problems related to the leaching of fluor molecules during usage. The residual chloromethyl groups of the polymer-coated resin were aminated by reaction with two different tertiary amines, triethylamine (TEA) and methyldioctylamine (MDOA). Off- and on-line quantification of (99)Tc was achieved with high detection efficiencies of 60.72 ± 1.93% and 72.83 ± 0.81% for resin with TEA and MDOA functional groups, respectively. The detection limit was determined to be less than the maximum contaminant level (33 Bq L(-1)) established under the Safe Drinking Water Act. The two functionalized resins were demonstrated to be selective for pertechnetate from synthetic groundwater containing up to 1000 ppm Cl(-), SO(4)(2-), and HCO(3)(-) and up to 1200 ppb Cr(2)O(7)(2-) in an acidic medium.

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