الفهرس 
Chapter 1 : Introduction
Part IOnly 14 pages are availabe for public view
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Abstract
Metal capacity values in mmol/g showed that PCB-modified resin has its highest affmity towards the removal of Copper (II) along with fast equilibration process with all the studied metalions. The effect of medium and temperature on the stability of the modified resin was investigated and discussed. On the other hand, regeneration of PCB-modified resin after the first sorption of metal ion was successfully achieved using diethylenetriamine, which acts as a noooanionic complexing eluent. Moreover, the distribution coefficient values determined for a mixture of five divalent metal ions: Cu, Ni, Zn, Cd and Pb or their copper binary mixtures demonstrate the potential use of the newly synthesized PCB-modified resin for selective separation of Cu(lI). Chelating polymers are widely used as solid phase extractors in analytical chemistry for purposes of preconcentration and/or separation of metal ions from interfering concomitants prior to their determination. The selectivity of the polymer immobilized organic reagents towards metal ion sorption is greatly related to the nature of the function group present in the organic moiety. The organic compounds capabl~ of forming metal cltelates usually contain oxygen, sulphur, nitrogen and phosphorous as lone pair donor atoms. These chelating compounds can be fixed to a polymer support by two main routes, i-Chemically by covalent bonding through chemical reaction with different polymeric matrices (viz., copolymer of styrene, acrylonitrile and methacrylate ... etc.,) [1-8] or by the synthesis of such solid phase extractors from monomer ligands as in formaldehyde condensate [9-10] ii-Physically by adsorption in which the ligands can be loaded firstly to the polymer [11-12] or added to the metal ion contained matrix, where the resulting complex is then sorbed by the polymer support [13-14]. In addition to these chelating polymers, a significant number of publications dealing with collecting and separation of trace amounts of ions using aromatic complexing agents containing sulphonic acid groups loaded simply to strongly basic anion exchangers through an ion exchange mechanism are given in the literature [15-20]. Various solid phase extractors of this kind can be produced by changing the chelating agents which incorporate an anionic group that is not involved in the chelation of m~tal ions,• e.g., a sulphonate group without recourse to the usual procedures used for covalent linking of the reagents to the resin. backbone, which are. often difficult and time consuming. In this context, selective separation of metal ions has been achieved using chelate forming resins prepared by modification of conventional anion exchangers.