الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The newly synthesized modified resin showed good potential for trace enrichment of great number of transition metal ions. The methodology described offers a simple and fast means for sorption (selective and /or as a collector) and preconcentration of metal ions. The elution step does not involve use of organic solvents as other procedures. In comparison with other modified resins, the main advantages of GPHA -DC20 resin (table 30) were: higher preconcentration factor; higher sorption capacity; low matrix effect; and good precision. Results obtained showed that, DC20-DAPCH resin can quantitatively sorbs very low concentrations of the studied metal ions. Beside its stability in strongly acidic medium, the resin could be recycled for many hundred cycles without any change in its sorption properties. The short loading time (t1/2) of DAPCH- DC20- resin is another advantage. The resin has been demonstrated to be suitable for preconcentration of metal ions in samples with complicated and variable matrices like seawater and certified alloys. The application of the modified resin was extended to separate metal ions from crude petroleum oil sample as a complex organic matrix, and from ash coal as an environmental sample. from the economic point of view, the sorption capacity of the resin, after its versatile use for more than a year and store under ambient conditions, has been found to be practically unchanged.