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Within recent years, solvent extraction and coprecipitation have been increasingly replaced by sorbent (solid phase) extraction and ion exchange. The markedly lower quantity of reagents required is frequently quoted as an advantage, although this is strongly method-dependent. A further advantage is that the solid phase is packed into a column and can thus be used repeatedly. In another technique called batch procedure, the solid phase collector is placed directly into the solution matrix.The formed matrix can subsequently be eluted with the minimum volume of solvent. In this way, it is possible to achieve high enrichment or concentration factors with good separation from the matrix, especially for natural water samples. [1][2][3] The problem of good sorption and poor (slow) desorption of the analyte has been treated in a number of papers and widely varying solutions have been proposed. 4,5 Various methods of preconcentration and separation procedures, such as electrodeposition, coprecipitation, solvent extraction, evaporation and freeze drying can be used prior to the atomic absorption spectroscopic measurements. [6][7][8][9][10][11][12] Cellulose-hyphan (1-(2′-hydroxyphenylazo)-2-naphthol) as an ion-exchanger was used for the preconcentration of various trace heavy metal ions in different water samples. [13][14][15][16][17][18] Other types of ion and modified exchangers were reported. 19,20 Polymer supported organic compounds are playing an important role in many applications.Some of these organic compounds, specially those serving as chelating agents can be used as polymer-supported materials in waste water treatment as well as selective sensing and separation of some heavy metal ions.Pyridylazo-β-naphthol (PAN) is known as a famous compound that has a strong ability to form chelates with many metal ions. [20][21][22][23][24][25][26][27] The excellent performance of the atomic absorption spectrometry, AAS as a precise and rapid analytical tool, allows the fast acquisition of data on samples introduced into a flame. One of the attractive characters of the AAS technique is its ease of operation. 1,28The present work aims to throw light on the use of chemically modified chloromethylated polystyrene-PAN ion-exchanger as a new system for the preconcentration and separation of eleven different heavy metal ions.After preconcentration, the investigated metal ions were microdetermined in tap, Nile, sea and waste water samples, human urine, milk and some ores using AAS. Our aim is also to make some comparisons between the concentration of the present heavy metal ions in the environmental of east delta area of river Nile with that of the international level to look for any type of pollution and the reasons for such pollution, if present, in order to prevent the killing of water creatures. Experimental InstrumentationA Perkin-Elmer Model 2380 atomic absorption spectrometer (USA) was used with Pye Unicam (England) hollow-cathode lamps and a conventional 10 cm slit burner head for air-acetylene flame. Absorbance values were...

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