| With the rapid development of industrialization, human life is facing a severe test for environmental pollution and resource plummeted. Separate and enrich useful material from waste environmental samples become a necessary issue to study for analysis chemical workers. In the modern times, the objects of chemical analysis are more complex, the contents of the component under test are lower. Although there are many high sensitivity and good selectivity instruments, the accurate determined results are difficult to obtain because of matrix effects and other kinds of interference. So sample pretreatment---separation and preconcentration become the important part of the analysis methods. Appropriate separation method and various adsorbents displayed higher selectivity and greater adsorption capacities are necessary content for separation and concentration. In the thesis, in order to establish separation and enrichment trace component method, a series of functional material was synthesized and its selective adsorption performance was examined systematically. Specific work can be divided into three parts:1. Novel solid phase extraction material BT-NHED was synthesized, new material bentonite was selected as a carrier, CPTS was used as silane coupling agent. FT-IR, elemental analysis, thermal analysis techniques were used to characterized BT-NHED. The result showed that bentonite was modified successfully by N-(2-hydroxyethyl) ethylenediamine. BT-NHED could be applied to separate and enrich Sm(Ⅲ) from shrubs leaves. The result show that:2 min is enough to reach equilibrium, the saturated adsorption capacity of Sm(Ⅲ) is 17.7 mg g-1, adsorbed Sm(Ⅲ) could be desorbed from the column by 2 mL 0.1 mol L-1 HC1 and 5% thiourea solution. The detection limit of the method is 0.60 ng mL-1, the relative standard deviation was less than 3% and the result is satisfactory. 2.2,6-diaminopyridine modified activated carbon was synthesized and the reaction only need one step. The new material AC-DAP possesses a good adsorbed selectivity and higher adsorption capacity. Bath and column procedure was used to study the adsorption properties of AC-DAP. The result show that:at pH 1 the maximum adsorption capacity of Au(Ⅲ), Pd(Ⅱ) and Pt(Ⅳ) is 202.7,38.5 and 30.1 mg g-1, respectively. The relative standard deviation (RSD) of the method was less than 3%. The method can separate and enrich noble metal Au(Ⅲ), Pd(Ⅱ) and Pt(Ⅳ) of alloy samples. The most important is that the preparation of the material is simple, the cost is low but the application value is very high.3. Novel functional solid-phase extraction was synthesized under the following condition:CPTS was used as silane coupling agent,3,6-diamine-P-amino benzamide was grafted onto the surface of activated silica gel.3,6-diamine-P-aminobenzamide was chose to be modifier for its excellent coordination ability for heavy metal ions. The material possesses an unique selectivity for Pb(Ⅱ) and can be successfully applied to the separation and enrichment of Pb(Ⅱ) in environmental samples. Parameters of solid-phase extraction were optimized in the experiment and the method was established based on the optimization results. The concentration of Pb(Ⅱ) in environmental samples was determined by ICP-AES. The detection limit of the method is 0.39μg mL-1; relative standard deviation was less than 3%, which indicate that the method is sensitive, accuracy and reliability.
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