| The solid phase extraction method was used in this paper, the choice of solid phase adsorption material was an important factor in the impact of selectivity and sensitivity, so looked for the superior performance of the adsorption material was a focus of this technology. On the base of a large number of the literature, the melamine - formaldehyde - triethylenetetramine (MF-TETA) resin and its chemical modification material have been synthesized. The performance of adsorption on the trace gold, silver and palladium with the MF-TETA resin and its chemical modification material was systematically studied. Thereby a new method was established with high sensitivity and selectivity of trace metals. Thesis was divided into five chapters:1. Literature review briefly introduced the analysis of the significance and analysis methods of precious metals, and the research and application of various resin materials'enrichment and separation in the precious metal. The characteristics and application in separation/preconcentration of melamine– formaldehyde resin and its chemical modification material were studied.2. A novel melamine-formaldehyde-TETA separation resin (MF-TETA) was synthesized with melamine and TETA as raw materials and formadehyde as crosslinking agent. Its separation and preconcentration properties on the trace level of silver was studied. The optimal working conditions and the adsorbing principle for the determination of silver were studied. The adsorption capacity (Q_s) was 32 mg/g. The limit of detection (LOD) of the method was found to be 16 ng/mL (3σ, n =11). The method has been applied to the determination of silver in Chinese herbal medicine with satisfactory results.3. Under dynamic conditions with MF-TETA resin as the stationary phase, FAAS for the detection and discussed the adsorption performance of MF-TETA resin on trace gold in detail. The main factors of adsorption and elution on the gold were systematically studied. The optimal adsorption and elution conditions were studied. The linear range was 0.02 ~ 9.0μg/mL, the limit of detection(LOD)was 3.38 ng/mL (3σ, n = 11), the method has been successfully applied to the determination of trace gold in water.4. The flow injection preconcentration coupled with FAAS, MF-TETA resin as adsorption micro-column, systematically studied the adsorption properties of palladium by the MF-TETA resin. The resin could be quantitatively adsorb palladium with pH 5.0, flow rate of 2.5 mL/min and time of 120 s; eluted with 0.16 mol/L thioured + 0.4 mol/L HCl. The method has been used for the determination of trace palladium in the catalysts with satisfactory results.5. Modified with rhodanine, MF-TETA-rhodanine chelating resin was synthesized as adsorption material, FAAS method for the detection, systematically studied the adsorption performance by MF-TETA-rhodanine resin on gold. Investigated the main factors of the adsorption and elution on gold in detail, determined the optimal experimental conditions. The limit of detection (LOD) was 2.35 ng/mL (3σ, n = 11), RSD was 2.2%. This method has been successfully used for the determination of trace gold in the slag. |
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