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Thorium is an enabling natural radioactive elements exist in nature, in nuclear energy has broad application prospects, the future can effectively supplement the shortage of uranium resources. However, like other heavy metals thorium as a chemical toxicity, thorium and its compounds may cause many environmental problems, so a reliable method for its environmental and geological samples for accurate measurement and recovery is very important. However, due to thorium content of the sample is very low in the actual environment, serious matrix interference, often resulting in inaccurate test results. Separation and enrichment of samples, is the key to solve this problem. Solid-phase extraction (SPE) is the most popular method of sample preparation, but the traditional solid-phase extraction material difference to the target ion selectivity, the latest ion imprinting technique can achieve high selectivity for target ion extraction. Ion imprinted materials distinguishing feature is in harsh environments such as high temperature and pressure, while stable, showing the template highly selective and specific recognition capabilities. Use of such materials on the trace object for solid phase extraction and preconcentration from a complex matrix and other coexisting selective separation of the target elements can effectively purify the presence of the target environment, which is an ordinary solid-phase extraction material can not be achieved The. Therefore, this thesis is based on ion imprinted thorium (IV) ion imprinted polymer preparation and properties of solid-phase extraction. Mainly includes the following three aspects: 1. Thorium overview of separation and enrichment methods, molecular (ion) imprinting technology, the basic principles of molecular (ionic) imprinted polymer preparation methods for a more comprehensive overview, overview the IIPs-SPE research related to the field. (2) synthesis of a new functional monomer, 1 - phenyl-3-methylthio-4-carbonitrile-5 - acrylic acid amide group - pyrazole (PMTCAACP), through amino groups and maleic anhydride double bond into silicone surface, surface grafting prepared thorium (IV) ion imprinted silica sorbents. Detailed study of the adsorbent thorium (IV) in a variety of experimental conditions, kinetic properties, thermodynamic properties and adsorption mechanism. The imprinted adsorbent thorium (IV) with high selectivity and affinity adsorption. The maximum adsorption capacity of the static and dynamic adsorption capacity was 64.8 mg / g and 37.4 mg / g. Th (IV) / U (VI), Th (IV) / Ce (III), Th (IV) / La (III), and Th (IV) / Zr (IV) relative selectivity coefficients were 72.9,89.6, 93.8 and 137.2. The blot was built with material as solid phase extraction sorbent in combination with spectrophotometric determination of thorium (IV), a new method for the relative standard deviation was 2.47% (n = 7), enrichment factor of 20.2, the detection limit is 0.43μg / L, and the method used for the actual sample enrichment and determination of thorium and achieved satisfactory results. 3 The use of silicone surface grafting techniques to methacrylic acid (MAA) as the functional monomer was prepared by a new type of thorium (IV) ion imprinted polymer. The adsorbent was studied thorium (IV) characteristics of the separation and enrichment. The imprinted particles on the thorium (IV) with good recognition and relatively fast kinetics. The maximum adsorption capacity of the static and dynamic adsorption capacity was 33.2 mg / g and 17.3 mg / g. Th (IV) / U (VI), Th (IV) / Ce (III), Th (IV) / La (III), and Th (IV) / Zr (IV) relative selectivity coefficients were 58.8, 107, 106.4 and 151.7. The blot was used as SPE sorbent material spectrophotometry combined with the determination of the optimal conditions of thorium (IV), the relative standard deviation was 2.1% (n = 7), enrichment factor of 14.6, the detection limit was 0.59μg / L, and the method used for the actual water sample enrichment and determination of thorium and achieved satisfactory results.
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