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Chromium is a common heavy metal pollutants in the environment, pollution comes mainly from chrome ore smelting, electroplating, tanning and chemical industrial production and industrial emissions of chromium-containing waste gas, waste water and waste residue. The nature of inorganic chromium common form of Cr (III) and Cr (VI). Cr (VI) has been considered to be hazardous to health, Cr (VI) is thermodynamically more stable valence, usually anionic form. Cr (VI) Cr (III) is easier to penetrate the cell membrane and into the cell, is easily absorbed by the body and accumulate in the body. Cr (VI) in the physiological pH range of reaction with DNA, the major toxicity of Cr (VI) is reduced to Cr (III), due to memory cells in other reducing substances, the restore process generated a lot of intermediate products, such as Cr (IV) and Cr (V), and these intermediates can react with DNA helicase or fracture caused by Cr (IV) carcinogenic change, teratogenic, mutagenic effect. Cr (VI) into the human body through the water, air and food, the compound can not be natural degradation, a serious impact on human health. Cr (Ⅲ) is kinetically stable under neutral conditions, it is easy to precipitation or adsorption on the surface of the inorganic or organic, reactive differential, it is not easy through the cell membranes, low absorption rate of the animals and plants which are considered basic non-toxic. Usually by chemical reduction of Cr (VI) reduced to Cr (III), thereby reducing the Cr (VI) pollution of the environment, thereby reducing the dangers of biological systems. This thesis, 1,2 - butanediol, 1,3 - butanediol, lactic acid hydroxyl-containing organic small molecule compounds with Cr (VI) compounds response characteristics. Using the traditional spectrophotometry tracking reaction kinetics; chemical methods and infrared spectroscopy and other analytical tools to identify and characterize the oxidation products; oxidation products and kinetic data analysis, design obtained hydroxy compounds with Cr (VI) compounds possible reaction mechanism. Rate equation derived by the reaction mechanism can well explain the experimental results obtained by the rate-controlling step rate constant at different temperatures and at 298.15 K activation parameters or thermodynamic parameters. Experiments we studied pH range ([H] = 0.10-0.80 mol · L-1), based on the presence of chromic acid-base balance, by theoretical calculations to determine the dominant form of Cr (VI) in acidic solution is HCrO4-and H2CrO4. Experiments we found: 2,2 '- bipyridine solubility in the aqueous solution of dimethyl sulfoxide is greater than its solubility in the aqueous solution in dioxane, 1,3 - butanediol, the rate of reduction of Cr (VI) in dimethyl sulfoxide solution than in aqueous solution to a large, fast response and 2,2 '- bipyridine as a catalyst in EDTA as the catalyst system. Our exploration and study will be looking for Cr (VI) into Cr (III) an effective way to reduce the toxicity of Cr (VI), to reduce pollution of the environment, Cr (VI) quantitative analysis and chromium morphological analysis provide some theoretical basis. System Dynamics macro phenomena such reaction system, will Complexes microstructure reasonable explanation, speculated that the reaction process with the structure and stability of the material may transition state, and the development of the theory of coordination chemistry have important guiding significance.
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