| Zinc and its stable isotopes have been widely used in agriculture, medicine, biochemistry and nuclear industry.64Zn-depleted zinc is considered as a useful material for the cooling water treatment in light water nuclear power plants. Small amount of 64Zn-depleted zinc was added to the coolant water system and can be greatly suppress the radioactivity of 60Co. In order to satisfy the increase demands of 64Zn-depleted zinc, realize the scale separation of zinc isotope, present thesis studied the methods and influence factors of zinc isotope sepration, the main contents as follows:Crown ether resin and macroporous chelating cation exchange resin were selected as the medium and applied to the chromatographic zinc isotope separation.The influences of benzo crown structure, solvents and migration distances on the zinc isotope separation were investigated. The result shows that the cavity size of benzo-15-crown-5 was most suitable to zinc ion and the separation must be operated under the dehydrated organic solvent. Dehydrated acetone was selected as the suitable solvent for zinc isotope separation. The isotope separation coefficient of zinc under 298±1 K, benzo-15-crown-5 resin,5 m migration distance and acetone solvent were 8.07×10-4,5.17×10-4 for isotopic pair of 68Zn/64Zn and 66Zn/64Zn, respectively, and HETP= 0.21 cm.Macroporous chelating exchange resin, as an alternative, was applied to zinc isotope separation. The thesis studied the effects of effluent, flow rate and the section area of column under four ligand conditions. Chelating exchange resin has higher zinc adsorption capacity than crown ether resin and EDTA ligand has bigger separation coefficient. The flow rate of effluents and section aera of columns have no obvious effect to separation coefficient; however, they can affect the HETP value. Under the condition of 298±1 K, chelation exchange resin,5 m migration distance and EDTA as effluent, the isotope separation coefficient of zinc for isotopic pair of 68Zn/64Zn and 66Zn/64Zn was obtained as:7.17×10-4 and 3.11x10-4, respectively, and HETP= 0.15 cm.With the application of zinc and zinc isotopes, it has the potential hazard to the soil environment. The thesis also studied the sorption and migration of zinc in soil under simulated rainfall and mainly studied the effect of rainfall, pH, and kind of effluents. Citrate effluent could obviously reduce the distribution of zinc in soil with wide range of pH and could be expected to select as an effective effluent for soil pollution by zinc ion.
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