Abstract:Soil around uranium mine tailings was taken as research object. Mechanism of soil adsorption of radionuclide uranium, rule of migration and transformation of uranium in soil and influence of occurrence form were studied through leaching experiments under action of different phosphates. The results show that with increase of leaching time, pH value of leachate rises because of exchange and desorption reaction between dihydrogen phosphate and hydroxyl in soil. After adding phosphate to soil, uranium concentration in leachate is lower than the discharge standard of mine wastewater. After leaching, uranium content in soil drops with increase of depth, and residual uranium content in soil rises obviously, which indicates that phosphate can fix uranium in soil to a certain extent, in which potassium dihydrogen phosphate has the best effect. FTIR analysis shows that main functional groups of uranium adsorption in soil are —OH, COO—, C—O and —NH2.