Abstract:Uranium-bearing contaminated soil of uranium mine was chemical eluted with sepiolite. Content of uranium in different particle sizes of contaminated soil was studied, and contaminated soil was repaired by stirring and elution. Influences of elution time, eluant type, temperature, and ultrasonic heating on elution effect and influences of sepiolite on enrichment of uranium in soil were discussed. The results show that uranium content in soil drops gradually with increase of soil particle size, uranium content in soil is inversely proportional to soil particle size. Except for gravel, other uranium contents exceed the uranium target repair value of 40 mg/kg. When elution time is 8 h, elution is relatively sufficient, elution effect is the best, and cost is appropriate. By improving temperature and applying ultrasonic assist methods, elution effect can be significantly improved, and enrichment effect of sepiolite is also very good. In terms of elution, citric acid has the best effect and hydrochloric acid has the worst effect; in terms of enrichment of uranium in soil by sepiolite, sulfuric acid elution has the highest enrichment ratio of uranium in soil, while citric acid elution has the lowest enrichment ratio of uranium in soil. Removal of uranium from uranium contaminated soil and enrichment of uranium in sepiolite are achieved by constructing soil-leacheate-sepiolite uranium migration path.