【摘要】 为了降低U（Ⅵ）在水中的溶解性，缩小铀污染的可迁移范围，将蒙脱石改造为铁氧化物/蒙脱石并与希瓦氏菌MR-1（Shewanella oneidensis MR-1）构成联合体系，以实现在厌氧条件下对U（Ⅵ）的生物还原。制备了铁氧化物/蒙脱石复合体并对其形貌结构进行了表征；分析了矿物-微生物联合还原体系中U（Ⅵ）,Fe（Ⅱ）含量的变化和矿物-微生物-腐殖酸联合体系中U（Ⅵ）,Fe（Ⅱ）含量的变化；讨论了矿物-微生物联合体系对U（Ⅵ）的生物还原过程及还原途径。结果表明：蒙脱石在合成为铁氧化物/蒙脱石后，其层状结构变化不大，但引入了含量不等的Fe,其中纤铁矿中引入的Fe原子含量最高（67.71%）;在矿物-微生物联合体系中，纤铁矿/蒙脱石联合希瓦氏菌MR-1体系对U（Ⅵ）的还原能力最高，在铀浓度50 mg·L^-1处理组中的还原率为85.8%,Fe（Ⅱ）的含量与U（Ⅵ）浓度呈反比关系，在反应的0～3 h时迅速上升；在矿物-微生物-腐殖酸复合体系中，腐殖酸浓度对还原U（Ⅵ）的影响表现为“完全促进”“低促高抑”和“高促低抑” 3种现象，对联合体系中的Fe（Ⅱ）的影响主要分为抑制和促进两种类型。铁氧化物/蒙脱石与希瓦氏菌MR-1构成的联合体系在厌氧条件下能够实现对U（Ⅵ）的生物还原。更多还原

【Abstract】 In order to reduce the solubility of U（Ⅵ） in water and the migratory range of uranium pollution, montmorillonite was transformed into iron oxide/montmorillonite and formed a consortium with Shewanella oneidensis MR-1 to achieve bioreduction of U（Ⅵ） under anaerobic conditions. The iron oxide/montmorillonite composite was prepared and its morphology and structure were characterized. The changes in U（Ⅵ） and Fe（Ⅱ） contents in the mineral-microbe consortium and mineral-microbe-humic acid consortium were analyzed. The bioreduction process and pathway of U（Ⅵ） in the mineral-microbe consortium were discussed. The results show that after synthesizing montmorillonite into iron oxide/montmorillonite composite, the layer structure of montmorillonite has little change, but different amounts of Fe are introduced. And the highest content of Fe atoms is introduced by lepidocrocite（67.71%）. In the mineral-microbe consortium, the lepidocrocite/montmorillonite consortium with Shewanella oneidensis MR-1 has the highest U（Ⅵ） reduction ability, and the reduction rate is 85.8% at a uranium concentration of 50 mg·L^-1. The content of Fe（Ⅱ） is inversely proportional to the concentration of U（Ⅵ）, and it rises rapidly from 0 to 3 hours of reaction. In the mineral-microbe-humic acid composite system, the effect of humic acid concentration on the reduction of U（Ⅵ） exhibits three phenomena: “complete promotion” “low promotion and high inhibition” and “high promotion and low inhibition”. The impact on Fe（Ⅱ） in the composite system is mainly divided into two types: inhibition and promotion. The consortium of iron oxide/montmorillonite and Shewanella oneidensis MR-1 can achieve the bioreduction of U（Ⅵ） under anaerobic conditions.更多还原