Sb(Ⅲ) is often detected in contaminated soil and groundwater. Hence, high-efficiency technology is needed. In this study, bimetallic organic frameworks were used for the first time to immobilize Sb(Ⅲ) from contamina...Sb(Ⅲ) is often detected in contaminated soil and groundwater. Hence, high-efficiency technology is needed. In this study, bimetallic organic frameworks were used for the first time to immobilize Sb(Ⅲ) from contaminated soil and groundwater. The materials were synthesized by the hydrothermal method. Both ends of the prepared material were hexagonal tip rods,and the length became shorter as the ratio of Fe/Mg decreased. The bimetallic organic framework with a Fe/Mg feeding ratio of 0.5 was the optimum material for Sb(Ⅲ) removal, which could effectively immobilize Sb(Ⅲ). The adsorption isotherm was fitted well with the Freundlich model, and the optimal adsorption capacity can reach 106.97 mg/g. The adsorption capacity of 84% can be completed in 10 min, which conformed to the pseudo-second-order kinetics. The Fe^(3+)could enhance the stability of the material, and the Mg^(2+)was conducive to freeing up adsorption sites for binding Sb(Ⅲ) and forming stable chemical adsorption. Ion exchange is the predominant mechanism to remove Sb(Ⅲ). After 14 days of remediation of Sb(Ⅲ) contaminated soil, the Toxicity Characteristic Leaching Procedure(TCLP)-leached concentrations of Sb(Ⅲ) were reduced by 86%, 91% and 94% when the material dosages were1%, 2% and 3%, respectively. Immobilization of Sb(Ⅲ) in soil resulted in a conversion of antimony speciation from more easily bioavailable species to less bioavailable species, further contributing to reduce the environmental risk of antimony. The results indicate that ferromagnesium bimetallic organic frameworks may serve as a kind of promising materials for the immobilization of Sb(Ⅲ) in contaminated soil and groundwater.展开更多
基金supported by the National Key Research and Development Program of China (Nos. 2019YFA1805902 and 2019YFA0210402)the Guangdong Science and Technology Program (No. 2020B121201003)+3 种基金the Guangxi Science and Technology Base and Talent Special Project (No. 2019AC_(2)0054)the Guangxi Natural Science Foundation (Nos. 2018JJA130034, 2018JJB130018)the Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation, Beibu Gulf University (Nos. 2021KA01, 2022ZB01)the High-level Talents Research Initiation Project of Beibu Gulf University (Nos. 2018KYQD13, 2018KYQD14)。
文摘Sb(Ⅲ) is often detected in contaminated soil and groundwater. Hence, high-efficiency technology is needed. In this study, bimetallic organic frameworks were used for the first time to immobilize Sb(Ⅲ) from contaminated soil and groundwater. The materials were synthesized by the hydrothermal method. Both ends of the prepared material were hexagonal tip rods,and the length became shorter as the ratio of Fe/Mg decreased. The bimetallic organic framework with a Fe/Mg feeding ratio of 0.5 was the optimum material for Sb(Ⅲ) removal, which could effectively immobilize Sb(Ⅲ). The adsorption isotherm was fitted well with the Freundlich model, and the optimal adsorption capacity can reach 106.97 mg/g. The adsorption capacity of 84% can be completed in 10 min, which conformed to the pseudo-second-order kinetics. The Fe^(3+)could enhance the stability of the material, and the Mg^(2+)was conducive to freeing up adsorption sites for binding Sb(Ⅲ) and forming stable chemical adsorption. Ion exchange is the predominant mechanism to remove Sb(Ⅲ). After 14 days of remediation of Sb(Ⅲ) contaminated soil, the Toxicity Characteristic Leaching Procedure(TCLP)-leached concentrations of Sb(Ⅲ) were reduced by 86%, 91% and 94% when the material dosages were1%, 2% and 3%, respectively. Immobilization of Sb(Ⅲ) in soil resulted in a conversion of antimony speciation from more easily bioavailable species to less bioavailable species, further contributing to reduce the environmental risk of antimony. The results indicate that ferromagnesium bimetallic organic frameworks may serve as a kind of promising materials for the immobilization of Sb(Ⅲ) in contaminated soil and groundwater.
