In recent years, most of domestic and foreign researches about heavy metal pollutions of metal mine mainly focus on water, soil and plants on the surface. There is lack of researches about heavy metal pollution in gro...In recent years, most of domestic and foreign researches about heavy metal pollutions of metal mine mainly focus on water, soil and plants on the surface. There is lack of researches about heavy metal pollution in groundwater of metal mine. In this research, a certain antimony mine area is selected as a typical study area. Also, the study about statistical characteristics of heavy metals in groundwater has been carried out. Furthermore, the interrelationships have been preliminarily discussed through related analysis, such as relevant analysis, cluster analysis and principle component analysis. The results show that: the excessive elements in groundwater of study area are Sb, As, Pb, Se, and Ni. The average mass concentration of Sb, As, and Pb is higher than that of drinking water standards(GB5749-2006). The concentration of most heavy metals in dry season is lower than or equal to that in wet season for groundwater. Zn is the only metal in groundwater showing a different pattern, the concentration of which in dry season is higher than that in wet season. Under the impacts of stratum leaching and absorption effect, the concentration of heavy metals(except Pb and Ba) in groundwater are lower than or equal to that in surface water. As and Se, the two heavy metals have a significant positive correlation, which shows the two elements might have gone through similar environmental geochemical effect. Also, the connection among Zn, Hg, Pb, and Mn is not obvious; therefore, the sources of those elements are quite different. In addition, the elements of Se and As have obvious positive interrelationship with elements of CO_3^(2-) and F^-. Also, the Pb has significant positive correlation with PO_4^(3-), H_2SiO_3 and oxygen consumption. The results of cluster analysis show that 9 different heavy metals in the study area can be divided into 3 categories: Zn, Cd, Mn, Hg, Cu, and Cr belong to the first category, Se and As belong to the second one, and the last category is Pb. Also, the principle component analysis divides 6 heavy metals(Zn, As, Hg, Pb, Mn, and Se) into 4 different principle components, which can be utilized to assess heavy metals pollution situations in groundwater. The reliability of this method is higher than 91%. Moreover, the research provides theory basis and models for establishing evaluation index system and exploring the evaluation method of heavy mental pollution in groundwater.展开更多
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 Homeland Resource Non-Profit Research Special Funding Project(No.200911036)
文摘In recent years, most of domestic and foreign researches about heavy metal pollutions of metal mine mainly focus on water, soil and plants on the surface. There is lack of researches about heavy metal pollution in groundwater of metal mine. In this research, a certain antimony mine area is selected as a typical study area. Also, the study about statistical characteristics of heavy metals in groundwater has been carried out. Furthermore, the interrelationships have been preliminarily discussed through related analysis, such as relevant analysis, cluster analysis and principle component analysis. The results show that: the excessive elements in groundwater of study area are Sb, As, Pb, Se, and Ni. The average mass concentration of Sb, As, and Pb is higher than that of drinking water standards(GB5749-2006). The concentration of most heavy metals in dry season is lower than or equal to that in wet season for groundwater. Zn is the only metal in groundwater showing a different pattern, the concentration of which in dry season is higher than that in wet season. Under the impacts of stratum leaching and absorption effect, the concentration of heavy metals(except Pb and Ba) in groundwater are lower than or equal to that in surface water. As and Se, the two heavy metals have a significant positive correlation, which shows the two elements might have gone through similar environmental geochemical effect. Also, the connection among Zn, Hg, Pb, and Mn is not obvious; therefore, the sources of those elements are quite different. In addition, the elements of Se and As have obvious positive interrelationship with elements of CO_3^(2-) and F^-. Also, the Pb has significant positive correlation with PO_4^(3-), H_2SiO_3 and oxygen consumption. The results of cluster analysis show that 9 different heavy metals in the study area can be divided into 3 categories: Zn, Cd, Mn, Hg, Cu, and Cr belong to the first category, Se and As belong to the second one, and the last category is Pb. Also, the principle component analysis divides 6 heavy metals(Zn, As, Hg, Pb, Mn, and Se) into 4 different principle components, which can be utilized to assess heavy metals pollution situations in groundwater. The reliability of this method is higher than 91%. Moreover, the research provides theory basis and models for establishing evaluation index system and exploring the evaluation method of heavy mental pollution in groundwater.
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.
