With the widespread application of radionuclide235 U(Ⅵ), it is inevitable that part of U(Ⅵ) is released into the natural environment. The potential toxicity and irreversibility impact on the natural environment has ...With the widespread application of radionuclide235 U(Ⅵ), it is inevitable that part of U(Ⅵ) is released into the natural environment. The potential toxicity and irreversibility impact on the natural environment has become one of the most forefront pollution problems in nuclear energy utilization. In this work, rod-like metal-organic framework(MOF-5) nanomaterial was synthesized by a solvothermal method and applied to efficiently adsorb U(Ⅵ) from aqueous solutions. The batch experimental results showed that the sorption of U(Ⅵ) on MOF-5 was strongly dependent on p H and independent of ionic strength, indicating that the dominant interaction mechanism was inner-sphere surface complexation and electrostatic interaction. The maximum sorption capacity of U(Ⅵ) on MOF-5 was 237.0 mg/g at p H 5.0 and T = 298 K, and the sorption equilibrium reached within 5 min. The thermodynamic parameters indicated that the removal of U(Ⅵ) on MOF-5 was a spontaneous and endothermic process. Additionally, the FT-IR and XPS analyses implied that the high sorption capacity of U(Ⅵ) on MOF-5 was mainly attributed to the abundant oxygen-containing functional groups(i.e., CAO and C@O). Such a facile preparation method and efficient removal performance highlighted the application of MOF-5 as a candidate for rapid and efficient radionuclide contamination's elimination in practical applications.展开更多
Radionuclides with long half-life are toxic,and thereby result in serious threat to human beings and ecological balance.Herein,a simple two-step synthesis method was used to prepare manganese dioxide@polypyrrole(Mn O_...Radionuclides with long half-life are toxic,and thereby result in serious threat to human beings and ecological balance.Herein,a simple two-step synthesis method was used to prepare manganese dioxide@polypyrrole(Mn O_2@PPy)core/shell structures for efficient removal of U(Ⅵ)and Eu(Ⅲ)from aqueous solutions.The adsorption of U(Ⅵ)and Eu(Ⅲ)were investigated under different kinds of experimental conditions.The experimental results suggested that the adsorption of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were greatly affected by p H.U(Ⅵ)adsorption on Mn O_2@PPy was independent of ionic strength at p H<6.0,and dependent on ionic strength at p H>6.0.However,Eu(Ⅲ)adsorption on Mn O_2@PPy was independent of ionic strength at the whole p H range of experimental conditions.The maximum adsorption capacities(q_(max))of U(Ⅵ)and Eu(Ⅲ)were 63.04 and54.74 mg g^(-1)at T=298 K,respectively.The BET,XRD,FTIR and XPS analysis evidenced that high adsorption capacities of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were mainly due to high surface area and rich metal oxygen-containing group(i.e.,Mn–OH and Mn–O),and the interaction was mainly attributed to strong surface complexation and electrostatic interaction.This study highlighted the excellent adsorption performance of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy and could provide the reference for the elimination of radionuclides in real wastewater management.展开更多
Covalent organic frameworks(COFs)are a new type of crystalline porous polymers known for chemical stability,excellent structural regularity,robust framework,and inherent porosity,making them promising materials for ca...Covalent organic frameworks(COFs)are a new type of crystalline porous polymers known for chemical stability,excellent structural regularity,robust framework,and inherent porosity,making them promising materials for capturing various types of pollutants from aqueous solutions.This review thoroughly presents the recent progress and advances of COFs and COF-based materials as superior adsorbents for the efficient removal of toxic heavy metal ions,radionuclides,and organic pollutants.Information about the interaction mechanisms between various pollutants and COF-based materials are summarized from the macroscopic and microscopic standpoints,including batch experiments,theoretical calculations,and advanced spectroscopy analysis.The adsorption properties of various COF-based materials are assessed and compared with other widely used adsorbents.Several commonly used strategies to enhance COF-based materials’adsorption performance and the relationship between structural property and sorption ability are also discussed.Finally,a summary and perspective on the opportunities and challenges of COFs and COF-based materials are proposed to provide some inspiring information on designing and fabricating COFs and COF-based materials for environmental pollution management.展开更多
基金supported by the National Key Research and Development Program of China(2017YFA0207002)the National Natural Science Foundation of China(21577032,21607042)+1 种基金the Fundamental Research Funds for the Central Universities(2018ZD11,2018MS114,and 2016MS02)the Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection and the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘With the widespread application of radionuclide235 U(Ⅵ), it is inevitable that part of U(Ⅵ) is released into the natural environment. The potential toxicity and irreversibility impact on the natural environment has become one of the most forefront pollution problems in nuclear energy utilization. In this work, rod-like metal-organic framework(MOF-5) nanomaterial was synthesized by a solvothermal method and applied to efficiently adsorb U(Ⅵ) from aqueous solutions. The batch experimental results showed that the sorption of U(Ⅵ) on MOF-5 was strongly dependent on p H and independent of ionic strength, indicating that the dominant interaction mechanism was inner-sphere surface complexation and electrostatic interaction. The maximum sorption capacity of U(Ⅵ) on MOF-5 was 237.0 mg/g at p H 5.0 and T = 298 K, and the sorption equilibrium reached within 5 min. The thermodynamic parameters indicated that the removal of U(Ⅵ) on MOF-5 was a spontaneous and endothermic process. Additionally, the FT-IR and XPS analyses implied that the high sorption capacity of U(Ⅵ) on MOF-5 was mainly attributed to the abundant oxygen-containing functional groups(i.e., CAO and C@O). Such a facile preparation method and efficient removal performance highlighted the application of MOF-5 as a candidate for rapid and efficient radionuclide contamination's elimination in practical applications.
基金supported by the National Key Research and Development Program of China (2017YFA0207002)the National Natural Science Foundation of China (21577032)+1 种基金the Fundamental Research Funds for the Central Universities (2018ZD11, 2018MS114)the Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection and the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Radionuclides with long half-life are toxic,and thereby result in serious threat to human beings and ecological balance.Herein,a simple two-step synthesis method was used to prepare manganese dioxide@polypyrrole(Mn O_2@PPy)core/shell structures for efficient removal of U(Ⅵ)and Eu(Ⅲ)from aqueous solutions.The adsorption of U(Ⅵ)and Eu(Ⅲ)were investigated under different kinds of experimental conditions.The experimental results suggested that the adsorption of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were greatly affected by p H.U(Ⅵ)adsorption on Mn O_2@PPy was independent of ionic strength at p H<6.0,and dependent on ionic strength at p H>6.0.However,Eu(Ⅲ)adsorption on Mn O_2@PPy was independent of ionic strength at the whole p H range of experimental conditions.The maximum adsorption capacities(q_(max))of U(Ⅵ)and Eu(Ⅲ)were 63.04 and54.74 mg g^(-1)at T=298 K,respectively.The BET,XRD,FTIR and XPS analysis evidenced that high adsorption capacities of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were mainly due to high surface area and rich metal oxygen-containing group(i.e.,Mn–OH and Mn–O),and the interaction was mainly attributed to strong surface complexation and electrostatic interaction.This study highlighted the excellent adsorption performance of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy and could provide the reference for the elimination of radionuclides in real wastewater management.
基金Financial support from NSFC(21836001)National Key Research and Development Program of China(2017YFA0207002 and 2018YFC1900105)+1 种基金Science Challenge Project(TZ2016004)Beijing Outstanding Young Scientist Program were greatly appreciated.
文摘Covalent organic frameworks(COFs)are a new type of crystalline porous polymers known for chemical stability,excellent structural regularity,robust framework,and inherent porosity,making them promising materials for capturing various types of pollutants from aqueous solutions.This review thoroughly presents the recent progress and advances of COFs and COF-based materials as superior adsorbents for the efficient removal of toxic heavy metal ions,radionuclides,and organic pollutants.Information about the interaction mechanisms between various pollutants and COF-based materials are summarized from the macroscopic and microscopic standpoints,including batch experiments,theoretical calculations,and advanced spectroscopy analysis.The adsorption properties of various COF-based materials are assessed and compared with other widely used adsorbents.Several commonly used strategies to enhance COF-based materials’adsorption performance and the relationship between structural property and sorption ability are also discussed.Finally,a summary and perspective on the opportunities and challenges of COFs and COF-based materials are proposed to provide some inspiring information on designing and fabricating COFs and COF-based materials for environmental pollution management.
