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Qian Y, Huang Z, Zhou G, Chen C, Sang Y, Yu Z, Jiang L, Mei Y, Wei Y. Preparation and Properties of Organically Modified Na-Montmorillonite. MATERIALS (BASEL, SWITZERLAND) 2023; 16:3184. [PMID: 37110020 PMCID: PMC10143424 DOI: 10.3390/ma16083184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/29/2023] [Accepted: 04/11/2023] [Indexed: 06/19/2023]
Abstract
This study investigates the montmorillonite (MMT) content, rotational viscosity, and colloidal index of sodium montmorillonite (Na-MMT) as a function of the sodium agent dosage, reaction time, reaction temperature, and stirring time. Na-MMT was modified using different octadecyl trimethyl ammonium chloride (OTAC) dosages under optimal sodification conditions. The organically modified MMT products were characterized via infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The results show that the Na-MMT with good properties (i.e., the maximum rotational viscosity and highest Na-MMT content with no decrease in the colloid index) was obtained at a 2.8% sodium carbonate dosage (measured based on the MMT mass), a temperature of 25 °C, and a reaction time of two hours. Upon organic modification of the optimized Na-MMT, OTAC entered the NA-MMT interlayer, and the contact angle was increased from 20.0° to 61.4°, the layer spacing was increased from 1.58 to 2.47 nm, and the thermal stability was conspicuously increased. Thus, MMT and Na-MMT were modified by the OTAC modifier.
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Affiliation(s)
- Yan Qian
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Zeen Huang
- Jiangsu Province Key Laboratory of Fine Petrochemical Engineering, Changzhou University, Changzhou 213164, China
| | - Guantao Zhou
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Chenan Chen
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Yuhang Sang
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Zuolong Yu
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Legao Jiang
- Zhejiang Hongyu New Materials Co., Ltd., Huzhou 313113, China
| | - Yuning Mei
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
| | - Yunxiao Wei
- Biology and Environment Engineering College, Zhejiang Shuren University, Hangzhou 310015, China
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Feng H, Li X, Xing Y, Xie L, Zhen S, Chang W, Zhang J. Adsorption of CO 32-/HCO 3- on a quartz surface: cluster formation, pH effects, and mechanistic aspects. Phys Chem Chem Phys 2023; 25:7951-7964. [PMID: 36866749 DOI: 10.1039/d2cp05234b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Soluble inorganic carbon is an important component of a soil carbon pool, and its fate in soils, sediments, and underground water environments has great effects on many physiochemical and geological processes. However, the dynamical processes, behaviors and mechanism of their adsorption by soil active components, such as quartz, are still unclear. The aim of this work is to systematically address the anchoring mechanism of CO32- and HCO3- on a quartz surface at different pH values. Three pH values (pH 7.5, pH 9.5 and pH 11) and three carbonate salt concentrations (0.07, 0.14 and 0.28 M) are considered, and molecular dynamics methods are used. The results indicate that the pH value regulates the adsorption behavior of CO32- and HCO3- on the quartz surface by affecting the CO32-/HCO3- ratio and the surface charge of quartz. In general, both HCO3- and CO32- ions were able to adsorb on the quartz surface and the adsorption capacity of CO32- is higher than that of HCO3-. HCO3- ions tended to uniformly distribute in an aqueous solution and contact the quartz surface in the form of single molecules instead of clusters. In contrast, CO32- ions were mainly adsorbed as clusters which became larger as the concentration increased. Na+ ions were essential for the adsorption of HCO3- and CO32-, because some of the Na+ and CO32- ions spontaneously associated together to form clusters, promoting the clusters to be adsorbed on the quartz surface through cationic bridges. The local structures and dynamics trajectory of CO32- and HCO3- showed that the anchoring mechanism of carbonate solvates on quartz involved H-bonds and cationic bridges, which changed in relation to the concentration and pH values. However, the HCO3- ions mainly adsorbed on the quartz surface via H-bonds while the CO32- ions tended to be adsorbed through cationic bridges. These results may help in understanding the geochemical behavior of soil inorganic carbon and further the processes of the Earth's carbon chemical cycle.
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Affiliation(s)
- Haotian Feng
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Xiong Li
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Yuhang Xing
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Liangchen Xie
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Shuai Zhen
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Wenqian Chang
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
| | - Jianguo Zhang
- College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, Shaanxi, China. .,Taklimakan Desert Research Station, Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences, Korla 841000, China
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Wang D, Wang R, Peng W, Zhang J, Wang Y, Huang M, Zhang N, Duan Y, Fang Y. Experimental and DFT study of Cu(II) removed by Na-montmorillonite. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 87:834-851. [PMID: 36853765 DOI: 10.2166/wst.2023.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The experimental and theoretical studies on the adsorption of Cu(II) on the surface of Na-montmorillonite (Na-Mt) were reported. Effects of batch adsorption experimental parameters were studied. Density functional theory and molecular dynamics simulations were used to study the adsorption of Cu(II) on montmorillonite (001) surface. The adsorption reached equilibrium within 80 min and the adsorption capacity was 35.23 mg·g-1 at 25 °C. The adsorption data of Cu(II) were consistent with pseudo-second-order kinetics and Langmuir isotherm models. The adsorption process was dominated by physical adsorption (Ea was 37.08 kJ·mol-1) with spontaneous endothermic behavior. The influence of coexisting cations on the adsorption capacity of Cu(II) was Mg(II) > Co(II) > Ca(II) > Na(I). The simulation results demonstrated that there were no significant differences in the adsorption energy of Cu(II) at the four adsorption sites on the montmorillonite (001) surface. Cu(II) had more electron transfer than Na(I). The diffusion coefficient of Cu(II) in the aqueous solution system containing montmorillonite was 0.85×10-10 m2·s-1. Considerable amounts of Cu(II) ions were adsorbed at a distance of 0.26 and 2.25 Å from the montmorillonite (001) surface. The simulation results provided strong supporting evidence for experimental conclusions.
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Affiliation(s)
- Danqi Wang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Ruicong Wang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Wencai Peng
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail: ; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Shihezi, Xinjiang, China
| | - Jinli Zhang
- School of Chemical Engineering, Tianjin University, Tianjin 300350, China
| | - Yi Wang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Minghui Huang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Na Zhang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Yanan Duan
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
| | - Ying Fang
- School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003, China E-mail:
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Liu L, Zhang C, Jiang W, Li X, Dai Y, Jia H. Understanding the sorption behaviors of heavy metal ions in the interlayer and nanopore of montmorillonite: A molecular dynamics study. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125976. [PMID: 34492884 DOI: 10.1016/j.jhazmat.2021.125976] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 06/13/2023]
Abstract
The molecular-scale adsorption mechanism of heavy metal ions in the interlayer and nanopore regions of montmorillonite (MMT) were investigated by molecular dynamics simulations. Three typical heavy metals (zinc, cadmium, and lead) were selected as the model ions, and two types of MMT (Arizona and Wyoming) were considered. The results showed that Cd2+ and Pb2+ can form both inner- and outer-sphere complexes on Wyoming MMT, while Zn2+ only formed outer-sphere complex due to the stronger hydration interaction of Zn2+ than Cd2+ and Pb2+. For Arizona MMT, all of the three ions only formed outer-sphere complexes on its interlayer and external basal surface in which the cations remained a fully hydrated state. The calculated diffusion coefficients of three cations in interlayer and nanopore indicated that their diffusion abilities were significantly impaired, implying that MMT adsorbents have a strong ability to fix and retard heavy metal ions. The derived results and mechanisms are instrumental to a profound understanding of the transport and retention of heavy metal elements in subsurface environments, and provide guidance for the management of heavy metal pollution.
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Affiliation(s)
- Libin Liu
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China
| | - Chi Zhang
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling 712100, China.
| | - Wenjun Jiang
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China
| | - Xiong Li
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling 712100, China
| | - Yunchao Dai
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling 712100, China
| | - Hanzhong Jia
- Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A&F University, Yangling 712100, China.
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Younes A, Ali JS, Duda A, Alliot C, Huclier-Markai S, Wang J, Kabalan F, Nemirovsky D, Deng R, Nur MT, Cao M, Groveman S, Drain CM, Alexandratos SD. Uptake and Removal of Uranium by and from Human Teeth. Chem Res Toxicol 2021; 34:880-891. [PMID: 33507734 DOI: 10.1021/acs.chemrestox.0c00503] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Uranium-238 (238U), a long-lived radiometal, is widespread in the environment because of both naturally occurring processes and anthropogenic processes. The ingestion or inhalation of large amounts of U is a major threat to humans, and its toxicity is considered mostly chemical rather than radiological. Therefore, a way to remove uranium ingested by humans from uranium-contaminated water or from the air is critically needed. This study investigated the uranium uptake by hydroxyapatite (HAP), a compound found in human bone and teeth. The uptake of U by teeth is a result of U transport as dissolved uranyl (UO22+) in contaminated water, and U adsorption has been linked to delays in both tooth eruption and development. In this present work, the influence of pH, contact time, initial U concentration, and buffer solution on the uptake and removal of U in synthetic HAP was investigated and modeled. The influence of pH (pH of human saliva, 6.7-7.4) on the uptake of uranyl was negligible. Furthermore, the kinetics were extremely fast; in one second of exposure, 98% of uranyl was uptaken by HAP. The uptake followed pseudo-second-order kinetics and a Freundlich isotherm model. A 0.2 M sodium carbonate solution removed all the uranyl from HAP after 1 h. Another series of in vitro tests were performed with real teeth as targets. We found that, for a 50 mg/L U in PBS solution adjusted to physiological pH, ∼35% of the uranyl was uptaken by the tooth after 1 h, following pseudo-first-order kinetics. Among several washing solutions tested, a commercially available carbonate, as well as a commercially available fluoride solution, enabled removal of all the uranyl taken up by the teeth.
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Affiliation(s)
- Ali Younes
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Jafar Sunga Ali
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Artem Duda
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Cyrille Alliot
- CRCNA, INSERM U892, Nantes 44007, France.,ARRONAX Cyclotron, Saint-Herblain 44800, France
| | - Sandrine Huclier-Markai
- ARRONAX Cyclotron, Saint-Herblain 44800, France.,SUBATECH (UMR 6457), IN2P3-CNRS/EMN Nantes/Université de Nantes, Nantes 44307, France
| | - Jasmine Wang
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Fatima Kabalan
- Faculty of Sciences I, Lebanese University Beirut 00000, Lebanon
| | - David Nemirovsky
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Rebecca Deng
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Mohamed Tousif Nur
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Minhua Cao
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States
| | - Samuel Groveman
- Department of Chemistry and Environmental Science, Medgar Evers College, 1650 Bedford Ave #2010, Brooklyn, New York 11225 United States
| | - Charles Michael Drain
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States.,The Graduate Center of the City University of New York, New York, New York 10016, United States
| | - Spiro D Alexandratos
- Department of Chemistry, Hunter College, 695 Park Ave, New York, New York 10065, United States.,The Graduate Center of the City University of New York, New York, New York 10016, United States
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Galicia-Andrés E, Petrov D, Gerzabek MH, Oostenbrink C, Tunega D. Polarization Effects in Simulations of Kaolinite-Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15086-15099. [PMID: 31663747 PMCID: PMC7610636 DOI: 10.1021/acs.langmuir.9b02945] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Computational models of clay minerals and their interactions with the surrounding medium are highly valuable to study adsorption processes at an atomistic resolution, which may be relevant in different areas such as chromatography, environmental chemistry, and so forth. In this work, we analyzed the effect of the treatment of long-range interactions on the polarization of kaolinite-water interfacial systems in terms of structural, electric and dynamic properties, and hydrogen bonds. When using conventional three-dimensional (3D) Ewald summation, water molecules were more structured on the alumina interface of the kaolinite compared to simulations, in which the periodicity perpendicular to the plane was effectively removed. By applying an external electric field to the latter simulations, we were able to reproduce results obtained with the 3D Ewald summation. We proved that the induced polarization promotes adsorption processes of polar and charged species from aqueous solutions using a glyphosate molecule (widely used herbicide) as a particular example. The polarization phenomena raised from the simulation setup should be accounted for carefully in simulations of adsorption processes, which involve periodic images of polar interfaces. An inappropriate treatment of long-range electrostatic interactions can easily lead to artifacts and/or erroneous results.
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Affiliation(s)
- Edgar Galicia-Andrés
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
- Institute of Soil Research, University of Natural Resources and Life Sciences, Peter-Jordan-Straße 82, 1190 Vienna, Austria
| | - Drazen Petrov
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Martin H. Gerzabek
- Institute of Soil Research, University of Natural Resources and Life Sciences, Peter-Jordan-Straße 82, 1190 Vienna, Austria
| | - Chris Oostenbrink
- Institute of Molecular Modeling and Simulation, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | - Daniel Tunega
- Institute of Soil Research, University of Natural Resources and Life Sciences, Peter-Jordan-Straße 82, 1190 Vienna, Austria
- School of Pharmaceutical Science and Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin, P.R. China
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Xie Y, Chen C, Ren X, Wang X, Wang H, Wang X. Emerging natural and tailored materials for uranium-contaminated water treatment and environmental remediation. PROGRESS IN MATERIALS SCIENCE 2019; 103:180-234. [DOI: https:/doi.org/10.1016/j.pmatsci.2019.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/25/2023]
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8
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Iakovlev E, Zhilyaev P, Akhatov I. Modeling of the phase transition inside graphene nanobubbles filled with ethane. Phys Chem Chem Phys 2019; 21:18099-18104. [DOI: 10.1039/c9cp03461g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A liquid–gas phase transition of ethane inside graphene nanobubbles below the critical temperature leads to a ‘forbidden range’ of radii, in which no stable bubbles exist.
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Affiliation(s)
- Evgeny Iakovlev
- Center for Design
- Manufacturing and Materials
- Skolkovo Institute of Science and Technology
- Skolkovo Innovation Center
- Moscow
| | - Petr Zhilyaev
- Center for Design
- Manufacturing and Materials
- Skolkovo Institute of Science and Technology
- Skolkovo Innovation Center
- Moscow
| | - Iskander Akhatov
- Center for Design
- Manufacturing and Materials
- Skolkovo Institute of Science and Technology
- Skolkovo Innovation Center
- Moscow
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Chu YB, Li M, Liu JW, Xu W, Cheng SH, Zhao HZ. Molecular insights into the mechanism and the efficiency-structure relationship of phosphorus removal by coagulation. WATER RESEARCH 2018; 147:195-203. [PMID: 30312792 DOI: 10.1016/j.watres.2018.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/07/2018] [Accepted: 10/02/2018] [Indexed: 06/08/2023]
Abstract
Types and structures of phosphorus compounds influence the removal of phosphorus by coagulation. Until now, the molecular-level interaction between coagulants and phosphorus (especially organophosphates) and the relationship between removal efficiency and phosphorus structure have not been clear. This work investigated the removal of phosphorus with different structures using conventional coagulants (poly aluminum chloride (PACl) and polymerized ferric sulfate (PFS)) and a novel covalently-bound inorganic-organic hybrid coagulant (CBHyC). CBHyC removed more than 98% of phosphate and most of organophosphates, had more stable performance than PACl and PFS, and was less affected by pH, initial phosphorus concentration, and co-occurring materials. Molecular dynamics simulation demonstrated that CBHyC removed phosphorus mainly through electrostatic attraction and hydrophobic interaction. Furthermore, this work established QSAR (quantitative structure activity relationship) models for removal efficiency and organophosphate structure for the first time. The model showed that atomic charges of phosphorus atoms (QP) and hydrogen atoms (QH+) in the system and the energy gap (ΔEMO) affected electronegativity and hydrophobicity, thus influencing organophosphate removal efficiency. The model had high fitting precision and good predictive ability and has the potential to greatly reduce the cost of optimizing processes and conditions for phosphorus removal.
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Affiliation(s)
- Yong-Bao Chu
- Department of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, People's Republic of China
| | - Min Li
- Department of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, People's Republic of China
| | - Jin-Wei Liu
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Wei Xu
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Shi-Han Cheng
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Hua-Zhang Zhao
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China.
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10
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Criscenti LJ, Ho TA, Hart D. Structural Properties of Aqueous Solutions at the (100) and (101) Goethite Surfaces by Molecular Dynamics Simulation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:14498-14510. [PMID: 30457334 DOI: 10.1021/acs.langmuir.8b02612] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Trace metal concentrations in soils and sediments are often controlled by adsorption to iron oxides such as goethite in both natural and contaminated systems. Because of goethite's importance as an adsorbent, its interaction with aqueous solutions has been studied extensively. Nonetheless, despite the use of numerous analytical and computational tools, the properties of goethite-aqueous solution interfaces are not fully understood. In this research, we investigate the interaction of water and aqueous NaCl, MgCl2, and BaCl2 solutions ranging in concentration from 0.1 to 4 M, with two goethite surfaces, (100) and (101), using classical molecular dynamics simulation. In the past, the (100) surface has been studied the most because of its simplicity; however, goethite crystals in the environment exhibit other prominent surfaces like the (101) surface which may exhibit very different adsorption properties than the (100) surface. The (100) surface has three surface sites; one is an under-coordinated Fe3+ which interacts strongly with water affecting the interfacial water structure, another site remains deprotonated and forms a hydrogen bond to the only hydroxylated surface site. The (101) surface is terminated with five hydroxyl groups that do not interact as strongly with water as the under-coordinated Fe3+ ion and that form a more corrugated surface structure. As a result, the (101) goethite-solution interface exhibits less water structure, weaker electric double layer oscillations, and more inner-sphere ion adsorption, especially for Cl- and Ba2+ ions. The fundamental differences in interfacial properties for these surfaces suggest that the adsorption properties of one goethite surface cannot be averaged to represent goethite interfaces present in soils and sediments.
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Affiliation(s)
- Louise J Criscenti
- Geochemistry Department , Sandia National Laboratories , P.O. Box 5800 MS 0754, Albuquerque , New Mexico 87185-0754 , United States
| | - Tuan A Ho
- Geochemistry Department , Sandia National Laboratories , P.O. Box 5800 MS 0754, Albuquerque , New Mexico 87185-0754 , United States
| | - David Hart
- Geochemistry Department , Sandia National Laboratories , P.O. Box 5800 MS 0754, Albuquerque , New Mexico 87185-0754 , United States
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11
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Gu P, Zhang S, Li X, Wang X, Wen T, Jehan R, Alsaedi A, Hayat T, Wang X. Recent advances in layered double hydroxide-based nanomaterials for the removal of radionuclides from aqueous solution. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 240:493-505. [PMID: 29754099 DOI: 10.1016/j.envpol.2018.04.136] [Citation(s) in RCA: 222] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 04/26/2018] [Accepted: 04/28/2018] [Indexed: 05/23/2023]
Abstract
Layered double hydroxides (LDHs), one of the most important two-dimensional layered compounds, have enabled massive developments in effective pollution treatments. Their derivative materials have also attracted multidisciplinary attention owing to the intrinsic advantages of their moderate chemiostability, low cost and nontoxicity. Over the past few decades, significant advances have been made in the synthesis of novel LDH-based composites and the optimization of characterization techniques. In this review, we give an overview of the recent advances in LDH-based nanomaterials, from a brief introduction to their preparation and modification methods to an overview of their application in the removal of radionuclides and an exploration of their underlying adsorption mechanisms. In the end, a summary and outlook are also briefly addressed. This review intends to provide deep insight into the design of high-performance LDH-based materials for the potential elimination of radionuclides from aqueous solutions during environmental pollution cleanup.
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Affiliation(s)
- Pengcheng Gu
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Sai Zhang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Xing Li
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Xiangxue Wang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Tao Wen
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Riffat Jehan
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China
| | - Ahmed Alsaedi
- NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Tasawar Hayat
- NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia; Department of Mathematics, Quaid-I-Azam University, Islamabad, 44000, Pakistan
| | - Xiangke Wang
- College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, PR China; Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions and School for Radiological and Interdisciplinary Sciences, Soochow University, 215123, Suzhou, PR China; NAAM Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
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12
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Li X, Zhu C, Jia Z, Yang G. Confinement effects and mechanistic aspects for montmorillonite nanopores. J Colloid Interface Sci 2018; 523:18-26. [PMID: 29604556 DOI: 10.1016/j.jcis.2018.03.082] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/16/2018] [Accepted: 03/24/2018] [Indexed: 11/16/2022]
Abstract
Owing to the ubiquity, critical importance and special properties, confined microenvironments have recently triggered overwhelming interest. In this work, all-atom molecular dynamics simulations have been conducted to address the confinement effects and ion-specific effects for electrolyte solutions within montmorillonite nanopores, where the pore widths vary with a wide range. The adsorption number, structure, dynamics and stability of inner- and outer-sphere metal ions are affected by the change of pore widths (confinement effects), while the extents are significantly dependent on the type of adsorbed species. The type of adsorbed species is, however, not altered by the magnitude of confinement effects, and confinement effects are similar for different electrolyte concentrations. Ion-specific effects are pronounced for all magnitudes of confinement effects (from non- to strong confined conditions), and Hofmeister sequences of outer-sphere species are closely associated with the magnitude of confinement effects while those of inner-sphere species remain consistent. In addition, mechanistic aspects of confinement have been posed using the electrical double layer theories, and the results can be generalized to other confined systems that are ubiquitous in biology, chemistry, geology and nanotechnology.
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Affiliation(s)
- Xiong Li
- College of Resources and Environment & Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
| | - Chang Zhu
- College of Resources and Environment & Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
| | - Zengqiang Jia
- College of Resources and Environment & Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
| | - Gang Yang
- College of Resources and Environment & Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China.
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13
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Guilbaud P, Berthon L, Louisfrema W, Diat O, Zorz N. Determination of the Structures of Uranyl-Tri-n-butyl-Phosphate Aggregates by Coupling Experimental Results with Molecular Dynamic Simulations. Chemistry 2017; 23:16660-16670. [PMID: 28971546 DOI: 10.1002/chem.201703967] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Indexed: 11/10/2022]
Abstract
The complex structure of a plutonium uranium refining by extraction (PUREX) process organic phase was characterized by combining results from experiments and molecular dynamics simulations. For the first time, the molecular interactions between tri-n-butyl phosphate (TBP) and the extracted solutes, as well as TBP aggregation after the extraction of water and/or uranyl nitrate, were described and analyzed concomitantly. Coupling molecular dynamics simulations with small- and wide-angle X-ray scattering (SWAXS) experiments can lead to simulated organic solutions that are representative of the experimental ones, even for high extractant and solute concentrations. Furthermore, this coupling is well adapted for the interpretation of SWAXS experiments without preliminary hypothesis on the size or shape of aggregates. The results link together previous literature studies obtained for each level of depiction separately (complexation or aggregation). Without uranium, or at low metal concentration, almost no aggregation was observed. At high uranium concentration, organic phases contain small [UO2 (NO3 )2 (TBP)2 ]n polymetallic aggregates (with n=2 to 4), in which the 1:2 U/TBP stoichiometry is preserved.
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Affiliation(s)
- Phillipe Guilbaud
- CEA, Nuclear Energy Division, Research Department, on Mining and Fuel Recycling Processes (SPDS/LILA), BP17171, 30207, Bagnols-sur-Cèze, France
| | - Laurence Berthon
- CEA, Nuclear Energy Division, Research Department, on Mining and Fuel Recycling Processes (SPDS/LILA), BP17171, 30207, Bagnols-sur-Cèze, France
| | - Wilfried Louisfrema
- CEA, Nuclear Energy Division, Research Department, on Mining and Fuel Recycling Processes (SPDS/LILA), BP17171, 30207, Bagnols-sur-Cèze, France
| | - Olivier Diat
- Institut de Chimie Séparative de Marcoule (ICSM/ UMR 5257), CEA/CNRS/UM/ENSCM, BP17171, 30206, Bagnols-sur-Cèze, France
| | - Nicole Zorz
- CEA, Nuclear Energy Division, Research Department, on Mining and Fuel Recycling Processes (SPDS/LILA), BP17171, 30207, Bagnols-sur-Cèze, France
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14
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Kim H, Um W, Kim WS, Chang S. Synthesis of Tributyl Phosphate-Coated Hydroxyapatite for Selective Uranium Removal. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.6b04491] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- HyunJu Kim
- Division
of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), 77 Chongam-ro,
Nam-Gu, Pohang 790-784, Republic of Korea
| | - Wooyong Um
- Division
of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), 77 Chongam-ro,
Nam-Gu, Pohang 790-784, Republic of Korea
- Energy
and Environment Directorate, Pacific Northwest National Laboratory (PNNL), 902 Battelle Boulevard, MSIN P7-54, Richland, Washington 99354, United States
| | - Won-Seok Kim
- Division
of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), 77 Chongam-ro,
Nam-Gu, Pohang 790-784, Republic of Korea
| | - Seeun Chang
- Division
of Advanced Nuclear Engineering, Pohang University of Science and Technology (POSTECH), 77 Chongam-ro,
Nam-Gu, Pohang 790-784, Republic of Korea
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15
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Zhao HB, Zheng M, Schreckenbach G, Pan QJ. Interfacial Interaction of Titania Nanoparticles and Ligated Uranyl Species: A Relativistic DFT Investigation. Inorg Chem 2017; 56:2763-2776. [DOI: 10.1021/acs.inorgchem.6b02927] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hong-Bo Zhao
- Key Laboratory of
Functional Inorganic Material Chemistry of Education Ministry, School
of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
| | - Ming Zheng
- Key Laboratory of
Functional Inorganic Material Chemistry of Education Ministry, School
of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg R3T 2N2, MB, Canada
| | - Qing-Jiang Pan
- Key Laboratory of
Functional Inorganic Material Chemistry of Education Ministry, School
of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China
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16
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Arima T, Idemitsu K, Inagaki Y, Kawamura K, Tachi Y, Yotsuji K. Diffusion and adsorption of uranyl ion in clays: Molecular dynamics study. PROGRESS IN NUCLEAR ENERGY 2016. [DOI: 10.1016/j.pnucene.2016.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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van Veelen A, Bargar JR, Law GTW, Brown GE, Wogelius RA. Uranium Immobilization and Nanofilm Formation on Magnesium-Rich Minerals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:3435-3443. [PMID: 26990311 DOI: 10.1021/acs.est.5b06041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Polarization-dependent grazing incidence X-ray absorption spectroscopy (XAS) measurements were completed on oriented single crystals of magnesite [MgCO3] and brucite [Mg(OH)2] reacted with aqueous uranyl chloride above and below the solubility boundaries of schoepite (500, 50, and 5 ppm) at pH 8.3 and at ambient (PCO2 = 10(-3.5)) or reduced partial pressures of carbon dioxide (PCO2 = 10(-4.5)). X-ray absorption near edge structure (XANES) spectra show a striking polarization dependence (χ = 0° and 90° relative to the polarization plane of the incident beam) and consistently demonstrated that the uranyl molecule was preferentially oriented with its Oaxial═U(VI)═Oaxial linkage at high angles (60-80°) to both magnesite (101̅4) and brucite (0001). Extended X-ray absorption fine structure (EXAFS) analysis shows that the "effective" number of U(VI) axial oxygens is the most strongly affected fitting parameter as a function of polarization. Furthermore, axial tilt in the surface thin films (thickness ∼ 21 Å) is correlated with surface roughness [σ]. Our results show that hydrated uranyl(-carbonate) complexes polymerize on all of our experimental surfaces and that this process is controlled by surface hydroxylation. These results provide new insights into the bonding configuration expected for uranyl complexes on the environmentally significant carbonate and hydroxide mineral surfaces.
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Affiliation(s)
| | - John R Bargar
- Department of Photon Science and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | | | - Gordon E Brown
- Department of Photon Science and Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Surface and Aqueous Geochemistry Group, Department of Geological Sciences, School of Earth, Energy, and Environmental Sciences, Stanford University , Stanford, California 94305-2115, United States
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18
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Tirler AO, Hofer TS. The structural influence of Ca(2+) counter-ions on uranyl(VI) tricarbonate in aqueous solution. Dalton Trans 2016; 45:4983-8. [PMID: 26932659 DOI: 10.1039/c5dt04718h] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The presented study elucidates the influence of calcium(II) counter-ions on the structure of the environmentally relevant uranyl tricarbonates using hybrid quantum mechanical/molecular mechanical (QM/MM) MD simulations. Since experimental investigations may be subject to limitations in detecting the presence of counter-ions in solution, the present study is of importance to obtain a profound understanding of the effects counter-ions may have on coordination complexes. It can be concluded from the obtained simulation data that two calcium(II) ions are essential for stabilizing the experimentally observed uranyl tricarbonate complex in aqueous solution. Including only one calcium(II) ion in the coordination sphere was found to be insufficient to form a six-fold equatorial coordination of carbonates, but a five-fold coordination is adopted similar to the counter-ion free case in aqueous solution reported in a previous study.
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Affiliation(s)
- Andreas O Tirler
- Theoretical Chemistry Division Institute of General, Inorganic and Theoretical Chemistry University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria.
| | - Thomas S Hofer
- Theoretical Chemistry Division Institute of General, Inorganic and Theoretical Chemistry University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria.
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19
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Debbarma R, Malani A. Comparative Study of Water Adsorption on a H(+) and K(+) Ion Exposed Mica Surface: Monte Carlo Simulation Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:1034-1046. [PMID: 26727708 DOI: 10.1021/acs.langmuir.5b04131] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Clay minerals are used in variety of applications ranging from composites to electronic devices. For their efficient use in such areas, understanding the effect of surface-active agents on interfacial properties is essential. We investigated the role of surface ions in the adsorption of water molecules by using a muscovite mica surface populated with two different, H(+) and K(+), surface ions. A series of grand canonical Monte Carlo (GCMC) simulations at various relative vapor pressures (p/p0) were performed to obtain the water structure and adsorption isotherm on the H(+)-exposed mica (H-mica) surface. The obtained results were compared to the recent simulation data of water adsorption on the K(+)-exposed mica (K-mica) surface reported by Malani and Ayyappa (Malani, A.; Ayappa, K. G. J. Phys. Chem. B 2009, 113, 1058-1067). Water molecules formed two prominent layers adjacent to the H-mica surface, whereas molecular layering was observed adjacent to the K-mica surface. The adsorption isotherm of water on the K-mica surface was characterized by three stages that corresponded to rapid adsorption in the initial regime below p/p0 = 0.1, followed by a linear development regime for p/p0 = 0.1-0.7 and rapid film thickening for p/p0 ≥ 0.7, whereas only latter two regimes were observed in the H-mica system. In addition, the film thickness of adsorbed water molecules for p/p0 < 0.7 was lower as compared to that for the K-mica surface and comparable beyond. The film thickness obtained from the MC simulations was in excellent agreement with the interferometry experimental data of Balmer et al. (Balmer, T. E.; Christenson, H. K.; Spencer, N. D.; Heuberger, M. Langmuir 2008, 24, 1566-1569). It was observed that the hydration behaviors of the two ions were completely different and depended on the size of their hydration shell and their ability to form hydrogen bonds. The behavior of water adsorption between these two cases was illustrated using the water density distribution, orientational distributions, hydrogen bonding, and isosteric heats of adsorption.
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Affiliation(s)
- Rousan Debbarma
- Department of Chemical Engineering, Indian Institute of Technology Bombay , Mumbai, India
| | - Ateeque Malani
- Department of Chemical Engineering, Indian Institute of Technology Bombay , Mumbai, India
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20
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Ou X, Zhuang Z, Li J, Huang F, Lin Z. Mechanism of adsorption affinity and capacity of Mg(OH)2 to uranyl revealed by molecular dynamics simulation. RSC Adv 2016. [DOI: 10.1039/c6ra00384b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The redistribution of surface OH groups results in a negative charge site which facilitates the uranyl adsorption.
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Affiliation(s)
- Xinwen Ou
- Key Laboratory of Design and Assembly of Functional Nanostructures
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou
- China
| | - Zanyong Zhuang
- Key Laboratory of Design and Assembly of Functional Nanostructures
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou
- China
| | - Jingyuan Li
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety
- Institute of High Energy Physics
- Chinese Academy of Sciences
- Beijing 100049
- China
| | - Feng Huang
- State Key Laboratory of Optoelectronic Materials and Technologies
- School of Physics and Engineering
- Sun Yat-Sen University
- Guangzhou 510275
- China
| | - Zhang Lin
- Key Laboratory of Design and Assembly of Functional Nanostructures
- Fujian Institute of Research on the Structure of Matter
- Chinese Academy of Sciences
- Fuzhou
- China
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21
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Li X, Li H, Yang G. Promoting the Adsorption of Metal Ions on Kaolinite by Defect Sites: A Molecular Dynamics Study. Sci Rep 2015; 5:14377. [PMID: 26403873 PMCID: PMC4585903 DOI: 10.1038/srep14377] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 08/25/2015] [Indexed: 11/26/2022] Open
Abstract
Defect sites exist abundantly in minerals and play a crucial role for a variety of important processes. Here molecular dynamics simulations are used to comprehensively investigate the adsorption behaviors, stabilities and mechanisms of metal ions on defective minerals, considering different ionic concentrations, defect sizes and contents. Outer-sphere adsorbed Pb2+ ions predominate for all models (regular and defective), while inner-sphere Na+ ions, which exist sporadically only at concentrated solutions for regular models, govern the adsorption for all defective models. Adsorption quantities and stabilities of metal ions on kaolinite are fundamentally promoted by defect sites, thus explaining the experimental observations. Defect sites improve the stabilities of both inner- and outer-sphere adsorption, and (quasi) inner-sphere Pb2+ ions emerge only at defect sites that reinforce the interactions. Adsorption configurations are greatly altered by defect sites but respond weakly by changing defect sizes or contents. Both adsorption quantities and stabilities are enhanced by increasing defect sizes or contents, while ionic concentrations mainly affect adsorption quantities. We also find that adsorption of metal ions and anions can be promoted by each other and proceeds in a collaborative mechanism. Results thus obtained are beneficial to comprehend related processes for all types of minerals.
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Affiliation(s)
- Xiong Li
- College of Resources and Environment &Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
| | - Hang Li
- College of Resources and Environment &Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
| | - Gang Yang
- College of Resources and Environment &Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing 400715, China
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22
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Zaunbrecher LK, Cygan RT, Elliott WC. Molecular Models of Cesium and Rubidium Adsorption on Weathered Micaceous Minerals. J Phys Chem A 2015; 119:5691-700. [DOI: 10.1021/jp512824k] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Laura K. Zaunbrecher
- Department
of Geosciences, Georgia State University, Atlanta, Georgia 30302-3965, United States
| | - Randall T. Cygan
- Geochemistry
Department, Sandia National Laboratories, Albuquerque, New Mexico 87185-0754, United States
| | - W. Crawford Elliott
- Department
of Geosciences, Georgia State University, Atlanta, Georgia 30302-3965, United States
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23
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Zhang N, Liu X, Li C, Liu C. Effect of electrolyte concentration on uranium species adsorption: a molecular dynamics study. Inorg Chem Front 2015. [DOI: 10.1039/c4qi00141a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A threshold electrolyte concentration may cause a dramatic alteration in the uranyl species adsorption relative to lower electrolyte concentrations.
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Affiliation(s)
- Na Zhang
- Beijing National Laboratory for Molecular Sciences
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Xiaoyu Liu
- Beijing National Laboratory for Molecular Sciences
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Chun Li
- Beijing National Laboratory for Molecular Sciences
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
| | - Chunli Liu
- Beijing National Laboratory for Molecular Sciences
- Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science
- College of Chemistry and Molecular Engineering
- Peking University
- Beijing 100871
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24
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Sprynskyy M, Kowalkowski T, Tutu H, Cukrowska EM, Buszewski B. Ionic liquid modified diatomite as a new effective adsorbent for uranium ions removal from aqueous solution. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2014.10.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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25
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Tirler AO, Hofer TS. Structure and Dynamics of the Uranyl Tricarbonate Complex in Aqueous Solution: Insights from Quantum Mechanical Charge Field Molecular Dynamics. J Phys Chem B 2014; 118:12938-51. [DOI: 10.1021/jp503171g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Andreas O. Tirler
- Theoretical
Chemistry Division,
Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Thomas S. Hofer
- Theoretical
Chemistry Division,
Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
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26
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Lou Z, Liu H, Zhang Y, Meng Y, Zeng Q, Shi J, Yang M. A density functional theory study of the hydration of calcium ions confined in the interlayer space of montmorillonites. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2014. [DOI: 10.1142/s021963361450028x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The structures of Ca2+hydrates in the interlayer space of montmorillonites (MMT) were studied by periodic density functional theory (DFT) calculations under the GGA/PBE approximation. Affected by the internal surfaces, which are rich of negative charge, the Ca2+hydration exhibits different behaviors from that in gas phase. The Ca2+is located at the six-oxygen-ring (SOR) on the internal surface in dry MMT, while the incoming water molecules bind with the Ca2+, the O atoms on surface, and/or with each other. The water molecules have a tendency of forming a hydrogen bond (HB) network that connects the upper and lower surfaces. Attracted by surrounding water molecules, the Ca2+gradually moves outward with increasing number of water molecules. Moreover, the hydration energy (EH) of Ca2+is determined not only by the interaction between Ca2+and H2O , but also by that among Ca2+, H2O and the surfaces. As a result, the EHhas only small changes for additional incoming water molecules, in contrast to the great and monotonic decrease in gas phase.
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Affiliation(s)
- Zhaoyang Lou
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, School of Petroleum Engineering, Southwest Petroleum University, Chengdu 610500, P. R. China
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - Houbin Liu
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, School of Petroleum Engineering, Southwest Petroleum University, Chengdu 610500, P. R. China
| | - Yao Zhang
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, School of Petroleum Engineering, Southwest Petroleum University, Chengdu 610500, P. R. China
| | - Yingfeng Meng
- State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, School of Petroleum Engineering, Southwest Petroleum University, Chengdu 610500, P. R. China
| | - Qun Zeng
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - Jing Shi
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
| | - Mingli Yang
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, P. R. China
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27
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Kerisit S, Liu C. Molecular dynamics simulations of uranyl and uranyl carbonate adsorption at aluminosilicate surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:3899-3907. [PMID: 24580048 DOI: 10.1021/es405387c] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Adsorption at mineral surfaces is a critical factor controlling the mobility of uranium(VI) in aqueous environments. Therefore, molecular dynamics (MD) simulations were performed to investigate uranyl(VI) adsorption onto two neutral aluminosilicate surfaces, namely, the orthoclase (001) surface and the octahedral aluminum sheet of the kaolinite (001) surface. Although uranyl preferentially adsorbs as a bidentate inner-sphere complex on both surfaces, the free energy of adsorption on the orthoclase surface (-15 kcal mol(-1)) is significantly more favorable than that at the kaolinite surface (-3 kcal mol(-1)), which is attributed to differences in surface functional groups and the ability of the orthoclase surface to release a surface potassium ion upon uranyl adsorption. The structures of the adsorbed complexes compare favorably with X-ray absorption spectroscopy results. Simulations of the adsorption of uranyl complexes with up to three carbonate ligands revealed that uranyl complexes coordinated to up to two carbonate ions are stable on the orthoclase surface whereas uranyl carbonate surface complexes are unfavored at the kaolinite surface. Combining the MD-derived equilibrium adsorption constants for orthoclase with aqueous equilibrium constants for uranyl carbonate species indicates the presence of adsorbed uranium complexes with one or two carbonates under alkaline conditions, in support of current uranium(VI) surface complexation models.
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Affiliation(s)
- Sebastien Kerisit
- Physical Sciences Division, Pacific Northwest National Laboratory , Richland, Washington 99352, United States
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28
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Teich-McGoldrick SL, Greathouse JA, Cygan RT. Molecular dynamics simulations of uranyl adsorption and structure on the basal surface of muscovite. MOLECULAR SIMULATION 2014. [DOI: 10.1080/08927022.2013.838675] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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29
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Tirler AO, Weiss AKH, Hofer TS. A Comparative Quantum Mechanical Charge Field Study of Uranyl Mono- and Dicarbonate Species in Aqueous Solution. J Phys Chem B 2013; 117:16174-87. [DOI: 10.1021/jp407179s] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Andreas O. Tirler
- Theoretical Chemistry Division, Institute
of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Austria
| | - Alexander K. H. Weiss
- Theoretical Chemistry Division, Institute
of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Austria
| | - Thomas S. Hofer
- Theoretical Chemistry Division, Institute
of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innrain
80-82, A-6020 Innsbruck, Austria
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30
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Yang W, Zaoui A. Behind adhesion of uranyl onto montmorillonite surface: a molecular dynamics study. JOURNAL OF HAZARDOUS MATERIALS 2013; 261:224-234. [PMID: 23933290 DOI: 10.1016/j.jhazmat.2013.07.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 05/13/2013] [Accepted: 07/12/2013] [Indexed: 06/02/2023]
Abstract
We have performed molecular dynamics simulations to investigate the adsorption of radionuclide elements species onto substituted Montmorillonite (001) surface in the presence of different counterions. The structure and the dynamics of uranyl ion as well as its aquo, chloride ion, and carbonate complexes are analyzed. In addition, we have studied the surface energy between layered Montmorillonite sheets and the work of adhesion between radionuclide and charged Montmorillonite. The clay model used here is a Wyoming-type Montmorillonite with 0.75e negative charge per unit cell resulting from substitutions in Octahedral and Tetrahedral sheets. The system model was constructed based on CLAYFF force field potential model. To evaluate the thermodynamic work of adhesion, each surface and clay layer regions are converted to a thin film model. One and two species of radionuclide elements (UO2(H2O)5,UO2CO3(H2O)5, and UO2Cl2(H2O)5) were deposited near the clay surface in a pseudo-two-dimensional periodic cell. Analysis shows that the uranyl ion structure is preserved with two axial oxygen atoms detected at 1.8Å. Radial distribution functions results indicate that average UOw distances are 2.45-2.61Å, and 2.29-2.40Å for UOc distance. Average UCl distances are 2.78-3.08Å, which is relatively larger than that of Uranium atom-Oxygen atom because of electrostatic factors.
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Affiliation(s)
- W Yang
- LGCgE (EA 4515), University of Lille1, Polytech'Lille. Cité Scientifique Avenue Paul Langevin, 59655 Villeneuve d'Ascq, France
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Bohinc K, Reščič J, Dufreche JF, Lue L. Recycling of Uranyl from Contaminated Water. J Phys Chem B 2013; 117:10846-51. [DOI: 10.1021/jp404822f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Klemen Bohinc
- Faculty
of Health Sciences, University of Ljubljana, Zdravstvena 5, SI-1000 Ljubljana, Slovenia
| | - Jurij Reščič
- Faculty
of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva
5, SI-1000 Ljubljana, Slovenia
| | - Jean-Francois Dufreche
- Institut
de Chimie Separative de Marcoule, Universite de Montpellier, 30207 Bagnols sur Ceze
Cedex, France
| | - Leo Lue
- Department
of Chemical and Process Engineering, James Weir Building, University of Strathclyde, 75 Montrose Street, Glasgow G1 1XJ, United Kingdom
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Wogelius RA. Adsorption and co-precipitation reactions at the mineral-fluid interface: natural and anthropogenic processes. CRYSTAL RESEARCH AND TECHNOLOGY 2013. [DOI: 10.1002/crat.201200712] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Roy A. Wogelius
- University of Manchester, School of Earth, Atmospheric, and Environmental Sciences and Williamson Centre for Molecular Environmental Science Oxford Road; Manchester M13 9PL U.K
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33
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Kerisit S, Liu C. Structure, Kinetics, and Thermodynamics of the Aqueous Uranyl(VI) Cation. J Phys Chem A 2013; 117:6421-32. [DOI: 10.1021/jp404594p] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Sebastien Kerisit
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington
99352, United States
| | - Chongxuan Liu
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington
99352, United States
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Zhao Q, Burns SE. Modeling sorption and diffusion of organic sorbate in hexadecyltrimethylammonium-modified clay nanopores - a molecular dynamics simulation study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:2769-2776. [PMID: 23413980 DOI: 10.1021/es3045482] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Organoclays are highly sorptive engineered materials that can be used as amendments in barrier systems or geosynthetic liners. The performance of confining and isolating the nonpolar organic contaminants by those barrier/lining systems is essentially controlled by the process of organic contaminant mass transport in nanopores of organoclays. In this article, we use molecular dynamics (MD) simulations to study the sorption and diffusion of organic sorbates in interlayers of sodium montmorillonite and hexadecyltrimethylammonium (HDTMA(+))-modified montmorillonite clays. Simulated system consisted of the clay framework, interlayer organic cation, water, and organic sorbate. Their interactions were addressed by the combined force field of ClayFF, constant-valence force field, and SPC water model. Simulation results indicated that in HDTMA coated clay nanopores, diffusion of nonpolar species benzene was slowed because they were subjected to influence of both the pore wall and the HDTMA surfactant. This suggested the nonpolar organic compound diffusion in organophilic clays can be affected by molecular size of diffusive species, clay pore size, and organic surfactant loading. Additionally, a model that connected the diffusion rate of organic compounds in the bulk organoclay matrix with macropores and nanopores was established. The impact of intercalated organic cations on the diffusion dominated mass transport of organic compounds yielded insight into the prediction of the apparent diffusion behavior of organic compounds in organic-modified clays.
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Affiliation(s)
- Qian Zhao
- School of Civil and Environmental Engineering, 790 Atlantic Drive, N.W., Georgia Institute of Technology, Atlanta, Georgia 30332-0355, USA
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35
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Geckeis H, Lützenkirchen J, Polly R, Rabung T, Schmidt M. Mineral–Water Interface Reactions of Actinides. Chem Rev 2013; 113:1016-62. [DOI: 10.1021/cr300370h] [Citation(s) in RCA: 223] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Horst Geckeis
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Johannes Lützenkirchen
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Robert Polly
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Thomas Rabung
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
| | - Moritz Schmidt
- Karlsruhe Institute of Technology (KIT), Institute for Nuclear Waste Disposal
(INE), Karlsruhe, P.O.Box 3640, D-76021 Karlsruhe, Germany
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36
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Liu XY, Wang LH, Zheng Z, Kang ML, Li C, Liu CL. Molecular dynamics simulation of the diffusion of uranium species in clay pores. JOURNAL OF HAZARDOUS MATERIALS 2013; 244-245:21-28. [PMID: 23246937 DOI: 10.1016/j.jhazmat.2012.11.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 11/01/2012] [Accepted: 11/13/2012] [Indexed: 06/01/2023]
Abstract
Molecular dynamics simulations were carried out to investigate the diffusive behavior of aqueous uranium species in montmorillonite pores. Three uranium species (UO(2)(2+), UO(2)CO(3), UO(2)(CO(3))(2)(2-)) were confirmed in both the adsorbed and diffuse layers. UO(2)(CO(3))(3)(4-) was neglected in the subsequent analysis due to its scare occurrence. The species-based diffusion coefficients in montmorillonite pores were then calculated, and compared with the water mobility and their diffusivity in aqueous solution/feldspar nanosized fractures. Three factors were considered that affected the diffusive behavior of the uranium species: the mobility of water, the self-diffusion coefficient of the aqueous species, and the electrostatic forces between the negatively charged surface and charged molecules. The mobility of U species in the adsorbed layer decreased in the following sequence: UO(2)(2+)>UO(2)CO(3)>UO(2)(CO(3))(2)(2-). In the diffuse layer, we obtained the highest diffusion coefficient for UO(2)(CO(3))(2)(2-) with the value of 5.48×10(-10) m(2) s(-1), which was faster than UO(2)(2+). For these two charged species, the influence of electrostatic forces on the diffusion of solutes in the diffuse layer is overwhelming, whereas the influence of self-diffusion and water mobility is minor. Our study demonstrated that the negatively charged uranyl carbonate complex must be addressed in the safety assessment of potential radioactive waste disposal systems.
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Affiliation(s)
- Xiao-yu Liu
- Beijing National Laboratory for Molecular Sciences, Radiochemistry and Radiation Chemistry Key Laboratory for Fundamental Science, College of Chemistry Molecular Engineering, Peking University, Beijing 100871, China
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Doudou S, Vaughan DJ, Livens FR, Burton NA. Atomistic simulations of calcium uranyl(VI) carbonate adsorption on calcite and stepped-calcite surfaces. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:7587-7594. [PMID: 22642750 DOI: 10.1021/es300034k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Adsorption of actinyl ions onto mineral surfaces is one of the main mechanisms that control the migration of these ions in environmental systems. Here, we present computational classical molecular dynamics (MD) simulations to investigate the behavior of U(VI) in contact with different calcite surfaces. The calcium-uranyl-carbonate [Ca(2)UO(2)(CO(3))(3)] species is shown to display both inner- and outer-sphere adsorption to the flat {101̅4} and the stepped {314̅8} and {31̅2̅16} planes of calcite. Free energy calculations, using the umbrella sampling method, are employed to simulate adsorption paths of the same uranyl species on the different calcite surfaces under aqueous condition. Outer-sphere adsorption is found to dominate over inner-sphere adsorption because of the high free energy barrier of removing a uranyl-carbonate interaction and replacing it with a new uranyl-surface interaction. An important binding mode is proposed involving a single vicinal water monolayer between the surface and the sorbed complex. From the free energy profiles of the different calcite surfaces, the uranyl complex was also found to adsorb preferentially on the acute-stepped {314̅8} face of calcite, in agreement with experiment.
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Affiliation(s)
- Slimane Doudou
- School of Chemistry, University of Manchester, Manchester, M13 9PL, UK
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39
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Zhu R, Hu W, You Z, Ge F, Tian K. Molecular dynamics simulation of TCDD adsorption on organo-montmorillonite. J Colloid Interface Sci 2012; 377:328-33. [DOI: 10.1016/j.jcis.2012.03.034] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 03/09/2012] [Accepted: 03/14/2012] [Indexed: 10/28/2022]
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40
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Zhao Q, Burns SE. Molecular dynamics simulation of secondary sorption behavior of montmorillonite modified by single chain quaternary ammonium cations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:3999-4007. [PMID: 22364194 DOI: 10.1021/es202115v] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Organoclays synthesized from single chain quaternary ammonium cations (QAC) ((CH(3))(3)NR(+)) exhibit different mechanisms for the sorption of nonpolar organic compounds as the length of the carbon chain is increased. The interaction between a nonpolar sorbate and an organoclay intercalated with small QACs has been demonstrated to be surface adsorption, while partitioning is the dominant mechanism in clays intercalated with long chain surfactants. This study presents the results of a molecular dynamics (MD) simulation performed to examine the sorption mechanisms of benzene in the interlayer of three organoclays with chain lengths ranging from 1 to 16 carbons: tetramethylammonium (TMA) clay; decyltrimethylammonium (DTMA) clay; and hexadecyltrimethylammonium (HDTMA) clay. The basis of the overall simulation was a combined force field of ClayFF and CVFF. In the simulations, organic cations were intercalated and benzene molecules were introduced to the interlayer, followed by whole system NPT and NVT time integration. Trajectories of all the species were recorded after the system reached equilibrium and subsequently analyzed. Simulation results confirmed that the arrangement of the surfactants controlled the sorption mechanism of organoclays. Benzene molecules were observed to interact directly with the clay surface in the presence of TMA cations, but tended to interact with the aliphatic chain of the HDTMA cation in the interlayer. The simulation provided insight into the nature of the adsorption/partitioning mechanisms in organoclays, and explained experimental observations of decreased versus increased uptake capacities as a function of increasing total organic carbon (TOC) for TMA clay and HDTMA clay, respectively. The transition of sorption mechanisms was also quantified with simulation of DTMA clay, with a chain length between that of TMA and HDTMA. Furthermore, this study suggested that at the molecular level, the controlling factor for the ultimate sorption capacity is available surface sites in the case of TMA clay, and density of aliphatic chains within the interlayer space for HDTMA clay.
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Affiliation(s)
- Qian Zhao
- School of Civil and Environmental Engineering, NW Georgia Institute of Technology, Atlanta, Georgia 30332-0355, United States
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41
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Kerisit S, Liu C. Diffusion and adsorption of uranyl carbonate species in nanosized mineral fractures. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:1632-1640. [PMID: 22206276 DOI: 10.1021/es2027696] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Atomistic simulations were performed to study the diffusion and adsorption of Ca(2)UO(2)(CO3)3 and of some of its constituent species, i.e., UO(2)2+, CO(3)2–, and UO(2)CO3, in feldspar nanosized fractures. Feldspar is important to uranium remediation efforts at the U.S. Department of Energy Hanford site as it has been found in recent studies to host contaminants within its intragrain fractures. In addition, uranyl carbonate species are known to dominate U(VI) speciation in conditions relevant to the Hanford site. Molecular dynamics (MD) simulations showed that the presence of the feldspar surface diminishes the diffusion coefficients of all of the species considered in this work and that the diffusion coefficients do not reach their bulk aqueous solution values in the center of a 2.5 nm fracture. Moreover, the MD simulations showed that the rate of decrease in the diffusion coefficients with decreasing distance from the surface is greater for larger adsorbing species. Free energy profiles of the same species adsorbing on the feldspar surface revealed a large favorable free energy of adsorption for UO(2)2+ and UO(2)CO3, which are able to adsorb to the surface with their uranium atom directly bonded to a surface hydroxyl oxygen, whereas adsorption of CO(3)2– and Ca(2)UO(2)(CO3)3, which attach to the surface via hydrogen bonding from a surface hydroxyl group to a carbonate oxygen, was calculated to be either only slightly favorable or unfavorable.
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Affiliation(s)
- Sebastien Kerisit
- Pacific Northwest National Laboratory, Chemical and Materials Sciences Division, Richland, Washington 99352, United States.
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42
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Zeitler TR, Greathouse JA, Cygan RT. Effects of thermodynamic ensembles and mineral surfaces on interfacial water structure. Phys Chem Chem Phys 2012; 14:1728-34. [DOI: 10.1039/c2cp22593j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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43
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Bühl M, Wipff G. Insights into Uranyl Chemistry from Molecular Dynamics Simulations. Chemphyschem 2011; 12:3095-105. [DOI: 10.1002/cphc.201100458] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 07/28/2011] [Indexed: 11/10/2022]
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44
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Affiliation(s)
- Alberto Striolo
- School of Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK 73019, U.S.A
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45
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Boily JF, Rosso KM. Crystallographic controls on uranyl binding at the quartz/water interface. Phys Chem Chem Phys 2011; 13:7845-51. [DOI: 10.1039/c0cp01406k] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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46
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Doudou S, Arumugam K, Vaughan DJ, Livens FR, Burton NA. Investigation of ligand exchange reactions in aqueous uranyl carbonate complexes using computational approaches. Phys Chem Chem Phys 2011; 13:11402-11. [DOI: 10.1039/c1cp20617f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Abstract
Abstract
We overview quantum mechanical simulations that model the adsorption of actinide ions at solvated mineral surfaces. Pertinent examples illustrate the status of this emerging field of computational chemistry. In particular, we describe our own studies on uranyl adsorption on kaolinite. Already the few available results, from applications of density functional methods to cluster models or periodic slab models, show that such calculations are a useful complement to experimental investigations. Detailed information at the atomic level from accurate electronic structure calculations on well defined model systems helps to refine current interpretations of the chemical nature of uranyl adsorption species and to discover new features of these interface systems. Results from quantum mechanical simulations also provide a valuable reference for future experimental investigations.
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Rotenberg B, Marry V, Malikova N, Turq P. Molecular simulation of aqueous solutions at clay surfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:284114. [PMID: 21399286 DOI: 10.1088/0953-8984/22/28/284114] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report a molecular simulation study of aqueous solutions at montmorillonite clay surfaces. Unlike most previous studies, ours does not focus on the interlayer nanopores, but looks at both kinds of external surfaces of clay particles: basal surfaces along the clay layers, and lateral surfaces through which interlayer and larger interparticle pores are linked. We present results on structural, dynamic and thermodynamic properties and phenomena, including hydration complexes of ions, H bonding networks, modification of the water dynamics with respect to the bulk, and the role of water in the cation exchange between interlayer and interparticle pores.
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Affiliation(s)
- B Rotenberg
- UPMC Université, Paris-06 and CNRS, PECSA, UMR 7195, F-75005, Paris, France.
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49
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Anderson RL, Greenwell HC, Suter JL, Coveney PV, Thyveetil MA. Determining materials properties of natural composites using molecular simulation. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b909119j] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Jardat M, Dufrêche JF, Marry V, Rotenberg B, Turq P. Salt exclusion in charged porous media: a coarse-graining strategy in the case of montmorillonite clays. Phys Chem Chem Phys 2009; 11:2023-33. [DOI: 10.1039/b818055e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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