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Xie T, Qian T, Lian B, Chen C, Liang P, Liu X, Li T, Wang T, Chen K, Zhang A, Zhu J. Research on leaching behavior of uranium from a uranium tailing and its adsorption behavior in geotechnical media. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 353:120207. [PMID: 38281428 DOI: 10.1016/j.jenvman.2024.120207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/05/2023] [Accepted: 01/20/2024] [Indexed: 01/30/2024]
Abstract
The release of uranium from uranium tailings into the aqueous environment is a complex process controlled by a series of interacting geochemical reactions. In this paper, uranium tailings from a uranium tailings pond in southern China were collected at different depths by means of borehole sampling and mixed to analyze the fugacity state of U. Static leaching experiments of U at different pH, oxidant concentration and solid-to-liquid ratios and dynamic leaching experiments of U at different pH were carried out, and the adsorption and desorption behaviour of U in five representative stratigraphic media were investigated. The results show that U is mainly present in the residue state in uranium tailings, that U release is strong in the lower pH range, that the leached U is mainly in the form of U(VI), mainly from the water-soluble, Fe/Mn oxides and exchangeable fraction of uranium tailings, and that the reduction in U leaching at higher pH is mainly due to the combined effect of precipitation formation and larger particle size of platelets in uranium tailings. Experiments with different oxidant concentrations and solid-liquid ratios showed that the oxygen-enriched state and low solid-liquid ratios were favorable for the leaching of U from uranium tailings. Adsorption and desorption experiments show that U is weakly adsorbed in representative strata, reversibly adsorbed, and that U is highly migratory in groundwater. The present research results have important guiding significance for the management of existing uranium tailings ponds and the control of U migration in groundwater, which is conducive to ensuring the long-term safety, stability and sustainability of uranium mining sites.
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Affiliation(s)
- Tian Xie
- College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, 030600, China; China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Tianwei Qian
- College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, 030600, China.
| | - Bing Lian
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Chao Chen
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Pengliang Liang
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Xiaona Liu
- College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, 030600, China
| | - Ting Li
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Ting Wang
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Ke Chen
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Aiming Zhang
- China Institute for Radiation Protection, Taiyuan, 030006, China
| | - Jun Zhu
- China Institute for Radiation Protection, Taiyuan, 030006, China; School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, China.
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Li J, Nie Z, Fan Z, Li C, Liu B, Hua Q, Hou C. Biochemical Fulvic Acid Modification for Phosphate Crystal Inhibition in Water and Fertilizer Integration. MATERIALS 2022; 15:ma15031174. [PMID: 35161118 PMCID: PMC8840660 DOI: 10.3390/ma15031174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/23/2022] [Accepted: 01/24/2022] [Indexed: 02/04/2023]
Abstract
Biochemical fulvic acid (BFA), produced by organic wastes composting, is the complex organic matter with various functional groups. A novel modified biochemical fulvic acid (MBFA) which possessed stronger chelating ability had been synthesized by the grafting copolymerization of BFA and acrylic acid (AA). Results showed that MBFA effectively inhibited the crystallization of calcium phosphate and increased the concentration of phosphate in water solution. The optimum reaction conditions optimized by Box–Behnken design and response surface methodology were reaction temperature 69.24 °C, the mass of monomer to fulvic acid ratio 0.713, the initiator dosage 19.78%, and phosphate crystal-inhibition extent was 96.89%. IR spectra demonstrated AA was grafted onto BFA. XRD data and SEM images appeared the formation and growth of calcium phosphate crystals was effectively inhibited by MBFA.
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Affiliation(s)
- Jianyun Li
- School of Civil Engineering and Architecture, Zhengzhou University of Aeronautics, Zhengzhou 450046, China; (J.L.); (C.L.)
| | - Zihan Nie
- School of Chemical Engineering, National Center for Research and Popularization on Calcium, Magnesium, Phosphate & Compound Fertilizer Technology, Zhengzhou University, Zhengzhou 450001, China; (B.L.); (Q.H.); (C.H.)
- Correspondence:
| | - Zhao Fan
- School of Environmental Economics, Henan Finance University, Zhengzhou 450046, China;
| | - Chunguang Li
- School of Civil Engineering and Architecture, Zhengzhou University of Aeronautics, Zhengzhou 450046, China; (J.L.); (C.L.)
| | - Bingbing Liu
- School of Chemical Engineering, National Center for Research and Popularization on Calcium, Magnesium, Phosphate & Compound Fertilizer Technology, Zhengzhou University, Zhengzhou 450001, China; (B.L.); (Q.H.); (C.H.)
| | - Quanxian Hua
- School of Chemical Engineering, National Center for Research and Popularization on Calcium, Magnesium, Phosphate & Compound Fertilizer Technology, Zhengzhou University, Zhengzhou 450001, China; (B.L.); (Q.H.); (C.H.)
| | - Cuihong Hou
- School of Chemical Engineering, National Center for Research and Popularization on Calcium, Magnesium, Phosphate & Compound Fertilizer Technology, Zhengzhou University, Zhengzhou 450001, China; (B.L.); (Q.H.); (C.H.)
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Liu C, Xu Q, Xu Y, Wang B, Long H, Fang S, Zhou D. Characterization of adsorption behaviors of U(VI) on bentonite colloids: batch experiments, kinetic evaluation and thermodynamic analysis. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-021-08123-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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You N, Chen S, Wang Y, Fan HT, Sun LN, Sun T. In situ sampling of tetracycline antibiotics in culture wastewater using diffusive gradients in thin films equipped with graphene nanoplatelets. ENVIRONMENTAL RESEARCH 2020; 191:110089. [PMID: 32861726 DOI: 10.1016/j.envres.2020.110089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 08/08/2020] [Accepted: 08/08/2020] [Indexed: 06/11/2023]
Abstract
A device of graphene nanoplatelet-based diffusion gradients in thin-films (G-DGT) was developed for in situ sampling of tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC) in aquatic environment. The accumulation of antibiotics in a synthetic solution by the proposed G-DGT was consistent with the theoretical curves predicted by the DGT equation. The values of the detection and quantification limits of G-DGT using high-performance liquid chromatography over the deployment time of 7 days were at the level of μg L-1 for the three antibiotics. The performance of the proposed G-DGT was unaffected by pH (3-9) and ionic strength (0.001-0.7 mol L-1 NaNO3). Fulvic acid did not significantly interfere with the performance of the proposed G-DGT device when the mass ratios between the three antibiotics and fulvic acid were within the range of 1:10-1:100. Humic acid had a significant effect on the performance of the proposed G-DGT for the sampling of the three antibiotics due to strong complexation and coprecipitation between the antibiotics and humic acid. The proposed G-DGT was used for the in situ sampling in spiked freshwaters and livestock culture wastewater and exhibited good precision and accuracy without notable interference from the matrices.
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Affiliation(s)
- Nan You
- College of Chemistry Chemical Engineering and Environmental Engineering, Liaoning Shihua University, Fushun, 113001, Liaoning, China
| | - Su Chen
- Key Lab of Eco-restoration of Regional Contaminated Environment (Shenyang University), Ministry of Education, Shenyang, 110044, China
| | - Yun Wang
- College of Sciences, Northeastern University, Shenyang, 110004, China
| | - Hong-Tao Fan
- College of Chemistry Chemical Engineering and Environmental Engineering, Liaoning Shihua University, Fushun, 113001, Liaoning, China.
| | - Li-Na Sun
- Key Lab of Eco-restoration of Regional Contaminated Environment (Shenyang University), Ministry of Education, Shenyang, 110044, China.
| | - Ting Sun
- College of Sciences, Northeastern University, Shenyang, 110004, China.
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Gonzalez-Raymat H, Anagnostopoulos V, Denham M, Cai Y, Katsenovich YP. Unrefined humic substances as a potential low-cost amendment for the management of acidic groundwater contamination. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 212:210-218. [PMID: 29433000 DOI: 10.1016/j.jenvman.2018.02.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 02/01/2018] [Accepted: 02/03/2018] [Indexed: 06/08/2023]
Abstract
The present study explores a novel application of Huma-K, a commercially available, unrefined humic substance, as a promising low-cost source of organic matter for in situ remediation of contaminated acidic groundwater plumes. This can be achieved by creating a humic-rich coating on the surface of minerals which can enhance the sorption of contaminants from groundwater. Huma-K was characterized by means of scanning electron microscopy equipped with energy dispersive spectroscopy, Fourier-transform infrared analysis, and potentiometric titrations. Batch experiments were performed to investigate the sorption-desorption behavior of Huma-K and to evaluate what conditions (pH, contact time, and initial Huma-K concentration) affect these processes upon injection into aquifer sediments. As evidenced by potentiometric titrations, Huma-K possesses functional groups that have an acidic nature, with pK values in the range of 4-6 (carboxylic) and 9-10 (phenolic). Sorption, homogeneous precipitation, and surface-induced precipitation seem to be favored in the presence of sediment at pH 4, where there is less deprotonation of acidic functional groups. As the pH is increased, functional groups become negatively charged, leading to electrostatic repulsion and dissolution of Huma-K from sediment. Kinetic experiments indicate that Huma-K sorption is a slow-rate process, most likely governed by film diffusion. The enhanced sorption of Huma-K in acidic conditions suggests that it may be used to create a subsurface treatment zone in acidic aquifers for the sequestration of contaminants such as uranium. The treatment zone will persist as long as the pH does not increase sufficiently to cause soil-bound Huma-K to be released, remobilizing aqueous contaminants.
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Affiliation(s)
- Hansell Gonzalez-Raymat
- Department of Chemistry & Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL 33199, USA; Applied Research Center, Florida International University, 10555 W Flagler St., EC 2100, Miami, FL 33174, USA
| | - Vasileios Anagnostopoulos
- Applied Research Center, Florida International University, 10555 W Flagler St., EC 2100, Miami, FL 33174, USA
| | - Miles Denham
- Savannah River National Laboratory, Savannah River Site, Aiken, SC 29808, USA
| | - Yong Cai
- Department of Chemistry & Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL 33199, USA; Southeast Environmental Research Center, Florida International University, 11200 SW 8th St., Miami, FL 33199, USA
| | - Yelena P Katsenovich
- Applied Research Center, Florida International University, 10555 W Flagler St., EC 2100, Miami, FL 33174, USA.
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Gusiatin ZM, Kulikowska D, Klik B. Suitability of humic substances recovered from sewage sludge to remedy soils from a former As mining area - a novel approach. JOURNAL OF HAZARDOUS MATERIALS 2017; 338:160-166. [PMID: 28570874 DOI: 10.1016/j.jhazmat.2017.05.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/01/2017] [Accepted: 05/11/2017] [Indexed: 06/07/2023]
Abstract
Batch washing experiments were performed to evaluate the feasibility of using a solution of humic substances (HS) extracted from municipal sewage sludge as a washing agent to remove As from soils at a former As mining area. Soils (S1, S2, S3) differed in organic matter content, pH and As concentration. At pH 4 and a HS concentration of 4000mgTOCL-1, As removal efficiency ranged from 18% (S2) to 27% (S3). In all cases, As removal proceeded according to pseudo-second-order kinetics (equilibrium As concentrations ranged from 625mgkg-1 (S3) to 1250mgkg-1 (S3); rate constants, from 1.02×10-5kgmg-1min-1 (S1) to 2.05×10-5kgmg-1min-1 (S3). The time needed to reach equilibrium was 12h. With double washing, the efficiency of As removal was 1.5-times higher (on average) than with single washing. Double washing increased As stability, as indicated by the reduced partition index, especially in soils S1 and S3. Moreover, HS effectively decreased the content of the most toxic As(III) (by 95-97%).
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Affiliation(s)
- Zygmunt M Gusiatin
- Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Dorota Kulikowska
- Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland.
| | - Barbara Klik
- Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
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Li P, Ma X, Li H, Li S, Wu H, Xu D, Zheng G, Fan Q. Sorption mechanism of Th(IV) at iron oxyhydroxide (IOHO)/water interface: Batch, model and spectroscopic studies. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.06.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Duan G, Zhong Q, Bi L, Yang L, Liu T, Shi X, Wu W. The Poly(acrylonitrule-co-acrylic acid)-graft-β-cyclodextrin Hydrogel for Thorium(IV) Adsorption. Polymers (Basel) 2017; 9:polym9060201. [PMID: 30970880 PMCID: PMC6432136 DOI: 10.3390/polym9060201] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 05/22/2017] [Accepted: 05/25/2017] [Indexed: 11/20/2022] Open
Abstract
In this report, the β-CD(AN-co-AA) hydrogel was used to remove the thorium(IV) [Th(IV)] from the water system, and the new adsorbent was characterized through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The influences of contact time, pH value, ionic strength, solid-liquid ratio, initial Th(IV) concentration, and temperature on Th(IV) adsorption onto the functional hydrogel were researched. The results showed that the experimental data followed the Langmuir isotherm and the maximum adsorption capacity (qmax) for Th(IV) was 692 mg/g at pH 2.95, which approached the calculated (qe) 682 mg/g. The desorption capacity of Th(IV) in different HNO3 concentrations ranging from 0.005 to 0.5 M was also studied, and the percentage of the maximum desorption was 86.85% in the condition of 0.09 M HNO3. The selectivity of β-CD(AN-co-AA) hydrogel was also be studied, the results indicated that this material retained the good adsorption capacity to Th(IV) even when the Ca2+, Mg2+, or Pb2+ existed in the system. The findings indicate that β-CD(AN-co-AA) can be used as a new candidate for the enrichment and separation of Th(IV), or its analogue actinides, from large-volume solution in practical application.
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Affiliation(s)
- Guojian Duan
- College of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, China.
| | - Qiangqiang Zhong
- Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Lei Bi
- Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Liu Yang
- Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Tonghuan Liu
- Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
| | - Xiaoning Shi
- College of Pharmacy, Gansu University of Chinese Medicine, Lanzhou 730000, China.
| | - Wangsuo Wu
- Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China.
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Chen L, Yu X, Zhao Z, Dong Y. The Sorption of Th(IV) Ions onto Montmorillonite: The Effect of pH, Ionic Strength and Fulvic Acid. ADSORPT SCI TECHNOL 2016. [DOI: 10.1260/026361706779319616] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Lei Chen
- School of Chemical Engineering, Shandong University of Technology, 255049, Zibo, Shandong, P. R. China
| | - Xianjin Yu
- School of Chemical Engineering, Shandong University of Technology, 255049, Zibo, Shandong, P. R. China
| | - Zengdian Zhao
- School of Chemical Engineering, Shandong University of Technology, 255049, Zibo, Shandong, P. R. China
| | - Yunhui Dong
- School of Chemical Engineering, Shandong University of Technology, 255049, Zibo, Shandong, P. R. China
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Wu W, Fan Q, Lu S, Niu S, Wang X. Effect of Humic Acid on the Sorption and Kinetic Desorption of Radiocaesium Ions on/from Na-Rectorite Studied by the Batch Technique and a Chelating Resin. ADSORPT SCI TECHNOL 2016. [DOI: 10.1260/026361706780810294] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- W.S. Wu
- Radiochemistry Laboratory, Lanzhou University, Lanzhou, 730000, P. R. China
| | - Q.H. Fan
- Radiochemistry Laboratory, Lanzhou University, Lanzhou, 730000, P. R. China
- Institute of Plasma Physics, Chinese Academy of Sciences, P. O. Box 1126, 230031, Hefei, P. R. China
| | - S. Lu
- Institute of Plasma Physics, Chinese Academy of Sciences, P. O. Box 1126, 230031, Hefei, P. R. China
- New Star Institute of Applied Technology, Huangshan Road, Hefei, Anhui, P. R. China
| | - S. Niu
- Hebei Normal University of Science and Technology, Qinhuangdao, Hebei, P. R. China
| | - X. Wang
- Institute of Plasma Physics, Chinese Academy of Sciences, P. O. Box 1126, 230031, Hefei, P. R. China
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Abstract
Abstract
Natural sepiolite has been tested as a potential sorbent for the removal of Th(IV) from aqueous solutions by batch technique. Effects of various parameters on the adsorption process have been investigated. Under optimum conditions, Th(IV) was adsorbed with high adsorption efficiency. The results indicated that sorption of Th(IV) on sepiolite was strongly affected by pH values and temperature. The adsorption patterns of thorium on the sepiolite adsorbent followed the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The thermodynamic data (ΔH°, ΔS°, ΔG°) are calculated from the temperature-dependent sorption isotherms. The results suggest that sorption process of Th(IV) on sepiolite is spontaneous and endothermic.
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Affiliation(s)
- Kadriye Esen Erden
- Pamukkale University, Denizli Vocational School of Technical Sciences, Department of Electricity and Energy, 20160 Denizli, Turkey
| | - Ramazan Donat
- Pamukkale University, Faculty of Science and Arts, Department of Chemistry, 20070 Denizli, Turkey
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Wei W, Tian Z, Jiang L, Wang G, Cui J, Li S, Zhang Y, Wei Z. Adsorption behavior and mechanism of Cu(II) onto carbonate-substituted hydroxyapatite in the presence of humic acid. J DISPER SCI TECHNOL 2016. [DOI: 10.1080/01932691.2016.1218342] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Wei Wei
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, China
| | - Zhuangzhuang Tian
- School of Electronics and Information Engineering, Sias International University, Xinzheng, China
| | - Ling Jiang
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
| | - Gang Wang
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
| | - Jing Cui
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
| | - Shiyin Li
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
| | - Yong Zhang
- Department of Geographical Sciences, University of Alabama, Tuscaloosa, AL, USA
| | - Zhenggui Wei
- Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, School of Environment, Nanjing Normal University, Nanjing, China
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Li S, Wang X, Huang Z, Du L, Zhang D, Tan Z, Fu Y, Wang X. Sorption–desorption hysteresis of uranium(VI) on/from GMZ bentonite. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4831-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Li P, Liu Z, Ma F, Shi Q, Guo Z, Wu W. Effects of pH, ionic strength and humic acid on the sorption of neptunium(V) to Na-bentonite. J Mol Liq 2015. [DOI: 10.1016/j.molliq.2015.02.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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Chen X, Peng S, Wang J. Retention profile and kinetics characteristics of the radionuclide 90-Sr(II) onto kaolinite. J Radioanal Nucl Chem 2014. [DOI: 10.1007/s10967-014-3458-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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U(VI) sorption on illite: effect of pH, ionic strength, humic acid and temperature. J Radioanal Nucl Chem 2014. [DOI: 10.1007/s10967-014-3385-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Shcherbina NS, Kalmykov SS, Karpiouk LA, Ponomarenko SA, Hatfield K, Haire R, Perminova IV. Nonreversible immobilization of water-borne plutonium onto self-assembled adlayers of silanized humic materials. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:2226-2233. [PMID: 24533599 DOI: 10.1021/es404583f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The objective was to study plutonium partitioning between immobile and mobile humic materials at the water-solid interfaces. Immobilization of the humic materials on solid supports was performed in situ using self-adhesive silanized humic derivatives. The presence of the humic adlayers on solid supports was shown to significantly enhance Pu sorption and its retention under both steady state and dynamic conditions. While plutonium may exist in multiple oxidations states plus colloidal forms, the major thrust in this work was to study the behavior of most mobile--the PuO2(+) form in dilute solutions. The values of the plutonium partition coefficients (Kd) between water and humics-coated silica gels after 10 days exposure reached 1.6 × 10(4) L · kg(-1) at pH 7.5 under anaerobic conditions with a total plutonium concentration of 1.2 × 10(-8) M exceeding those for the uncoated SiO2 (6.3 × 10(2) L · kg(-1)). Column tests showed substantial sequestration of water-borne plutonium (up to 73%) on the humics-coated silica gels. Remobilization experiments conducted under batch conditions at different pH values (3.5, 4.5, 7.5) showed that no more than 3% of the sequestered Pu was remobilized from the humics-coated silica gels by treatment with dissolved humic materials at environmentally relevant pH of 7.5. Consequently, silanized humic materialas can be seen as both molecular probes and as potent candidate materials for scavenging mobile Pu from an aqueous phase.
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Affiliation(s)
- Natalia S Shcherbina
- Department of Chemistry, Lomonosov Moscow State University , Leninskie Gory 1-3, Moscow 119991, Russia
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Wang H, Zhang P, Ma X, Jiang S, Huang Y, Zhai L, Jiang S. Preparation, characterization of electrospun meso-hydroxylapatite nanofibers and their sorptions on Co(II). JOURNAL OF HAZARDOUS MATERIALS 2014; 265:158-165. [PMID: 24361493 DOI: 10.1016/j.jhazmat.2013.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/30/2013] [Accepted: 12/03/2013] [Indexed: 06/03/2023]
Abstract
In this work, mesoporous hydroxylapatite (meso-HA) nanofibers were prepared via calcination process with polyvinyl alcohol/HA (PVA/HA) hybrid nanofibers fabricated by electrospinning technique as precursors, and the removal efficiency of meso-HA nanofibers toward Co(II) was evaluated via sorption kinetics and sorption isotherms. Furthermore, the sorption behaviors of Co(II) on meso-HA nanofibers were explored as a function of pH, ionic strength, and thermodynamic parameters. There existed hydrogen bonds between HA and PVA matrix in precursor nanofibers which could change into meso-HA nanofibers with main pore diameter at 27nm and specific surface area at 114.26m(2)/g by calcination process. The sorption of Co(II) on meso-HA was strongly dependent on pH and ionic strength. Outer-sphere surface complexation or ion exchange was the main mechanisms of Co(II) adsorption on meso-HA at low pH, whereas inner-sphere surface complexation was the main adsorption mechanism at high pH. The sorption kinetic data were well fitted by the pseudo-second-order rate equation. The sorption isotherms could be well described by the Langmuir model. The thermodynamic parameters (ΔH°, ΔS° and ΔG°) calculated from the temperature-dependent sorption isotherms suggested that the sorption process of Co(II) on meso-HA nanofibers was spontaneous and endothermic.
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Affiliation(s)
- Hualin Wang
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
| | - Peng Zhang
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xingkong Ma
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Suwei Jiang
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Yan Huang
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Linfeng Zhai
- School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Shaotong Jiang
- School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
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19
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Role of solution chemistry on the trapping of radionuclide Th(IV) using titanate nanotubes as an efficient adsorbent. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-012-2389-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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20
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Removal of U(VI) from aqueous solutions by using attapulgite/iron oxide magnetic nanocomposites. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2360-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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99TcO4 − diffusion and sorption in compacted GMZ bentonite studied by capillary method. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2329-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Chi Y, Chen Y, Liu X, Guo Z, Xiao J, Xu J, Zhao W. Impact of environmental conditions on the sorption behavior of Pb(II) onto attapulgite. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2324-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Wang X. Interaction of radionickel with diatomite as a function of pH, ionic strength and temperature. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2295-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Chen JH, Lu DQ, Chen B, OuYang PK. Removal of U(VI) from aqueous solutions by using MWCNTs and chitosan modified MWCNTs. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2276-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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25
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Sorption of 63Ni(II) to montmorillonite as a function of pH, ionic strength, foreign ions and humic substances. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2253-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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Interaction of U(VI) with Na-attapulgite in the presence and absence of humic acid as a function of pH, ionic strength and temperature. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2265-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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27
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Sorption of Th(IV) from aqueous solution to GMZ bentonite: effect of pH, ionic strength, fulvic acid and electrolyte ions. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-1991-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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28
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Impact of environmental conditions on the sorption behavior of 60Co(II) on illite. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-1934-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Kandil AEHT, Saad EA, Aziz AAA, Aboelhasan AE. Study on adsorption behavior and separation efficiency of naturally occurring clay for some elements by batch experiments. ACTA ACUST UNITED AC 2012. [DOI: 10.5155/eurjchem.3.1.99-105.568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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30
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Impact of environmental conditions on the sorption behavior of UO2 2+ onto attapulgite studied by batch experiments. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-1666-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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31
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Perminova IV, Karpiouk LA, Ponomarenko SA, Hatfield K, Konstantinov AI, Hertkorn N, Muzafarov AM. Controlling aqueous sorption of humic substances on silica gel by directed alkoxysilyl-derivatization of their functionalities. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2011.12.068] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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32
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Impact of environmental conditions on the adsorption behavior of radionuclide 63Ni(II) on γ-Al2O3. Colloids Surf A Physicochem Eng Asp 2011. [DOI: 10.1016/j.colsurfa.2010.11.077] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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33
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Dong Y, Liu Z, Li Y. Effect of pH, ionic strength, foreign ions and humic substances on Th(IV) sorption to GMZ bentonite studied by batch experiments. J Radioanal Nucl Chem 2011. [DOI: 10.1007/s10967-011-1072-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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34
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Kar AS, Kumar S, Tomar BS, Manchanda VK. Sorption of curium by silica colloids: effect of humic acid. JOURNAL OF HAZARDOUS MATERIALS 2011; 186:1961-1965. [PMID: 21236572 DOI: 10.1016/j.jhazmat.2010.12.092] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 12/20/2010] [Accepted: 12/20/2010] [Indexed: 05/30/2023]
Abstract
Sorption of curium by silica colloids has been studied as a function of pH and ionic strength using (244)Cm as a tracer. The sorption was found to increase with increasing pH and reach a saturation value of ∼95% at pH beyond 5.3. The effect of humic acid on the sorption of (244)Cm onto silica was studied by changing the order of addition of the metal ion and humic acid. In general, in the presence of humic acid (2 mg/L), the sorption increased at lower pH (<5) while it decreased in the pH range 6.5-8 and above pH 8, the sorption was found to increase again. As curium forms strong complex with humic acid, its presence results in the enhancement of curium sorption at lower pH. At higher pH the humic acid present in the solution competes with the surface sites for curium thus decreasing the sorption. The decrease in the Cm sorption in presence of humic acid was found to be less when humic acid was added after the addition of curium. Linear additive model qualitatively reproduced the profile of the Cm(III) sorption by silica in presence of humic acid at least in the lower pH region, however it failed to yield quantitative agreement with the experimental results. The results of the present study evidenced the incorporation of Cm into the silica matrix.
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35
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36
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Effect of pH, ionic strength and humic substances on the adsorption of Uranium (VI) onto Na-rectorite. J Radioanal Nucl Chem 2010. [DOI: 10.1007/s10967-010-0846-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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37
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38
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The sorption of Eu(III) on calcareous soil: effects of pH, ionic strength, temperature, foreign ions and humic acid. J Radioanal Nucl Chem 2010. [DOI: 10.1007/s10967-010-0809-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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39
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Hu J, Xie Z, He B, Sheng G, Chen C, Li J, Chen Y, Wang X. Sorption of Eu(III) on GMZ bentonite in the absence/presence of humic acid studied by batch and XAFS techniques. Sci China Chem 2010. [DOI: 10.1007/s11426-010-3064-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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40
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Abstract
Sorption of neptunium on hematite colloids has been studied at varying pH values (3–10) in absence and presence of humic acid using239Np as a tracer. The experiments were carried out under aerobic and anaerobic conditions. The results show negligible sorption of Np(V) on hematite colloids at lower pH<5, beyond which it was found to increase sharply reaching ∼90% at pH 10. Presence of humic acid (2mg/L) was found to decrease the sorption of Np(V) on hematite at higher pH values while at lower pH the effect was found to be negligible. The stability constant of Np(V)-humate complex (logβ) was determined to be 4.2±0.2 by solvent extraction method. Sorption of humic acid on hematite as a function of pH was also measured by UV-visible spectrophotometry. Under nitrogen atmosphere and in presence of sodium dithionite, Np(V) was reduced to Np(IV) as evident by the enhanced sorption at all pH values, which was further enhanced in presence of humic acid at lower pH. However at higher pH values, humic acid does not affect the sorption of neptunium under reducing conditions, which could be due to competing reduction process involving ferric ions obtained from dissolved hematite.
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41
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Guerra DL, Viana RR, Airoldi C. Adsorption of thorium cation on modified clays MTTZ derivative. JOURNAL OF HAZARDOUS MATERIALS 2009; 168:1504-1511. [PMID: 19372006 DOI: 10.1016/j.jhazmat.2009.03.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2008] [Revised: 03/08/2009] [Accepted: 03/10/2009] [Indexed: 05/27/2023]
Abstract
Diquite (D) and bentonite (B) mineral samples from the Amazon region, Brazil, were modified by MTTZ derivative (5-mercapto-1-methyltetrazole) using heterogeneous route. These materials were characterized by textural and elemental analysis, transmission electron microscopy (TEM), power X-ray diffraction and (13)C NMR spectroscopy. The chemically modified clay (D(MTTZ) and B(MTTZ)) samples showed modification of its physical-chemical properties including: specific area 41.4 (B) to 398.5m(2)g(-1) (B(MTTZ)) and 25.0 (D) to 178.8m(2)g(-1) (D(MTTZ)). The adsorption experiments performed under batch process with Th(IV) concentration, pH and contact time as variables. The ability of these materials to remove thorium from aqueous solution was followed by a series of adsorption isotherms adjusted to a Sips equation at room temperature and pH 2.0, with variable concentration of Th(IV). The maximum number of moles adsorbed was determined to be 10.45 x 10(-2) and 12.76 x 10(-2)mmol g(-1) for D(MTTZ) and B(MTTZ), respectively. The energetic effects (Delta(int)H degrees , Delta(int)G degrees and Delta(int)S degrees ) caused by thorium cation adsorption were determined through calorimetric titrations.
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Affiliation(s)
- Denis L Guerra
- Chemistry Institute, State University of Campinas, São Paulo, Brazil.
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42
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Effect of pH, ionic strength and humic acid on the sorption of uranium(VI) to attapulgite. Appl Radiat Isot 2009; 67:1582-90. [DOI: 10.1016/j.apradiso.2009.03.113] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 02/24/2009] [Accepted: 03/31/2009] [Indexed: 11/18/2022]
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43
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Ren X, Wang S, Yang S, Li J. Influence of contact time, pH, soil humic/fulvic acids, ionic strength and temperature on sorption of U(VI) onto MX-80 bentonite. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-0323-0] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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44
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Effect of pH, ionic strength and temperature on the sorption of radionickel on Na-montmorillonite. Appl Radiat Isot 2009; 67:1007-12. [DOI: 10.1016/j.apradiso.2009.02.085] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 02/16/2009] [Accepted: 02/19/2009] [Indexed: 11/22/2022]
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45
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Adsorption of Pb(II) on diatomite as affected via aqueous solution chemistry and temperature. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2009.02.016] [Citation(s) in RCA: 253] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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46
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Sheng GD, Shao DD, Fan QH, Xu D, Chen YX, Wang XK. Effect of pH and ionic strength on sorption of Eu(III) to MX-80 bentonite: batch and XAFS study. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2009.1656] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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47
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Effect of pH, ionic strength, fulvic acid and humic acid on sorption of Th(IV) on Na-rectorite. J Radioanal Nucl Chem 2008. [DOI: 10.1007/s10967-006-6865-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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48
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Sheng G, Hu J, Wang X. Sorption properties of Th(IV) on the raw diatomite—Effects of contact time, pH, ionic strength and temperature. Appl Radiat Isot 2008; 66:1313-20. [DOI: 10.1016/j.apradiso.2008.03.005] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 01/07/2008] [Accepted: 03/04/2008] [Indexed: 11/17/2022]
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49
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Chen L, Gao X. Thermodynamic study of Th(IV) sorption on attapulgite. Appl Radiat Isot 2008; 67:1-6. [PMID: 18951031 DOI: 10.1016/j.apradiso.2008.05.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 03/31/2008] [Accepted: 05/15/2008] [Indexed: 11/24/2022]
Abstract
Sorption of Th(IV) on attapulgite was studied as a function of pH and temperature under ambient conditions using batch technique. The results indicated that sorption of Th(IV) on attapulgite was strongly affected by pH values and temperature. The kinetic sorption of Th(IV) can be described by pseudo-second-order rate very well. Sorption isotherms of Th(IV) at 293.15, 308.15 and 323.15K were modeled by Langmuir and Dubinin-Radushkevich models very well, and the parameters indicated that the sorption of Th(IV) on attapulgite was strongly dependent on temperature and the sorption of Th(IV) increased with increasing temperature of the system. Enthalpy (DeltaH(0)), entropy (DeltaS(0)) and Gibbs free energy (DeltaG(0)) were calculated from the temperature dependent sorption data, and the results indicated that the sorption of Th(IV) on attapulgite was a spontaneous process, and the sorption was endothermic.
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Affiliation(s)
- Lei Chen
- School of Chemical Engineering, Shandong University of Technology, Zibo, 255049 Shandong, China
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50
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Sachs S, Bernhard G. Sorption of U(VI) onto an artificial humic substance-kaolinite-associate. CHEMOSPHERE 2008; 72:1441-1447. [PMID: 18597817 DOI: 10.1016/j.chemosphere.2008.05.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 05/08/2008] [Accepted: 05/15/2008] [Indexed: 05/26/2023]
Abstract
An artificial humic substance-kaolinite-associate (HSKA) was synthesized as a model substance for natural clays containing organic matter in clay formations, soils, and sediments. The U(VI) sorption onto this model substance was studied in batch experiments as a function of pH and compared to the U(VI) sorption onto kaolinite in absence and presence of separately added humic acid (HA). The HSKA has a TOC content of 4.9 mg g(-1). It was found that the humic matter associated with kaolinite exhibits an immobilizing as well as an mobilizing effect on U(VI). Between pH 3 and 5, humic matter causes an increase of the U(VI) sorption onto kaolinite, whereas at pH above 5 the release of humic matter from the associate into the solution and the formation of dissolved uranyl humate complexes reduces the U(VI) sorption. The U(VI) sorption onto the synthetic HSKA differs from that of U(VI) in the system U(VI)/HA/kaolinite with comparable amounts of separately added HA. Separately added HA causes a stronger mobilizing effect on U(VI) than humic matter present in HSKA. This can be attributed to structural and functional dissimilarities of the humic substances.
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Affiliation(s)
- S Sachs
- Forschungszentrum Dresden-Rossendorf, Institute of Radiochemistry, P.O. Box 510 119, 01314 Dresden, Germany.
| | - G Bernhard
- Forschungszentrum Dresden-Rossendorf, Institute of Radiochemistry, P.O. Box 510 119, 01314 Dresden, Germany
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