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Hamidi F, Baghani AN, Kasraee M, Salari M, Mehdinejad MH. Modeling, optimization and efficient use of MMT K 10 nanoclay for Pb (II) removal using RSM, ANN and GA. Sci Rep 2023; 13:8434. [PMID: 37225791 DOI: 10.1038/s41598-023-35709-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 05/22/2023] [Indexed: 05/26/2023] Open
Abstract
Regarding the long-term toxic effects of Pb (II) ions on human health and its bioaccumulation property, taking measures for its reduction in the environment is necessary. The MMT-K10 (montmorillonite-k10) nanoclay was characterized by XRD, XRF, BET, FESEM, and FTIR. The effects of pH, initial concentrations, reaction time, and adsorbent dosage were studied. The experimental design study was carried out with RSM-BBD method. Results prediction and optimization were investigated with RSM and artificial neural network (ANN)-genetic algorithm (GA) respectively. The RSM results showed that the experimental data followed the quadratic model with the highest regression coefficient value (R2 = 0.9903) and insignificant lack of fit (0.2426) showing the validity of the Quadratic model. The optimal adsorption conditions were obtained at pH 5.44, adsorbent = 0.98 g/l, concentration of Pb (II) ions = 25 mg/L, and reaction time = 68 min. Similar optimization results were observed by RSM and artificial neural network-genetic algorithm methods. The experimental data revealed that the process followed the Langmuir isotherm and the maximum adsorption capacity was 40.86 mg/g. Besides, the kinetic data indicated that the results fitted with the pseudo-second-order model. Hence, the MMT-K10 nanoclay can be a suitable adsorbent due to having a natural source, simple and inexpensive preparation, and high adsorption capacity.
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Affiliation(s)
- Farshad Hamidi
- Department of Environmental Health Engineering, School of Public Health, Environmental Health Research Center, Golestan University of Medical Sciences, Gorgan, Iran
| | - Abbas Norouzian Baghani
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mahboobeh Kasraee
- Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Salari
- Department of Environmental Health Engineering, School of Public Health, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Mohammad Hadi Mehdinejad
- Department of Environmental Health Engineering, School of Public Health, Environmental Health Research Center, Golestan University of Medical Sciences, Gorgan, Iran.
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2
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Sirajunnisa P, Sabna C, Aswin A, Prathapan S, Sailaja GS. Lawsone-bentonite hybrid systems for pH-dependent sustained release of ciprofloxacin. NEW J CHEM 2022. [DOI: 10.1039/d2nj00288d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Biocompatible lawsone-bentonite hybrid systems for pH-dependent sustained release of ciprofloxacin.
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Affiliation(s)
- P. Sirajunnisa
- Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kerala, 682022, India
| | - Cheemadan Sabna
- Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kerala, 682022, India
| | - A. Aswin
- Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kerala, 682022, India
| | - S. Prathapan
- Department of Applied Chemistry, Cochin University of Science and Technology, Kerala, 682022, India
| | - G. S. Sailaja
- Department of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kerala, 682022, India
- Centre for Excellence in Advanced Materials, Cochin University of Science and Technology, Kerala, 682022, India
- Inter University Centre for Nanomaterials and Devices (IUCND), Cochin University of Science and Technology, Kerala, 682022, India
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3
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Salmas CE, Giannakas AE, Baikousi M, Kollia E, Tsigkou V, Proestos C. Effect of Copper and Titanium-Exchanged Montmorillonite Nanostructures on the Packaging Performance of Chitosan/Poly-Vinyl-Alcohol-Based Active Packaging Nanocomposite Films. Foods 2021; 10:foods10123038. [PMID: 34945592 PMCID: PMC8700973 DOI: 10.3390/foods10123038] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 11/30/2021] [Accepted: 12/03/2021] [Indexed: 01/12/2023] Open
Abstract
In this study, CuMt and TiMt montmorillonites were produced via an ion-exchange process with Cu+ and Ti4+ ions. These nanostructured materials were characterized with X-ray diffraction (XRD) and fourier transform infrared spectroscopy (FTIR) measurements and added as nanoreinforcements and active agents in chitosan (CS)/poly-vinyl-alcohol (PVOH)-based packaging films. The developed films were characterized by XRD and FTIR measurements. The antimicrobial, tensile, and oxygen/water-barrier measurements for the evaluation of the packaging performance were carried out to the obtained CS/PVOH/CuMt and CS/PVOH/TiMt films. The results of this study indicated that CS/PVOH/CuMt film is a stronger intercalated nanocomposite structure compared to the CS/PVOH/TiMt film. This fact reflected higher tensile strength and water/oxygen-barrier properties. The antibacterial activity of these films was tested against four food pathogenic bacteria: Escherichia coli, Staphylococcus aureus, Salmonella enterica and Listeria monocytogenes. Results showed that in most cases, the antibacterial activity was generated by the CuMt and TiMt nanostructures. Thus, both CS/PVOH/CuMt and CS/PVOH/TiMt films are nanocomposite candidates with very good perspectives for future applications on food edible active packaging.
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Affiliation(s)
- Constantinos E. Salmas
- Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece;
- Correspondence: (C.E.S.); (C.P.)
| | - Aris E. Giannakas
- Department of Food Science and Technology, University of Patras, 30100 Agrinio, Greece;
| | - Maria Baikousi
- Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece;
| | - Eleni Kollia
- Laboratory of Food Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Zografou, 15771 Athens, Greece; (E.K.); (V.T.)
| | - Vasiliki Tsigkou
- Laboratory of Food Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Zografou, 15771 Athens, Greece; (E.K.); (V.T.)
| | - Charalampos Proestos
- Laboratory of Food Chemistry, Department of Chemistry, National and Kapodistrian University of Athens Zografou, 15771 Athens, Greece; (E.K.); (V.T.)
- Correspondence: (C.E.S.); (C.P.)
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4
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The Study of Reverse Water Gas Shift Reaction Activity over Different Interfaces: The Design of Cu-Plate ZnO Model Catalysts. Catalysts 2020. [DOI: 10.3390/catal10050533] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
CO2 hydrogenation to methanol is one of the main and valuable catalytic reactions applied on Cu/ZnO-based catalysts; the interface formed through Zn migration from ZnO support to the surface of Cu nanoparticle (ZnOx-Cu NP-ZnO) has been reported to account for methanol synthesis from CO2 hydrogenation. However, the accompanied reverse water gas shift (RWGS) reaction significantly decreases methanol selectivity and deactivates catalysts soon. Inhibition of RWGS is thus of great importance to afford high yield of methanol. The clear understanding of the reactivity of RWGS reaction on both the direct contact Cu-ZnO interface and ZnOx-Cu NP-ZnO interface is essential to reveal the low methanol selectivity in CO2 hydrogenation to methanol and look for efficient catalysts for RWGS reaction. Cu doped plate ZnO (ZnO:XCu) model catalysts were prepared through a hydrothermal method to simulate direct contact Cu-ZnO interface and plate ZnO supported 1 wt % Cu (1Cu/ZnO) catalyst was prepared by wet impregnation for comparison in RWGS reaction. Electron paramagnetic resonance (EPR), XRD, SEM, Raman, hydrogen temperature-programmed reduction (H2-TPR) and CO2 temperature-programmed desorption (CO2-TPD) were employed to characterize these catalysts. The characterization results confirmed that Cu incorporated into ZnO lattice and finally formed direct contact Cu-ZnO interface after H2 reduction. The catalytic performance revealed that direct contact Cu-ZnO interface displays inferior RWGS reaction reactivity at reaction temperature lower than 500 °C, compared with the ZnOx-Cu NP-ZnO interface; however, it is more stable at reaction temperature higher than 500 °C, enables ZnO:XCu model catalysts superior catalytic activity to that of 1Cu/ZnO. This finding will facilitate the designing of robust and efficient catalysts for both CO2 hydrogenation to methanol and RWGS reactions.
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Srasra E, Bekri-Abbes I. Bentonite Clays for Therapeutic Purposes and Biomaterial Design. Curr Pharm Des 2020; 26:642-649. [DOI: 10.2174/1381612826666200203144034] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/25/2019] [Indexed: 11/22/2022]
Abstract
Background:Bentonite is a natural clay composed mainly of montmorillonite with other associated minerals such as feldspar, calcite and quartz. Owing to its high cation exchange, large surface area and ability to form thixotropic gels with water and to absorb large quantities of gas, it presents a large medicinal application.Objective:This review focuses on the promising potential of bentonite clays for biomaterial design and for therapeutic purposes.Methods:PubMed, ACS publications and Elsevier were searched for relevant papers. We have also evaluated the references of some pertinent articles.Results:Healing properties of bentonite are derived from the crystalline structure of the smectite group, which is composed of two octahedral alumina sheets localized between two tetrahedral silica sheets. This structure is behind the ability to intercalate cationic bioactive agents and undergoes interaction with various toxic species and exchanging in return species such as Fe3+, Cu2+, Al3+ Ca2+ or Na+, presenting antibacterial activity and providing essential minerals to the body. Furthermore, due to to its layered structure, bentonite has wide application for the design of biomaterials providing, thus, the stability of bioactive agents and preventing them from aggregation.Conclusion:Numerous publications have cited bentonite extensive applications as an alternative and complementary treatment for numerous health conditions as a detoxifying agent and for the preparation of several bionanocomposites.
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Affiliation(s)
- Ezzeddine Srasra
- Laboratory of Composite Materials and Clay Minerals National Center of Material Sciences, Technopole of Borj Cedria, Soliman, Tunisia
| | - Imene Bekri-Abbes
- Laboratory of Composite Materials and Clay Minerals National Center of Material Sciences, Technopole of Borj Cedria, Soliman, Tunisia
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6
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Li Z, Chang PH, Jiang WT. Mechanisms of Cu 2+, triethylenetetramine (TETA), and Cu-TETA sorption on rectorite and its use for metal removal via metal-TETA complexation. JOURNAL OF HAZARDOUS MATERIALS 2019; 373:187-196. [PMID: 30921569 DOI: 10.1016/j.jhazmat.2019.03.085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 02/08/2019] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
Uptake of metals, organics, and formation of metal-organic complexes on the surface or in the interlayer of clay minerals had been studied extensively over the last half century. In this study, we investigated the uptake mechanisms of Cu2+, triethylenetetramine (TETA), and Cu-TETA on rectorite and its use for metal removal via metal-TETA complexation. The uptake of Cu2+, TETA, and Cu-TETA by rectorite occurred on the external as well as in the interlayer space, resulting in a change of d001-spacing due to differences in sizes of interlayer cations or complexes. Although the uptake of Cu2+ and Cu-TETA by rectorite was via a cation exchange process as evidenced by the stoichiometric desorption of dominant interlayer cation Ca2+, the uptake of TETA alone on rectorite was via complexation with interlayer cation Ca2+. Due to strong affinity of TETA for Cu2+, significant amounts of Cu2+ uptake occurred on TETA-rectorite. Desorption of Ca2+ from TETA-rectorite confirmed the replacement of interlayer cation Ca2+ by Cu2+. However, the replacement of Ca2+ by Cu2+ in TETA-rectorite did not involved in removal of TETA. As such, TETA-modified clay minerals may serve as a type of sorbents for the removal of selected heavy metals via surface or interlayer via complexation.
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Affiliation(s)
- Zhaohui Li
- Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, 29 Xueyuan Road, Beijing 100083, China; Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan; Department of Geosciences, University of Wisconsin - Parkside, 900 Wood Road, Kenosha, WI 53144, USA.
| | - Po-Hsiang Chang
- Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan
| | - Wei-Teh Jiang
- Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan.
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7
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Gamba M, Lázaro-Martínez JM, Olivelli MS, Yarza F, Vega D, Curutchet G, Torres Sánchez RM. Kinetic and equilibrium adsorption of two post-harvest fungicides onto copper-exchanged montmorillonite: synergic and antagonistic effects of both fungicides' presence. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:2421-2434. [PMID: 30467755 DOI: 10.1007/s11356-018-3638-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 10/30/2018] [Indexed: 06/09/2023]
Abstract
The simultaneous adsorption of both imazalil (IMZ) and thiabendazole (TBZ) fungicides in a Cu2+-exchanged Mt was studied in this work. Kinetic studies were used to determine the rate law which describes the adsorption of individual fungicides onto the adsorbent. Adsorption isotherm of individual and combined fungicides was done to evaluate synergic or antagonistic effects. The Mt-Cu material considerably improved TBZ and/or IMZ adsorption from aqueous suspensions with respect to raw Mt, leading to removal efficiencies higher than 99% after 10 min of contact time for TBZ and IMZ Ci = 15 and 40 mg/L, respectively, when a solid dosage = 1 g/L was used. The adsorption sites involved were determined by a combination of X-ray diffraction (XRD) determinations and electron paramagnetic resonance (EPR), indicating that fungicides were bonded to Cu2+ cations, while the rate limiting step was the formation of coordination bonds. The adsorption mechanism proposed is that of ligand exchange between water and fungicide molecules in the metal coordination sphere. The single-crystal structure for the IMZ-Cu2+ complex indicated that four molecules were bounded to the copper centers, while two molecules of TBZ are bounded to copper explaining the higher IMZ uptake capacity for the Mt-Cu material. Graphical abstract.
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Affiliation(s)
- Martina Gamba
- CETMIC-CONICET-CCT La Plata-CIC, Camino Centenario y 506, (1897) M. B. Gonnet, La Plata, Argentina
| | - Juan M Lázaro-Martínez
- IQUIMEFA -CONICET, Facultad de Farmacia y Bioquímica, Departamento de Química Orgánica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Melisa S Olivelli
- Escuela de Ciencia y Tecnología e Instituto de Investigación e Ingeniería Ambiental, CONICET, Universidad Nacional de San Martín, Av. 25 de Mayo y Francia, 1650 General San Martín, Buenos Aires, Argentina
| | - Florencia Yarza
- CETMIC-CONICET-CCT La Plata-CIC, Camino Centenario y 506, (1897) M. B. Gonnet, La Plata, Argentina
| | - Daniel Vega
- Departamento de Física de la Materia Condensada, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499 (1650) San Martín, Buenos Aires, Argentina
| | - Gustavo Curutchet
- Escuela de Ciencia y Tecnología e Instituto de Investigación e Ingeniería Ambiental, CONICET, Universidad Nacional de San Martín, Av. 25 de Mayo y Francia, 1650 General San Martín, Buenos Aires, Argentina
| | - Rosa M Torres Sánchez
- CETMIC-CONICET-CCT La Plata-CIC, Camino Centenario y 506, (1897) M. B. Gonnet, La Plata, Argentina.
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8
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Khodaeimehr R, Peighambardoust SJ, Peighambardoust SH. Preparation and Characterization of Corn Starch/Clay Nanocomposite Films: Effect of Clay Content and Surface Modification. STARCH-STARKE 2018. [DOI: 10.1002/star.201700251] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rouhollah Khodaeimehr
- Faculty of Chemical and Petroleum Engineering; University of Tabriz; Tabriz 5166616471 Iran
| | - Seyed Jamaleddin Peighambardoust
- Associate Professor of Polymer Science and Technology; Faculty of Chemical and Petroleum Engineering; University of Tabriz; Tabriz 5166616471 Iran
| | - Seyed Hadi Peighambardoust
- Professor of Food Technology Department of Food Science; College of Agriculture; University of Tabriz; Tabriz 5166616471 Iran
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9
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Martucci JF, Ruseckaite RA. Antibacterial activity of gelatin/copper (II)-exchanged montmorillonite films. Food Hydrocoll 2017. [DOI: 10.1016/j.foodhyd.2016.10.030] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Nurtay M, Tuersun M, Cai Y, Açıkgöz M, Wang H, Pan Y, Zhang X, Ma X. Spectroscopic study for a chromium-adsorbed montmorillonite. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 173:114-121. [PMID: 27619973 DOI: 10.1016/j.saa.2016.08.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 06/06/2023]
Abstract
Samples of purified montmorillonite with trace amounts of quartz were subjected to different concentrations of chromium sulphate solutions for one week to allow cation exchange. The chromium-bearing montmorillonites were verified and tested using powder X-ray diffractometry (XRD), X-ray fluorescence spectrometry, electron spin resonance (ESR) spectrometry and Fourier transformation infrared (FTIR) spectroscopy to explore the occupation sites of the chromium. The ESR spectra recorded before and after the chromium exchange show clear differences: a strong and broad resonance with two shoulders at the lower magnetic field side was present to start, and its intensity as well as that of the ferric iron resonance, increased with the concentration of added chromium. The signals introduced by the chromium, for example at g=1.975 and 2.510 etc., suggested that the chromium had several occupational sites. The ESR peak with g=2.510 in the second derivative spectrum suggested that Cr3+ was weakly bounded to TOT with the form of [Cr(H2O)3]3+ in hexagonal cavities. This was verified by comparing the FTIR spectra of the pure and modified montmorillonite. The main resonance centred at g=1.975 indicated that the majority of Cr3+ occupied the interlayer region as [Cr(H2O)6]3+. The substitution of Ca2+ by Cr3+ also greatly affected the vibration of the hydrogens associate to water, ranged from 3500 to 2600cm-1 in FTIR. Furthermore, the presence of two diffraction lines in the XRD results (specifically those with d-values of 1.5171 and 1.2673nm) and the calculations of the size of the interlayer space suggested the presence of two types of montmorillonite with different hydration cations in the sample exposed to 0.2M chromium sulphate. The two diffraction lines were assigned to [Cr(H2O)6]3+ and [Cr(H2O)3O3]3+, respectively. This also suggested that the species of hydration cation was constrained by the concentration of the chromium solution.
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Affiliation(s)
- Maidina Nurtay
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China
| | - Maierdan Tuersun
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China
| | - Yuanfeng Cai
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China.
| | - Muhammed Açıkgöz
- Faculty of Engineering and Natural Sciences, Bahcesehir University, Beşiktaş, 34353 Istanbul, Turkey
| | - Hongtao Wang
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China.
| | - Yuguan Pan
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China
| | - Xiaoke Zhang
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China
| | - Xiaomei Ma
- State Key Laboratory of Metal Ore Deposits, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210046, China
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11
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Natkański P, Rokicińska A, Wach A, Drozdek M, Dudek B, Lityńska-Dobrzyńska L, Kuśtrowski P. Physicochemical properties of hydrogel template-synthesized copper(ii) oxide-modified clay influencing its catalytic activity in toluene combustion. RSC Adv 2016. [DOI: 10.1039/c6ra16278a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
CuO-modified montmorillonite was synthesized by the template-assisted route.
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Affiliation(s)
- Piotr Natkański
- Faculty of Chemistry
- Jagiellonian University
- 30-060 Kraków
- Poland
| | - Anna Rokicińska
- Faculty of Chemistry
- Jagiellonian University
- 30-060 Kraków
- Poland
| | - Anna Wach
- Faculty of Chemistry
- Jagiellonian University
- 30-060 Kraków
- Poland
| | - Marek Drozdek
- Faculty of Chemistry
- Jagiellonian University
- 30-060 Kraków
- Poland
| | - Barbara Dudek
- Faculty of Chemistry
- Jagiellonian University
- 30-060 Kraków
- Poland
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12
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Li B, Li LY, Grace JR. Adsorption and hydraulic conductivity of landfill-leachate perfluorinated compounds in bentonite barrier mixtures. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 156:236-243. [PMID: 25867101 DOI: 10.1016/j.jenvman.2015.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 03/31/2015] [Accepted: 04/01/2015] [Indexed: 06/04/2023]
Abstract
Perfluorinated compounds (PFCs) are leached in landfills from a wide range of domestic and industrial products. Sodium bentonite, a common barrier material, was contacted with water and landfill leachate spiked with PFCs in batch adsorption tests to measure PFC adsorption. Leaching cell tests were also conducted in which water, landfill leachate and PFC-spiked leachate permeated through compacted sand-bentonite mixtures. It was found that the PFCs did not bind substantially to the bentonite. Hydraulic conductivities were not appreciably affected by the PFCs, showing that bentonite liners are not affected for the range of concentrations tested. The sand-bentonite mixture partially retained the PFCs, indicating limited effectiveness in containing PFC within landfills.
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Affiliation(s)
- Belinda Li
- Department of Civil Engineering, University of British Columbia, 6250 Applied Science Lane, Vancouver, BC V6T 1Z4, Canada
| | - Loretta Y Li
- Department of Civil Engineering, University of British Columbia, 6250 Applied Science Lane, Vancouver, BC V6T 1Z4, Canada.
| | - John R Grace
- Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada
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Zhu R, Chen Q, Wang X, Wang S, Zhu J, He H. Templated synthesis of nitrogen-doped graphene-like carbon materials using spent montmorillonite. RSC Adv 2015. [DOI: 10.1039/c4ra13732a] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This work provided a method that can recycle the spent montmorillonite and synthesize heteroatom-doped graphene-like materials.
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Affiliation(s)
- Runliang Zhu
- CAS Key Laboratory of Mineralogy and Metallogeny
- Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development
- Guangzhou Institute of Geochemistry
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Qingze Chen
- CAS Key Laboratory of Mineralogy and Metallogeny
- Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development
- Guangzhou Institute of Geochemistry
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Xin Wang
- State Key Laboratory of Chem/Bio-Sensing and Chemometrics
- College of Chemistry & Chemical Engineering
- Hunan University
- Changsha 410082
- China
| | - Shuangyin Wang
- State Key Laboratory of Chem/Bio-Sensing and Chemometrics
- College of Chemistry & Chemical Engineering
- Hunan University
- Changsha 410082
- China
| | - Jianxi Zhu
- CAS Key Laboratory of Mineralogy and Metallogeny
- Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development
- Guangzhou Institute of Geochemistry
- Chinese Academy of Sciences
- Guangzhou 510640
| | - Hongping He
- CAS Key Laboratory of Mineralogy and Metallogeny
- Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development
- Guangzhou Institute of Geochemistry
- Chinese Academy of Sciences
- Guangzhou 510640
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14
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Ren W, Teng Y, Zhou Q, Paschke A, Schüürmann G. Sorption of chlorimuron-ethyl on montmorillonite clays: effects of exchangeable cations, pH, and ionic strength. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:11587-11597. [PMID: 25028319 DOI: 10.1007/s11356-014-3139-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 06/02/2014] [Indexed: 06/03/2023]
Abstract
Sorption interaction of chlorimuron-ethyl with montmorillonite clays was investigated under varied types of exchangeable cation, pH, and ionic strength conditions. Chlorimuron-ethyl sorption on bentonites exhibited pronounced cation dependency, and the sorption ability increased as the sequence Ca(2+)- < Na(+)- < Al(3+)- < Fe(3+)-bentonite, due to different sorption mechanisms, whereas the cation dependency was influenced by the clay type and much weaker for montmorillonites. The decrease of pH at the range of 4.0-6.0 prominently increased sorption of chlorimuron-ethyl on all cation-exchanged montmorillonite clays, and nearly a neglected sorption (about 2 %) can be observed at pH over 7.0. In the presence of CaCl2, sorption of chlorimuron-ethyl on Fe(3+)-bentonite was promoted because of complexion of Ca(2+) and the surface of Fe(3+)-bentonite. However, as the concentration of CaCl2 increased, chlorimuron-ethyl sorption on Ca(2+)- and Fe(3+)-exchanged bentonite decreased, suggesting that Ca bridging was not the prevailing mechanism for sorption of chlorimuron-ethyl on these clays. Furthermore, chlorimuron-ethyl sorption was relatively sensitive to pH, and the change of pH may obscure effect of other factors on the sorption, so it was quite necessary to control pH at a constant value when the effect of other factor was being studied.
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Affiliation(s)
- Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
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Brtáňová A, Madejová J, Bizovská V, Komadel P. Utilization of near infrared spectroscopy for studying solvation properties of Cu-montmorillonites. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 123:385-391. [PMID: 24412792 DOI: 10.1016/j.saa.2013.12.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 11/21/2013] [Accepted: 12/03/2013] [Indexed: 06/03/2023]
Abstract
The benefit of near infrared (NIR) spectroscopy to follow the adsorption of dimethylsulfoxide and acetonitrile on reduced-charge Cu-montmorillonites differing in their chemical composition is presented. A NIR UpDRIFT accessory enabling measurement of spectra directly in closed glass vials was used to determine the amounts of adsorbed solvents. The area of the complex 2νCH band correlated very well with gravimetric analysis confirming that the UpDRIFT technique is suitable for studies of total content of organic solvents adsorbed on montmorillonites. Changes of the 2νOH band revealed that acetonitrile with a lower dipole moment (DP) and Gutmann donor number (GDN) fully solvated all samples heated up to 200°C and only partially those heated at 300°C, while DMSO with a higher DP and GDN completely solvated all the samples. These results indicate that fixation of Cu(2+) cations in montmorillonites upon heating is a partially reversible process.
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Affiliation(s)
- Anna Brtáňová
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia.
| | - Jana Madejová
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia.
| | - Valéria Bizovská
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia.
| | - Peter Komadel
- Institute of Inorganic Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, 845 36 Bratislava, Slovakia.
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16
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Kar P, Samantaray S, Mishra BG. Catalytic application of chromia-pillared montmorillonite towards environmentally benign synthesis of octahydroxanthenes. REACTION KINETICS MECHANISMS AND CATALYSIS 2012. [DOI: 10.1007/s11144-012-0499-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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17
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Zhou Q, Deng S, Yu Q, Zhang Q, Yu G, Huang J, He H. Sorption of perfluorooctane sulfonate on organo-montmorillonites. CHEMOSPHERE 2010; 78:688-694. [PMID: 20042218 DOI: 10.1016/j.chemosphere.2009.12.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 11/27/2009] [Accepted: 12/07/2009] [Indexed: 05/28/2023]
Abstract
Perfluorinated compound as one of the emerging pollutants has caused great attention in recent years. In this study, the organo-montmorillonites (organo-Mts) with different amounts and arrangements of hexadecyltrimethylammonium bromide (HDTMAB) were prepared as effective sorbents for PFOS removal from water. Batch sorption experiments including sorption kinetics, sorption isotherm as well as effect of solution pH were studied. The Elovich and pseudo-second-order models were selected to fit the kinetic data and the latter described the sorption kinetic better. Sorption isotherms showed that the sorption amount of PFOS increased with increasing amount of HDTMAB loaded in the montmorillonites, indicating that hydrophobic interaction played an important role in the sorption process. Comparative sorption of other perfluorinated compounds (PFCs) with different length of C-F chains and different functional groups further verified that hydrophobic interaction was the main force for the sorption of PFCs on the organo-Mts. X-ray diffraction (XRD) analysis demonstrated the significant decrease of interlayer distance after PFOS sorption, suggesting that the HDTMAB molecules were rearranged in the interlayer of organo-Mts. The PFOS molecules first diffused into the organo-Mts via hydrophobic interaction, and then the rearrangement occurred through electrostatic interaction between the two surfactants, resulting in the microstructure change within the organo-Mts.
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Affiliation(s)
- Qin Zhou
- POPs Research Center, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, PR China
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18
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Synthesis, characterization of mono, di and tri alkyl surfactant intercalated Wyoming montmorillonite for the removal of phenol from aqueous systems. J Colloid Interface Sci 2008; 327:287-94. [DOI: 10.1016/j.jcis.2008.08.049] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Revised: 08/26/2008] [Accepted: 08/27/2008] [Indexed: 11/20/2022]
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19
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Daković A, Matijasević S, Rottinghaus GE, Ledoux DR, Butkeraitis P, Sekulić Z. Aflatoxin B(1) adsorption by natural and copper modified montmorillonite. Colloids Surf B Biointerfaces 2008; 66:20-5. [PMID: 18585010 DOI: 10.1016/j.colsurfb.2008.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Revised: 05/08/2008] [Accepted: 05/08/2008] [Indexed: 10/22/2022]
Abstract
Adsorption of aflatoxin B(1) (AFB1) by natural montmorillonite (MONT) and montmorillonite modified with copper ions (Cu-MONT) was investigated. Both MONTs were characterized using the X-ray powder diffraction (XRPD) analysis, thermal analysis (DTA/TGA) and scanning electron miscroscopy/electron dispersive spectroscopy (SEM/EDS). The results of XRPD and SEM/EDS analyses of Cu-MONT suggested partial ion exchange of native inorganic cations in MONT with copper occurred. Investigation of AFB1 adsorption by MONT and Cu-MONT, at pH 3, 7 or 9, showed that adsorption of this toxin by both MONTs was high (over 93%). Since AFB1 is nonionizable, no differences in AFB1 adsorption by both MONTs, at different pHs, were observed, as expected. Futhermore, it was determined that adsorption of AFB1 by both MONTs followed a non-linear (Langmuir) type of isotherm, at pH 3. The calculated maximum adsorbed amounts of AFB1 by MONT (40.982mg/g) and Cu-MONT (66.225mg/g), derived from Langmuir plots of isotherms, indicate that Cu-MONT was much effective in adsorbing AFB1. Since, the main cation in an exchangeable position in MONT is calcium, and in Cu-MONT both calcium and copper, the fact that ion exchange of inorganic cations in MONT with copper increases adsorption of AFB1 suggests that additional interactions between AFB1 and copper ions in Cu-MONT caused greater adsorption.
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Affiliation(s)
- Aleksandra Daković
- Institute for Technology of Nuclear and Other Mineral Raw Materials, 11 000 Belgrade, Serbia.
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20
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Eren E, Afsin B. An investigation of Cu(II) adsorption by raw and acid-activated bentonite: a combined potentiometric, thermodynamic, XRD, IR, DTA study. JOURNAL OF HAZARDOUS MATERIALS 2008; 151:682-91. [PMID: 17644249 DOI: 10.1016/j.jhazmat.2007.06.040] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 06/12/2007] [Accepted: 06/12/2007] [Indexed: 05/16/2023]
Abstract
Adsorption of Cu(II) by raw bentonite (RB) and acid-activated bentonite (AAB) samples was investigated as a function of the initial Cu(II) concentration, solution pH, ionic strength, temperature, the competitive and complexation effects of ligands (Cl-, SO4(2-), PO4(3-)). Langmuir monolayer adsorption capacity of the RB (42.41 mg g(-1)) was found greater than that of the AAB (32.17 mg g(-1)). The effect of structural charges on the reactivity of the edge groups was evidenced by the particular proton adsorption behaviour of the bentonite samples. The spontaneity of the adsorption process is established by decrease in DeltaG which varied from -0.34 to -0.71 kJ mol(-1) (RB), -1.13 to -1.49 kJ mol(-1) (AAB) in temperature range 303-313 K. Infrared (IR) spectra of the bentonite samples showed that the positions and shapes of the fundamental vibrations of the OH and Si-O groups were influenced by the adsorbed Cu(II) cations. Differential thermal analysis (DTA) results showed that adsorbed Cu(II) cations have a great effect on the thermal behaviour of the bentonite samples. The X-ray diffraction (XRD) spectra indicated that the Cu(II) adsorption onto the bentonite samples led to changes in unit cell dimensions and symmetry of the parent bentonites.
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Affiliation(s)
- E Eren
- Department of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayis University, 55139 Kurupelit-Samsun, Turkey.
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21
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Rajesh N, Mishra BG, Pareek PK. Solid phase extraction of chromium(VI) from aqueous solutions by adsorption of its diphenylcarbazide complex on a mixed bed adsorbent (acid activated montmorillonite-silica gel) column. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 69:612-8. [PMID: 17604681 DOI: 10.1016/j.saa.2007.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2007] [Revised: 04/26/2007] [Accepted: 05/07/2007] [Indexed: 05/16/2023]
Abstract
A novel approach has been developed for the solid phase extraction of chromium(VI) based on the adsorption of its diphenylcarbazide complex on a mixture of acid activated montmorillonite (AAM)-silica gel column. The effect of various parameters such as acidity, stability of the column, sample volume, interfering ions, etc., were studied in detail. The adsorbed complex could be easily eluted using polyethylene glycol-sulfuric acid mixture and the concentration of chromium has been determined using visible spectrophotometry. The calibration graph was linear in the range 0-1microgmL(-1) chromium(VI) with a detection limit of 6microgL(-1). A highest preconcentration factor of 25 could be obtained for 250mL sample volume using glass wool as support for the mixed bed adsorbent. Chromium(VI) could be effectively separated from other ions such as nickel, copper, zinc, chloride, sulfate, nitrate, etc., and the method has been successfully applied to study the recovery of chromium in electroplating waste water and spiked water samples.
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Affiliation(s)
- N Rajesh
- Chemistry Group, Birla Institute of Technology and Science, Pilani 333031, India.
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22
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Shen W, He H, Zhu J, Yuan P, Frost RL. Grafting of montmorillonite with different functional silanes via two different reaction systems. J Colloid Interface Sci 2007; 313:268-73. [PMID: 17512531 DOI: 10.1016/j.jcis.2007.04.029] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 04/13/2007] [Accepted: 04/13/2007] [Indexed: 11/18/2022]
Abstract
Silane grafted montmorillonites were synthesized by using 3-aminopropyltriethoxysilane and trimethylchlorosilane via two different grafting reaction systems: (a) ethanol-water mixture and (b) vapor of silane. The resulting products were investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA). XRD patterns demonstrate that silane was intercalated into the montmorillonite gallery, as indicated by the increase of the basal spacing. The product prepared by vapor deposition has a larger basal spacing than that obtained from solution, due to the different extent of silane hydrolysis in various grafting systems. TGA curves indicate that the methyl groups penetrate into the siloxane clay are the primary reason for the decrease of the dehydroxylation temperature of the grafted products. 3-Aminopropyltriethoxysilane in the grafted montmorillonite adopts a bilayer arrangement while trimethylchlorosilane adopts a monolayer arrangement within the clay gallery.
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Affiliation(s)
- Wei Shen
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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23
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Xue W, He H, Zhu J, Yuan P. FTIR investigation of CTAB-Al-montmorillonite complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 67:1030-6. [PMID: 17289428 DOI: 10.1016/j.saa.2006.09.024] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Accepted: 09/20/2006] [Indexed: 05/13/2023]
Abstract
In this study, CTAB-Al-montmorillonite complexes were synthesized by pre-modifying montmorillonite using different concentrations of surfactant (resulting in different surfactant loadings and basal spacings), then pillaring the organoclays with hydroxy-Al cations. The resultant inorganic-organic montmorillonite complexes were characterized using FTIR, with a combination of XRD, TG and chemical analysis. This study indicates that the basal spacings of the CTAB-Al-montmorillonite complexes and the amounts of Al-contained pillars strongly depend on the surfactant loadings in the clay interlayer space, resulted from the mobility variation of the intercalated surfactants. During pillaring hydroxy-Al cations into clay interlayer space, part of the intercalated surfactants were removed, resulting in a decrease of the ordering of alkyl chains and the frequency shifts of Si(Al)-O, Si-O-Al and (M-O)(Td) stretching vibrations. The hydrophobicity of the CTAB-Al-montmorillonite complex also strongly depends on the surfactant loading whereas that of the CTAB-Al-montmorillonite complex is relative lower than that of the corresponding organoclay, indicated by the frequency shift of the vibrations corresponding to the sorbed water and their contents estimated by TG curves. With the decrease of the sorbed water content, the frequency of the band of H-O-H bending (nu(2)) shifts to higher frequency while the O-H stretching vibration (nu(1) and nu(3)) shifts to lower frequency, indicating that H(2)O is less hydrogen bonded. Meanwhile, the ordered conformations of the alkyl chains in CTAB-Al-montmorillonite complex decrease when compared with that of the corresponding organoclay.
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Affiliation(s)
- Weihong Xue
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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24
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He H, Zhou Q, Frost RL, Wood BJ, Duong LV, Kloprogge JT. A X-ray photoelectron spectroscopy study of HDTMAB distribution within organoclays. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:1180-8. [PMID: 16920389 DOI: 10.1016/j.saa.2006.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Accepted: 06/14/2006] [Indexed: 05/11/2023]
Abstract
X-ray photoelectron spectroscopy (XPS) in combination with X-ray diffraction (XRD) and high-resolution thermogravimetric analysis (HRTG) has been used to investigate the surfactant distribution within the organoclays prepared at different surfactant concentrations. This study demonstrates that the surfactant distribution within the organoclays depends strongly on the surfactant loadings. In the organoclays prepared at relative low surfactant concentrations, the surfactant cations mainly locate in the clay interlayer, whereas the surfactants occupy both the clay interlayer space and the interparticle pores in the organoclays prepared at high surfactant concentrations. This is in accordance with the dramatic pore volume decrease of organoclays compared to those of starting clays. XPS survey scans show that, at low surfactant concentration (<1.0CEC), the ion exchange between Na+ and HDTMA+ is dominant, whereas both cations and ion pairs occur in the organoclays prepared at high concentrations (>1.0CEC). High-resolution XPS spectra show that the modification of clay with surfactants has prominent influences on the binding energies of the atoms in both clays and surfactants, and nitrogen is the most sensitive to the surfactant distribution within the organoclays.
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Affiliation(s)
- Hongping He
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
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25
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Zhou Q, Frost RL, He H, Xi Y. Changes in the surfaces of adsorbed para-nitrophenol on HDTMA organoclay—The XRD and TG study. J Colloid Interface Sci 2007; 307:50-5. [PMID: 17161414 DOI: 10.1016/j.jcis.2006.11.016] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Revised: 11/07/2006] [Accepted: 11/08/2006] [Indexed: 11/29/2022]
Abstract
Surfactant modified montmorillonitic clays synthesized by ion exchange using the hydrothermal reaction method have been compared using XRD and thermal analysis. X-ray diffraction (XRD) shows the changes in the surface properties of organoclays through expansion with surfactant loading. A polynomial relationship exists between the basal spacing and the CEC loading described by the equation y=0.3232x(2) + 0.2052x+1.2834 with R(2)=0.9955. Different arrangements of the surfactant molecules in the organoclays are inferred from the changes in basal spacings. para-Nitrophenol also causes the expansion of the montmorillonite clay and affects the arrangements of the surfactant molecules within the clay layers. Changes in the surfactant molecular arrangements were analyzed by thermogravimetry. Additional thermal decomposition steps were observed when para-nitrophenol is adsorbed on the organoclay.
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Affiliation(s)
- Qin Zhou
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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26
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Kloprogge JT, Mahmutagic E, Frost RL. Mid-infrared and infrared emission spectroscopy of Cu-exchanged montmorillonite. J Colloid Interface Sci 2006; 296:640-6. [PMID: 16239011 DOI: 10.1016/j.jcis.2005.09.055] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Revised: 09/23/2005] [Accepted: 09/23/2005] [Indexed: 11/20/2022]
Abstract
Middle Infrared Spectroscopy (Mid-IR) and Infrared Emission Spectroscopy (IES) were employed to characterise Cu-exchanged montmorillonites, which were derived from two different types of montmorillonite clays, Ca-exchanged montmorillonite (Cheto clay) and Na-exchanged montmorillonite (Miles clay). Copper was exchanged under both acidic and basic conditions at different Cu/clay ratios. All Cu-exchanged montmorillonites experienced a shift in most of non-lattice bands, with hydroxyl bands playing a major role in the characterisation of the clays. Furthermore, a relationship between the ratio of bands at 3630 and 3500 cm(-1) and the Cu concentration of the starting solutions was indicated and used to compare the degree of cation exchange between two preparation methods. Two dehydration stages were observed in the IES experiments. Additional bands were observed in all Cu-exchanged montmorillonites prepared with the 'basic conditions method,' and these bands were assigned to ammonia molecules trapped within the clay structure or absorbed on the surface of the clay.
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Affiliation(s)
- J Theo Kloprogge
- Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Q 4001, Australia.
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He H, Yang D, Yuan P, Shen W, Frost RL. A novel organoclay with antibacterial activity prepared from montmorillonite and Chlorhexidini Acetas. J Colloid Interface Sci 2005; 297:235-43. [PMID: 16309695 DOI: 10.1016/j.jcis.2005.10.031] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 10/04/2005] [Accepted: 10/04/2005] [Indexed: 11/20/2022]
Abstract
A series of novel organoclays with antibacterial activity were synthesized using Ca-montmorillonite and Chlorhexidini Acetas (CA) by ion-exchange. The resultant organoclays were characterized using X-ray diffraction (XRD), high-resolution thermogravimetric analysis (HRTG) and Fourier transform infrared spectroscopy (FTIR). Their antibacterial activity was assayed by so-called halo method. In the organoclays prepared at low CA concentration, CA ions within the clay interlayer adopt a lateral monolayer while a 'kink' state or a special state with partial overlapping of the intercalated CA in the organoclays prepared at 1.0-4.0 CEC. HRTG analysis demonstrates that CA located outside the clay interlayer exists in all synthesized organoclays, resulting from the complex molecular configuration of CA. The dramatic decrease of the surface adsorbed water and interlayer water is caused by the surface property transformation and the replacement of hydrated cations by cationic surfactant. These observations are supported by the results of FTIR. Antibacterial activity test against E. coli demonstrates that the antibacterial activity of the resultant organoclays strongly depends on the content of CA. Meanwhile, the resultant organoclay shows a long-term antibacterial activity that can last for at least one year. These novel organoclays are of potential use in synthesis of organoclay-based materials with antibacterial activity.
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Affiliation(s)
- Hongping He
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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28
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Tong G, Yulong M, Peng G, Zirong X. Antibacterial effects of the Cu(II)-exchanged montmorillonite on Escherichia coli K88 and Salmonella choleraesuis. Vet Microbiol 2004; 105:113-22. [PMID: 15627522 DOI: 10.1016/j.vetmic.2004.11.003] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2003] [Revised: 09/23/2004] [Accepted: 11/03/2004] [Indexed: 11/24/2022]
Abstract
The aim of this research was to determine the antibacterial properties and mechanisms of Cu(II)-exchanged montmorillonite (MMT-Cu) in vitro. Escherichia coli ATCC K88 and Salmonella choleraesuis ATCC 50020 were chosen as indicators of intestinal tract pathogenic bacteria in weanling pigs. The antibacterial activity of MMT-Cu and MMT were evaluated by determining the minimum inhibitory concentrations (MICs) using two-fold serial dilutions in MH broth, and the amount of Cu2+ released into the broth was measured by an atomic absorption technique. The rate of oxygen consumption was measured using a SP-II-type oxygen electrode analyzer; the structural integrity of cell walls of bacteria was observed by transmission electron microscope (TEM); enzymatic activity of bacteria was examined with a semi-automatic biochemical analyzer. The results showed that MMT-Cu inhibited the growth of E. coli K88 and S. choleraesuis, and the MICs were 1024 and 2048 microg/ml, respectively. The amount of Cu2+ released into the broth was in the range 6.51-45.65 microg/ml. Nevertheless, both tested bacteria still grew in broth containing 32,768 microg/ml of MMT. Treatment with MMT-Cu could lead to significant release of intracellular enzymes from the tested bacteria. Data from oxygen consumption of bacteria showed that MMT-Cu could inhibit the TCA pathway of the bacterial respiration metabolism. These results show that MMT-Cu has an antibacterial activity.
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Affiliation(s)
- Guo Tong
- College of Aqua-life Science & Technology, Shanghai Fisheries University, Shanghai 200090, China.
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29
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Stackhouse S, Coveney PV. Study of Thermally Treated Lithium Montmorillonite by Ab Initio Methods. J Phys Chem B 2002. [DOI: 10.1021/jp025883q] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stephen Stackhouse
- Centre for Computational Science, Department of Chemistry, Queen Mary, University of London, Mile End Road, London, E1 4NS, United Kingdom
| | - Peter V. Coveney
- Centre for Computational Science, Department of Chemistry, Queen Mary, University of London, Mile End Road, London, E1 4NS, United Kingdom
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