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Lu C, Hu C, Chen Z, Wang P, Feng F, He G, Wang F, Zhang Y, Liu JZ, Zhang X, Qu J. Dehydration-enhanced ion-pore interactions dominate anion transport and selectivity in nanochannels. SCIENCE ADVANCES 2023; 9:eadf8412. [PMID: 37418527 PMCID: PMC10328398 DOI: 10.1126/sciadv.adf8412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 06/06/2023] [Indexed: 07/09/2023]
Abstract
State-of-the-art ion-selective membranes with ultrahigh precision are of significance for water desalination and energy conservation, but their development is limited by the lack of understanding of the mechanisms of ion transport at the subnanometer scale. Herein, we investigate transport of three typical anions (F-, Cl-, and Br-) under confinement using in situ liquid time-of-flight secondary ion mass spectrometry in combination with transition-state theory. The operando analysis reveals that dehydration and related ion-pore interactions govern anion-selective transport. For strongly hydrated ions [(H2O)nF- and (H2O)nCl-], dehydration enhances ion effective charge and thus the electrostatic interactions with membrane, observed as an increase in decomposed energy from electrostatics, leading to more hindered transport. Contrarily, weakly hydrated ions [(H2O)nBr-] have greater permeability as they allow an intact hydration structure during transport due to their smaller size and the most right-skewed hydration distribution. Our work demonstrates that precisely regulating ion dehydration to maximize the difference in ion-pore interactions could enable the development of ideal ion-selective membranes.
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Affiliation(s)
- Chenghai Lu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chengzhi Hu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhibin Chen
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peiyao Wang
- Department of Mechanical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Fan Feng
- Department of Mechanical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Guangzhi He
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fuyi Wang
- University of Chinese Academy of Sciences, Beijing 100049, China
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Yanyan Zhang
- University of Chinese Academy of Sciences, Beijing 100049, China
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Jefferson Zhe Liu
- Department of Mechanical Engineering, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Xiwang Zhang
- UQ Dow Centre for Sustainable Engineering Innovation, School of Chemical Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Jiuhui Qu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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2
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Tekinalp Ö, Zimmermann P, Holdcroft S, Burheim OS, Deng L. Cation Exchange Membranes and Process Optimizations in Electrodialysis for Selective Metal Separation: A Review. MEMBRANES 2023; 13:566. [PMID: 37367770 DOI: 10.3390/membranes13060566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023]
Abstract
The selective separation of metal species from various sources is highly desirable in applications such as hydrometallurgy, water treatment, and energy production but also challenging. Monovalent cation exchange membranes (CEMs) show a great potential to selectively separate one metal ion over others of the same or different valences from various effluents in electrodialysis. Selectivity among metal cations is influenced by both the inherent properties of membranes and the design and operating conditions of the electrodialysis process. The research progress and recent advances in membrane development and the implication of the electrodialysis systems on counter-ion selectivity are extensively reviewed in this work, focusing on both structure-property relationships of CEM materials and influences of process conditions and mass transport characteristics of target ions. Key membrane properties, such as charge density, water uptake, and polymer morphology, and strategies for enhancing ion selectivity are discussed. The implications of the boundary layer at the membrane surface are elucidated, where differences in the mass transport of ions at interfaces can be exploited to manipulate the transport ratio of competing counter-ions. Based on the progress, possible future R&D directions are also proposed.
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Affiliation(s)
- Önder Tekinalp
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| | - Pauline Zimmermann
- Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| | - Steven Holdcroft
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Odne Stokke Burheim
- Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
| | - Liyuan Deng
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
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3
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Allouzi M, Imbrogno A, Schäfer AI. Energy Barriers for Steroid Hormone Transport in Nanofiltration. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:16811-16821. [PMID: 36367435 DOI: 10.1021/acs.est.2c04658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nanofiltration (NF) membranes can retain micropollutants (MPs) to a large extent, even though adsorption into the membrane and gradual permeation result in breakthrough and incomplete removal. The permeation of MPs is investigated by examining the energy barriers (determined using the Arrhenius concept) for adsorption, intrapore diffusion, and permeation encountered by four different steroid hormones in tight and loose NF membranes. Results show that the energy barriers for steroid hormone transport in tight membrane are entropically dominated and underestimated because of the high steric exclusion at the pore entrance. In contrast, the loose NF membrane enables steroid hormones partitioning at the pore entrance, with a permeation energy barrier (from feed toward the permeate side) ranging between 96 and 116 kJ/mol. The contribution of adsorption and intrapore diffusion to the energy barrier for steroid hormone permeation reveals a significant role of intrapore diffusive transport on the obtained permeation energy barrier. Overall, the breakthrough phenomenon observed during the NF of MPs is facilitated by the low energy barrier for adsorption. Experimental evidence of such principles is relevant for understanding mechanisms and ultimately improving the selectivity of NF.
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Affiliation(s)
- Mohammad Allouzi
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344Eggenstein-Leopoldshafen, Germany
| | - Alessandra Imbrogno
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344Eggenstein-Leopoldshafen, Germany
| | - Andrea I Schäfer
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344Eggenstein-Leopoldshafen, Germany
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4
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Leisle L, Lam K, Dehghani-Ghahnaviyeh S, Fortea E, Galpin JD, Ahern CA, Tajkhorshid E, Accardi A. Backbone amides are determinants of Cl - selectivity in CLC ion channels. Nat Commun 2022; 13:7508. [PMID: 36473856 PMCID: PMC9726985 DOI: 10.1038/s41467-022-35279-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 11/23/2022] [Indexed: 12/12/2022] Open
Abstract
Chloride homeostasis is regulated in all cellular compartments. CLC-type channels selectively transport Cl- across biological membranes. It is proposed that side-chains of pore-lining residues determine Cl- selectivity in CLC-type channels, but their spatial orientation and contributions to selectivity are not conserved. This suggests a possible role for mainchain amides in selectivity. We use nonsense suppression to insert α-hydroxy acids at pore-lining positions in two CLC-type channels, CLC-0 and bCLC-k, thus exchanging peptide-bond amides with ester-bond oxygens which are incapable of hydrogen-bonding. Backbone substitutions functionally degrade inter-anion discrimination in a site-specific manner. The presence of a pore-occupying glutamate side chain modulates these effects. Molecular dynamics simulations show backbone amides determine ion energetics within the bCLC-k pore and how insertion of an α-hydroxy acid alters selectivity. We propose that backbone-ion interactions are determinants of Cl- specificity in CLC channels in a mechanism reminiscent of that described for K+ channels.
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Affiliation(s)
- Lilia Leisle
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA
| | - Kin Lam
- Theoretical and Computational Biophysics Group, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- NIH Center for Macromolecular Modeling and Bioinformatics, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Sepehr Dehghani-Ghahnaviyeh
- Theoretical and Computational Biophysics Group, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- NIH Center for Macromolecular Modeling and Bioinformatics, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Eva Fortea
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY, USA
| | - Jason D Galpin
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | - Christopher A Ahern
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA
| | - Emad Tajkhorshid
- Theoretical and Computational Biophysics Group, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- NIH Center for Macromolecular Modeling and Bioinformatics, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
- Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Alessio Accardi
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, USA.
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY, USA.
- Department of Biochemistry, Weill Cornell Medical College, New York, NY, USA.
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5
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Arya V, Chaudhuri A, Bakli C. Coupling solute interactions with functionalized graphene membranes: towards facile membrane-level engineering. NANOSCALE 2022; 14:16661-16672. [PMID: 36330851 DOI: 10.1039/d2nr05552j] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Optimizing ion transport through nanoporous graphene membranes with intricate engineering at nanoscale levels finds applications ranging from ion segregation to desalination. Such membrane-level engineering often requires futuristic and state-of-the-art micro- and nanofabrication infrastructure making it less accessible to widespread applications. In this study, the effective membrane pore size is modulated using macroscopic membrane functionalization, which, when combined with the solute concentration, can prove to be facile nanoscale engineering towards achieving selectivity. By performing robust molecular dynamics (MD) simulations of aqueous NaCl solution through a nanoporous graphene membrane, we demonstrate that varying membrane wettability influences the structural organization of ions and water molecules both in the vicinity and inside the nanopore, which is manifested in the form of altered permeation characteristics. Moreover, the disparate solvation characteristics of the ionic species in conjunction with the variable van der Waals interactive forces affect the ion-selective nature (Cl- over Na+) of the membrane. The relative hydrophilization, resulting from the effective functionalization of the nanoporous graphene membrane, not only allows greater control over the permeation characteristics of ions and water molecules mediated by an altered depletion ratio but also gives rise to the ion-selective nature of the membrane, thus providing a sound understanding of the transport properties of ion-water solutions through nanoporous materials.
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Affiliation(s)
- Vinay Arya
- School of Energy Science and Engineering, Indian Institute of Technology Kharagpur, India.
| | - Abhirup Chaudhuri
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, India
| | - Chirodeep Bakli
- School of Energy Science and Engineering, Indian Institute of Technology Kharagpur, India.
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6
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Zhai X, Wang YL, Dai R, Li X, Wang Z. Roles of Anion-Cation Coupling Transport and Dehydration-Induced Ion-Membrane Interaction in Precise Separation of Ions by Nanofiltration Membranes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:14069-14079. [PMID: 36126287 DOI: 10.1021/acs.est.2c04772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Nanofiltration (NF) membranes are playing increasingly crucial roles in addressing emerging environmental challenges by precise separation, yet understanding of the selective transport mechanism is still limited. In this work, the underlying mechanisms governing precise selectivity of the polyamide NF membrane were elucidated using a series of monovalent cations with minor hydrated radius difference. The observed selectivity of a single cation was neither correlated with the hydrated radius nor hydration energy, which could not be explained by the widely accepted NF model or ion dehydration theory. Herein, we employed an Arrhenius approach combined with Monte Carlo simulation to unravel that the transmembrane process of the cation would be dominated by its pairing anion, if the anion has a greater transmembrane energy barrier, due to the constraint of anion-cation coupling transport. Molecular dynamics simulations further revealed that the distinct hydration structure was the primary origin of the energy barrier difference of cations. The cation having a larger incompressible structure after partial dehydration through subnanopores would induce a more significant ion-membrane interaction and consequently a higher energy barrier. Moreover, to validate our proposed mechanisms, a membrane grafting modification toward enlarging the energy barrier difference of dominant ions achieved a 3-fold enhancement in ion separation efficiency. Our work provides insights into the precise separation of ionic species by NF membranes.
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Affiliation(s)
- Xiaohu Zhai
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji Advanced Membrane Technology Center, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yong-Lei Wang
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm SE-106 91, Sweden
| | - Ruobin Dai
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji Advanced Membrane Technology Center, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xuesong Li
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji Advanced Membrane Technology Center, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, Tongji Advanced Membrane Technology Center, School of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
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7
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Selectivity of artificial water channel-polyamide composite membranes towards inorganic contaminants. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.121019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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8
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Wordsworth J, Benedetti TM, Somerville SV, Schuhmann W, Tilley RD, Gooding JJ. The Influence of Nanoconfinement on Electrocatalysis. Angew Chem Int Ed Engl 2022; 61:e202200755. [PMID: 35403340 PMCID: PMC9401583 DOI: 10.1002/anie.202200755] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Indexed: 01/02/2023]
Abstract
The use of nanoparticles and nanostructured electrodes are abundant in electrocatalysis. These nanometric systems contain elements of nanoconfinement in different degrees, depending on the geometry, which can have a much greater effect on the activity and selectivity than often considered. In this Review, we firstly identify the systems containing different degrees of nanoconfinement and how they can affect the activity and selectivity of electrocatalytic reactions. Then we follow with a fundamental understanding of how electrochemistry and electrocatalysis are affected by nanoconfinement, which is beginning to be uncovered, thanks to the development of new, atomically precise manufacturing and fabrication techniques as well as advances in theoretical modeling. The aim of this Review is to help us look beyond using nanostructuring as just a way to increase surface area, but also as a way to break the scaling relations imposed on electrocatalysis by thermodynamics.
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Affiliation(s)
- Johanna Wordsworth
- School of Chemistry, Australian Centre for NanoMedicine, University of New South Wales, Sydney, 2052, Australia
| | - Tania M Benedetti
- School of Chemistry, Australian Centre for NanoMedicine, University of New South Wales, Sydney, 2052, Australia
| | - Samuel V Somerville
- School of Chemistry, Australian Centre for NanoMedicine, University of New South Wales, Sydney, 2052, Australia
| | - Wolfgang Schuhmann
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätstrasse 150, 44780, Bochum, Germany
| | - Richard D Tilley
- Electron Microscope Unit, Mark Wainwright Analytical Centre, University of New South Wales, Sydney, 2052, Australia
| | - J Justin Gooding
- School of Chemistry, Australian Centre for NanoMedicine, University of New South Wales, Sydney, 2052, Australia
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9
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Shefer I, Lopez K, Straub AP, Epsztein R. Applying Transition-State Theory to Explore Transport and Selectivity in Salt-Rejecting Membranes: A Critical Review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:7467-7483. [PMID: 35549171 DOI: 10.1021/acs.est.2c00912] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Membrane technologies using reverse osmosis (RO) and nanofiltration (NF) have been widely implemented in water purification and desalination processes. Separation between species at the molecular level is achievable in RO and NF membranes due to a complex and poorly understood combination of transport mechanisms that have attracted the attention of researchers within and beyond the membrane community for many years. Minimizing existing knowledge gaps in transport through these membranes can improve the sustainability of current water-treatment processes and expand the use of RO and NF membranes to other applications that require high selectivity between species. Since its establishment in 1949, and with growing popularity in recent years, Eyring's transition-state theory (TST) for transmembrane permeation has been applied in numerous studies to mechanistically explore molecular transport in membranes including RO and NF. In this review, we critically assess TST applied to transmembrane permeation in salt-rejecting membranes, focusing on mechanistic insights into transport under confinement that can be gained from this framework and the key limitations associated with the method. We first demonstrate and discuss the limited ability of the commonly used solution-diffusion model to mechanistically explain transport and selectivity trends observed in RO and NF membranes. Next, we review important milestones in the development of TST, introduce its underlying principles and equations, and establish the connection to transmembrane permeation with a focus on molecular-level enthalpic and entropic barriers that govern water and solute transport under confinement. We then critically review the application of TST to explore transport in RO and NF membranes, analyzing trends in measured enthalpic and entropic barriers and synthesizing new data to highlight important phenomena associated with the temperature-dependent measurement of the activation parameters. We also discuss major limitations of the experimental application of TST and propose specific solutions to minimize the uncertainties surrounding the current approach. We conclude with identifying future research needs to enhance the implementation and maximize the benefit of TST application to transmembrane permeation.
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Affiliation(s)
- Idit Shefer
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa 32000, Israel
| | - Kian Lopez
- Department of Civil, Environmental and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado 80309-0428, United States
| | - Anthony P Straub
- Department of Civil, Environmental and Architectural Engineering, University of Colorado Boulder, Boulder, Colorado 80309-0428, United States
| | - Razi Epsztein
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa 32000, Israel
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10
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Yong H, He X, Merlitz H. Connection between Intrapore Free Energy, Molecule Permeation, and Selectivity of Nanofiltration Membranes. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Huaisong Yong
- Department of Polymer Materials and Engineering, School of New Energy and Materials, Southwest Petroleum University, 610500, Chengdu, China
- Institute Theory of Polymers, Leibniz-Institut für Polymerforschung Dresden e.V., D-01069, Dresden, Germany
| | - Xianru He
- Department of Polymer Materials and Engineering, School of New Energy and Materials, Southwest Petroleum University, 610500, Chengdu, China
| | - Holger Merlitz
- Institute Theory of Polymers, Leibniz-Institut für Polymerforschung Dresden e.V., D-01069, Dresden, Germany
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11
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Wordsworth J, Benedetti TM, Somerville SV, Schuhmann W, Tilley RD, Gooding JJ. The Influence of Nanoconfinement on Electrocatalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200755] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Wolfgang Schuhmann
- Ruhr-Universitat Bochum Analytische Chemie Universitätsstr 150 44780 Bochum GERMANY
| | - Richard D. Tilley
- UNSW: University of New South Wales Electron Microscopy Unit AUSTRALIA
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12
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Li S, Mubashar M, Qin Y, Nie X, Zhang X. Aquaculture waste nutrients removal using microalgae with floating permeable nutrient uptake system (FPNUS). BIORESOURCE TECHNOLOGY 2022; 347:126338. [PMID: 34800641 DOI: 10.1016/j.biortech.2021.126338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 11/06/2021] [Accepted: 11/09/2021] [Indexed: 06/13/2023]
Abstract
Large area requirements and huge energy consumption restrict the applications of microalgae in wastewater treatment. In this study, in-situ nutrient removal was tested using a floating permeable nutrients uptake system with pore sizes of 1, 5, 10, and 40 µm, and Chlorella sorokiniana and Scenedesmus acuminatus. Results showed that N transfer rate across FPNUS varied with membrane pore size and N-type. Average transfer rate of NH4+-N, NO3--N, and NO2--N across 1 µm membrane was 2.6, 14.6, and 2.3 mg m-2h-1, respectively, sufficient to support microalgal growth. The NH4+-N and NO3--N removal rate in shrimp wastewater reached 1.32 and 1.88 mg L-1d-1, comparable to some BNR processes used in RAS. According to the developed area ratio prediction model, FPNUS to pond area ratio of 21% is sufficient to balance N loading of 0.05 mg L-1d-1. These results indicate extraordinary potential of in-situ nutrient removal from wastewaters using FPNUS.
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Affiliation(s)
- Shouchun Li
- College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China
| | - Muhammad Mubashar
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yufeng Qin
- College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China
| | - Xifan Nie
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuezhi Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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13
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Pavluchkov V, Shefer I, Peer-Haim O, Blotevogel J, Epsztein R. Indications of ion dehydration in diffusion-only and pressure-driven nanofiltration. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.120358] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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14
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Shefer I, Peer-Haim O, Leifman O, Epsztein R. Enthalpic and Entropic Selectivity of Water and Small Ions in Polyamide Membranes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:14863-14875. [PMID: 34677944 DOI: 10.1021/acs.est.1c04956] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
While polyamide reverse osmosis and nanofiltration membranes have been extensively utilized in water purification and desalination processes, the molecular details governing water and solute permeation in these membranes are not fully understood. In this study, we apply transition-state theory for transmembrane permeation to systematically break down the intrinsic permeabilities of water and small ions in loose and tight polyamide nanofiltration membranes into enthalpic and entropic components using an Eyring-type equation. We analyze trends in these components to elucidate molecular phenomena that induce water-salt, monovalent-divalent, and monovalent-monovalent selectivity at different pH values. Our results suggest that in pores that are either too small or contain an electrostatically repelling mouth, the thermal activation of ions in the form of ion dehydration is less likely, promoting entropically driven selectivity with steric exclusion of hydrated ions. Instead, larger uncharged pores enable ion dehydration, inducing enthalpic selectivity that is driven by differences in the ion hydration properties. We also demonstrate that electrostatic interactions between cations and intrapore carboxyl groups hinder salt permeability, increasing the enthalpic barrier of the transport. Last, permeation tests of monovalent cations in the loose and tight polyamide membranes expose opposite rejection trends that further support the phenomenon of ion dehydration in large subnanopores.
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Affiliation(s)
- Idit Shefer
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Ophir Peer-Haim
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Olga Leifman
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Razi Epsztein
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel
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15
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Preparation of monovalent cation perm-selective membranes by controlling surface hydration energy barrier. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.118768] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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16
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Xu Z, He Z, Quan X, Sun D, Miao Z, Yu H, Yang S, Chen Z, Zeng J, Zhou J. Molecular simulations of charged complex fluids: A review. Chin J Chem Eng 2021. [DOI: 10.1016/j.cjche.2020.11.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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Bhardwaj AA, Vos JG, Beatty MES, Baxter AF, Koper MTM, Yip NY, Esposito DV. Ultrathin Silicon Oxide Overlayers Enable Selective Oxygen Evolution from Acidic and Unbuffered pH-Neutral Seawater. ACS Catal 2021. [DOI: 10.1021/acscatal.0c04343] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Amar A. Bhardwaj
- Department of Chemical Engineering, Columbia Electrochemical Engineering Center, Lenfest Center for Sustainable Energy, Columbia University in the City of New York, 500 West 120th Street, New York, New York 10027, United States
| | - Johannes G. Vos
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Marissa E. S. Beatty
- Department of Chemical Engineering, Columbia Electrochemical Engineering Center, Lenfest Center for Sustainable Energy, Columbia University in the City of New York, 500 West 120th Street, New York, New York 10027, United States
| | - Amanda F. Baxter
- Department of Chemical Engineering, Columbia Electrochemical Engineering Center, Lenfest Center for Sustainable Energy, Columbia University in the City of New York, 500 West 120th Street, New York, New York 10027, United States
| | - Marc T. M. Koper
- Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Ngai Yin Yip
- Department of Earth and Environmental Engineering, Columbia Water Center, Columbia University in the City of New York, 500 West 120th Street, New York, New York 10027, United States
| | - Daniel V. Esposito
- Department of Chemical Engineering, Columbia Electrochemical Engineering Center, Lenfest Center for Sustainable Energy, Columbia University in the City of New York, 500 West 120th Street, New York, New York 10027, United States
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18
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Zhou X, Wang Z, Epsztein R, Zhan C, Li W, Fortner JD, Pham TA, Kim JH, Elimelech M. Intrapore energy barriers govern ion transport and selectivity of desalination membranes. SCIENCE ADVANCES 2020; 6:6/48/eabd9045. [PMID: 33239305 PMCID: PMC7688318 DOI: 10.1126/sciadv.abd9045] [Citation(s) in RCA: 113] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/09/2020] [Indexed: 05/03/2023]
Abstract
State-of-the-art desalination membranes exhibit high water-salt selectivity, but their ability to discriminate between ions is limited. Elucidating the fundamental mechanisms underlying ion transport and selectivity in subnanometer pores is therefore imperative for the development of ion-selective membranes. Here, we compare the overall energy barrier for salt transport and energy barriers for individual ion transport, showing that cations and anions traverse the membrane pore in an independent manner. Supported by density functional theory simulations, we demonstrate that electrostatic interactions between permeating counterion and fixed charges on the membrane substantially hinder intrapore diffusion. Furthermore, using quartz crystal microbalance, we break down the contributions of partitioning at the pore mouth and intrapore diffusion to the overall energy barrier for salt transport. Overall, our results indicate that intrapore diffusion governs salt transport through subnanometer pores due to ion-pore wall interactions, providing the scientific base for the design of membranes with high ion-ion selectivity.
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Affiliation(s)
- Xuechen Zhou
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA
| | - Zhangxin Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA
| | - Razi Epsztein
- Faculty of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Cheng Zhan
- Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
| | - Wenlu Li
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA
| | - John D Fortner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA
| | - Tuan Anh Pham
- Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
| | - Jae-Hong Kim
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA.
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, USA.
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19
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Chu CH, Wang C, Xiao HF, Wang Q, Yang WJ, Liu N, Ju X, Xie JX, Sun SP. Separation of ions with equivalent and similar molecular weights by nanofiltration: Sodium chloride and sodium acetate as an example. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117199] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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20
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Yadav S, Chandra A. Transport of hydrated nitrate and nitrite ions through graphene nanopores in aqueous medium. J Comput Chem 2020; 41:1850-1858. [PMID: 32500955 DOI: 10.1002/jcc.26356] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 05/13/2020] [Accepted: 05/17/2020] [Indexed: 11/11/2022]
Abstract
Nitrate ( NO 3 - ) and nitrite ( NO 2 - ) ions are naturally occurring inorganic ions that are part of the nitrogen cycle. High doses of these ions in drinking water impose a potential risk to public health. In this work, molecular dynamics simulations are carried out to study the passage of nitrate and nitrite ions from water through graphene nanosheets (GNS) with hydrogen-functionalized narrow pores in presence of an external electric field. The passage of ions through the pores is investigated through calculations of ion flux, and the results are analyzed through calculations of various structural and thermodynamic properties such as the density of ions and water, ion-water radial distribution functions, two-dimensional density distribution functions, and the potentials of mean force of the ions. Current simulations show that the nitrite ions can pass more in numbers than the nitrate ions in a given time through GNS hydrogen-functionalized pore of different geometry. It is found that the nitrite ions can permeate faster than the nitrate ions despite the former having higher hydration energy in the bulk. This can be explained in terms of the competition between the number density of the ions along the pore axis and the free energy barrier calculated from the potential of mean force. Also, an externally applied electric field is found to be important for faster permeation of the nitrite over the nitrate ions. The current study suggests that graphene nanosheets with carefully created pores can be effective in achieving selective passage of ions from aqueous solutions.
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Affiliation(s)
- Sushma Yadav
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India.,International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Ibaraki, Japan
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh, India
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21
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Epsztein R, DuChanois RM, Ritt CL, Noy A, Elimelech M. Towards single-species selectivity of membranes with subnanometre pores. NATURE NANOTECHNOLOGY 2020; 15:426-436. [PMID: 32533116 DOI: 10.1038/s41565-020-0713-6] [Citation(s) in RCA: 239] [Impact Index Per Article: 59.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 05/12/2020] [Indexed: 05/12/2023]
Abstract
Synthetic membranes with pores at the subnanometre scale are at the core of processes for separating solutes from water, such as water purification and desalination. While these membrane processes have achieved substantial industrial success, the capability of state-of-the-art membranes to selectively separate a single solute from a mixture of solutes is limited. Such high-precision separation would enable fit-for-purpose treatment, improving the sustainability of current water-treatment processes and opening doors for new applications of membrane technologies. Herein, we introduce the challenges of state-of-the-art membranes with subnanometre pores to achieve high selectivity between solutes. We then analyse experimental and theoretical literature to discuss the molecular-level mechanisms that contribute to energy barriers for solute transport through subnanometre pores. We conclude by providing principles and guidelines for designing next-generation single-species selective membranes that are inspired by ion-selective biological channels.
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Affiliation(s)
- Razi Epsztein
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
- Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Ryan M DuChanois
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Cody L Ritt
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA
| | - Aleksandr Noy
- Materials Science Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA
- School of Natural Sciences, University of California Merced, Merced, CA, USA
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA.
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22
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Sigurdardottir SB, DuChanois RM, Epsztein R, Pinelo M, Elimelech M. Energy barriers to anion transport in polyelectrolyte multilayer nanofiltration membranes: Role of intra-pore diffusion. J Memb Sci 2020. [DOI: 10.1016/j.memsci.2020.117921] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Hussain S, Haji-Akbari A. Studying rare events using forward-flux sampling: Recent breakthroughs and future outlook. J Chem Phys 2020; 152:060901. [DOI: 10.1063/1.5127780] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Sarwar Hussain
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, USA
| | - Amir Haji-Akbari
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, USA
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24
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Epsztein R, Shaulsky E, Qin M, Elimelech M. Activation behavior for ion permeation in ion-exchange membranes: Role of ion dehydration in selective transport. J Memb Sci 2019. [DOI: 10.1016/j.memsci.2019.02.009] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Owusu-Agyeman I, Shen J, Schäfer AI. Renewable energy powered membrane technology: Impact of pH and ionic strength on fluoride and natural organic matter removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 621:138-147. [PMID: 29179069 DOI: 10.1016/j.scitotenv.2017.11.111] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 11/03/2017] [Accepted: 11/09/2017] [Indexed: 06/07/2023]
Abstract
Real water pH and ionic strength vary greatly, which influences the performance of membrane processes such as nanofiltration (NF) and reverse osmosis (RO). Systematic variation of pH (3-12) and ionic strength (2-10g/L as total dissolved solids (TDS)) was undertaken with a real Tanzanian water to investigate how water quality affects retention mechanisms of fluoride (F) and natural organic matter (NOM). An autonomous solar powered NF/RO system driven by a solar array simulator was supplied with constant power from a generator. An open NF (NF270) and a brackish water RO (BW30) membrane were used. A surface water with a very high F (59.7mg/L) and NOM (110mgC/L) was used. Retention of F by NF270 was <20% at pH <6, increased to 40% at pH6, and 60-70% at pH7-12, indicating a dominance of charge repulsion while being ineffective in meeting the guideline of 1.5mg/L. Increase in ionic strength led to a significant decline in retention of F (from 70 to 50%) and electrical conductivity (from 60 to 10%) by NF270, presumably due to charge screening. In contrast, BW30 retained about 50% of F at pH3, >80% at pH4, and about 99% at pH >5, due to the smaller pore size and hence a more dominant size exclusion. In consequence, only little impact of ionic strength increase was observed for BW30. The concentration of NOM in permeates of both NF270 and BW30 were typically <2mg/L. This was not affected by pH or ionic strength due to the fact that the bulk of NOM was rejected by both membranes through size exclusion. The research is carried out in the context of providing safe drinking water for rural and remote communities where infrastructure is lacking, and water quality varies significantly. While other studies focus on energy fluctuations, this research emphasises on feed water quality that affects system performance and may alter due to a number of environmental factors.
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Affiliation(s)
- Isaac Owusu-Agyeman
- Membrane Technology Department, Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Junjie Shen
- Department of Water and Environmental Engineering, Nelson Mandela African Institute of Science and Technology, Arusha, Tanzania; School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Andrea Iris Schäfer
- Membrane Technology Department, Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany; Department of Water and Environmental Engineering, Nelson Mandela African Institute of Science and Technology, Arusha, Tanzania.
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26
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Epsztein R, Shaulsky E, Dizge N, Warsinger DM, Elimelech M. Role of Ionic Charge Density in Donnan Exclusion of Monovalent Anions by Nanofiltration. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:4108-4116. [PMID: 29510032 DOI: 10.1021/acs.est.7b06400] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The main objective of this study is to examine how the charge densities of four monovalent anions-fluoride (F-), chloride (Cl-), bromide (Br-), and nitrate (NO3-)-influence their Donnan (charge) exclusion by a charged nanofiltration (NF) membrane. We systematically studied the rejection behavior of ternary ion solutions containing sodium cation (Na+) and two of the monovalent anions as a function of the pH with a polyamide NF membrane. In the solutions containing F- and Cl- or F- and Br-, F- rejection was higher than Cl- or Br- rejection only when the solution pH was higher than 5.5, suggesting that F- (which has a higher charge density) was repelled more strongly by the negatively charged membrane. The order of change in the activation energy for the transport of the four anions through the polyamide membrane as a response to the increase of the membrane negative charge was the following: F- > Cl- > NO3- > Br-. This order corroborates our main hypothesis that an anion with a smaller ionic radius, and hence a higher charge density, is more affected by the Donnan (charge)-exclusion mechanism in NF. We conclude with a proposed mechanism for the role of ionic charge density in the rejection of monovalent anions in NF.
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Affiliation(s)
- Razi Epsztein
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520-8286 , United States
| | - Evyatar Shaulsky
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520-8286 , United States
| | - Nadir Dizge
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520-8286 , United States
- Department of Environmental Engineering , Mersin University , Mersin 33343 , Turkey
| | - David M Warsinger
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520-8286 , United States
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520-8286 , United States
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27
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Sahu S, Zwolak M. Maxwell-Hall access resistance in graphene nanopores. Phys Chem Chem Phys 2018; 20:4646-4651. [PMID: 29400906 DOI: 10.1039/c7cp07924a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The resistance due to the convergence from bulk to a constriction, for example, a nanopore, is a mainstay of transport phenomena. In classical electrical conduction, Maxwell, and later Hall for ionic conduction, predicted this access or convergence resistance to be independent of the bulk dimensions and inversely dependent on the pore radius, a, for a perfectly circular pore. More generally, though, this resistance is contextual, it depends on the presence of functional groups/charges and fluctuations, as well as the (effective) constriction geometry/dimensions. Addressing the context generically requires all-atom simulations, but this demands enormous resources due to the algebraically decaying nature of convergence. We develop a finite-size scaling analysis, reminiscent of the treatment of critical phenomena, that makes the convergence resistance accessible in such simulations. This analysis suggests that there is a "golden aspect ratio" for the simulation cell that yields the infinite system result with a finite system. We employ this approach to resolve the experimental and theoretical discrepancies in the radius-dependence of graphene nanopore resistance.
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Affiliation(s)
- Subin Sahu
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
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28
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Epsztein R, Cheng W, Shaulsky E, Dizge N, Elimelech M. Elucidating the mechanisms underlying the difference between chloride and nitrate rejection in nanofiltration. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2017.10.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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29
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Shevkunov SV. High Temperature Stability of Hydrated Ion Pairs Na+Cl–(H2O) N under Conditions of a Flat Nanopore. RUSS J ELECTROCHEM+ 2018. [DOI: 10.1134/s1023193518020064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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30
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Tanaka H, Iizuka H, Pershin YV, Ventra MD. Surface effects on ionic Coulomb blockade in nanometer-size pores. NANOTECHNOLOGY 2018; 29:025703. [PMID: 29130892 DOI: 10.1088/1361-6528/aa9a14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ionic Coulomb blockade in nanopores is a phenomenon that shares some similarities but also differences with its electronic counterpart. Here, we investigate this phenomenon extensively using all-atom molecular dynamics of ionic transport through nanopores of about one nanometer in diameter and up to several nanometers in length. Our goal is to better understand the role of atomic roughness and structure of the pore walls in the ionic Coulomb blockade. Our numerical results reveal the following general trends. First, the nanopore selectivity changes with its diameter, and the nanopore position in the membrane influences the current strength. Second, the ionic transport through the nanopore takes place in a hopping-like fashion over a set of discretized states caused by local electric fields due to membrane atoms. In some cases, this creates a slow-varying 'crystal-like' structure of ions inside the nanopore. Third, while at a given voltage, the resistance of the nanopore depends on its length, the slope of this dependence appears to be independent of the molarity of ions. An effective kinetic model that captures the ionic Coulomb blockade behavior observed in MD simulations is formulated.
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Affiliation(s)
- Hiroya Tanaka
- Toyota Central Research & Development Labs. Inc., Nagakute, Aichi 480 1192, Japan
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31
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Thaunay F, Jana C, Clavaguéra C, Ohanessian G. Strategy for Modeling the Infrared Spectra of Ion-Containing Water Drops. J Phys Chem A 2018; 122:832-842. [PMID: 29266957 DOI: 10.1021/acs.jpca.7b10554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrated ions are ubiquitous in environmental and biological media. Understanding the perturbation exerted by an ion on the water hydrogen bond network is possible in the nanodrop regime by recording vibrational spectra in the O-H bond stretching region. This has been achieved experimentally in recent years by forming gaseous ions containing tens to hundreds of water molecules and recording their infrared photodissociation spectra. In this paper, we demonstrate the capabilities of a modeling strategy based on an extension of the AMOEBA polarizable force field to implement water atomic charge fluctuations along with those of intramolecular structure along the dynamics. This supplementary flexibility of nonbonded interactions improves the description of the hydrogen bond network and, therefore, the spectroscopic response. Finite temperature IR spectra are obtained from molecular dynamics simulations by computing the Fourier transform of the dipole moment autocorrelation function. Simulations of 1-2 ns are required for extensive sampling in order to reproduce the experimental spectra. Furthermore, bands are assigned with the driven molecular dynamics approach. This method package is shown to compare successfully with experimental spectra for 11 ions in water drops containing 36-100 water molecules. In particular, band frequency shifts of the free O-H stretching modes at the cluster surface are well reproduced as a function of both ion charge and drop size.
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Affiliation(s)
- Florian Thaunay
- LCM, CNRS, Ecole Polytechnique, Université Paris Saclay , 91128 Palaiseau, France
| | - Chandramohan Jana
- LCM, CNRS, Ecole Polytechnique, Université Paris Saclay , 91128 Palaiseau, France
| | - Carine Clavaguéra
- Laboratoire de Chimie Physique, Université Paris Sud - CNRS, Université Paris Saclay , 15, avenue Jean Perrin, 91405 Orsay Cedex, France
| | - Gilles Ohanessian
- LCM, CNRS, Ecole Polytechnique, Université Paris Saclay , 91128 Palaiseau, France
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32
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Sahu S, Zwolak M. Ionic selectivity and filtration from fragmented dehydration in multilayer graphene nanopores. NANOSCALE 2017; 9:11424-11428. [PMID: 28767109 PMCID: PMC5604754 DOI: 10.1039/c7nr03838k] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Selective ion transport is a hallmark of biological ion channel behavior but is a major challenge to engineer into artificial membranes. Here, we demonstrate, with all-atom molecular dynamics simulations, that bare graphene nanopores yield measurable ion selectivity that varies over one to two orders of magnitude simply by changing the pore radius and number of graphene layers. Monolayer graphene does not display dehydration-induced selectivity until the pore radius is small enough to exclude the first hydration layer from inside the pore. Bi- and tri-layer graphene, though, display such selectivity already for a pore size that barely encroaches on the first hydration layer, which is due to the more significant water loss from the second hydration layer. Measurement of selectivity and activation barriers from both first and second hydration layer barriers will help elucidate the behavior of biological ion channels. Moreover, the energy barriers responsible for selectivity - while small on the scale of hydration energies - are already relatively large, i.e., many kBT. For separation of ions from water, therefore, one can exchange longer, larger radius pores for shorter, smaller radius pores, giving a practical method for maintaining exclusion efficiency while enhancing other properties (e.g., water throughput).
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Affiliation(s)
- Subin Sahu
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
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33
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Sahu S, Di Ventra M, Zwolak M. Dehydration as a Universal Mechanism for Ion Selectivity in Graphene and Other Atomically Thin Pores. NANO LETTERS 2017; 17:4719-4724. [PMID: 28678508 PMCID: PMC5614503 DOI: 10.1021/acs.nanolett.7b01399] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Ion channels play a key role in regulating cell behavior and in electrical signaling. In these settings, polar and charged functional groups, as well as protein response, compensate for dehydration in an ion-dependent way, giving rise to the ion selective transport critical to the operation of cells. Dehydration, though, yields ion-dependent free-energy barriers and thus is predicted to give rise to selectivity by itself. However, these barriers are typically so large that they will suppress the ion currents to undetectable levels. Here, we establish that graphene displays a measurable dehydration-only mechanism for selectivity of K+ over Cl-. This fundamental mechanism, one that depends only on the geometry and hydration, is the starting point for selectivity for all channels and pores. Moreover, while we study selectivity of K+ over Cl- we find that dehydration-based selectivity functions for all ions, that is, cation over cation selectivity (e.g., K+ over Na+). Its likely detection in graphene pores resolves conflicting experimental results, as well as presents a new paradigm for characterizing the operation of ion channels and engineering molecular/ionic selectivity in filtration and other applications.
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Affiliation(s)
- Subin Sahu
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
- Maryland Nanocenter, University of Maryland , College Park, Maryland 20742, United States
- Department of Physics, Oregon State University , Corvallis, Oregon 97331, United States
| | - Massimiliano Di Ventra
- Department of Physics, University of California , San Diego, California 92093, United States
| | - Michael Zwolak
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
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34
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Wege S, Gilliham M, Henderson SW. Chloride: not simply a 'cheap osmoticum', but a beneficial plant macronutrient. JOURNAL OF EXPERIMENTAL BOTANY 2017; 68:3057-3069. [PMID: 28379459 DOI: 10.1093/jxb/erx050] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
At macronutrient levels, chloride has positive effects on plant growth, which are distinct from its function in photosynthesis..
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Affiliation(s)
- Stefanie Wege
- Australian Research Council Centre of Excellence in Plant Energy Biology & The University of Adelaide, School of Agriculture, Food and Wine, Waite Research Precinct, PMB1, Glen Osmond, South Australia 5064, Australia
| | - Matthew Gilliham
- Australian Research Council Centre of Excellence in Plant Energy Biology & The University of Adelaide, School of Agriculture, Food and Wine, Waite Research Precinct, PMB1, Glen Osmond, South Australia 5064, Australia
| | - Sam W Henderson
- Australian Research Council Centre of Excellence in Plant Energy Biology & The University of Adelaide, School of Agriculture, Food and Wine, Waite Research Precinct, PMB1, Glen Osmond, South Australia 5064, Australia
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35
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Trick JL, Chelvaniththilan S, Klesse G, Aryal P, Wallace EJ, Tucker SJ, Sansom MSP. Functional Annotation of Ion Channel Structures by Molecular Simulation. Structure 2016; 24:2207-2216. [PMID: 27866853 PMCID: PMC5145807 DOI: 10.1016/j.str.2016.10.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 08/12/2016] [Accepted: 10/12/2016] [Indexed: 01/30/2023]
Abstract
Ion channels play key roles in cell membranes, and recent advances are yielding an increasing number of structures. However, their functional relevance is often unclear and better tools are required for their functional annotation. In sub-nanometer pores such as ion channels, hydrophobic gating has been shown to promote dewetting to produce a functionally closed (i.e., non-conductive) state. Using the serotonin receptor (5-HT3R) structure as an example, we demonstrate the use of molecular dynamics to aid the functional annotation of channel structures via simulation of the behavior of water within the pore. Three increasingly complex simulation analyses are described: water equilibrium densities; single-ion free-energy profiles; and computational electrophysiology. All three approaches correctly predict the 5-HT3R crystal structure to represent a functionally closed (i.e., non-conductive) state. We also illustrate the application of water equilibrium density simulations to annotate different conformational states of a glycine receptor.
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Affiliation(s)
- Jemma L Trick
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Sivapalan Chelvaniththilan
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK
| | - Gianni Klesse
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK
| | - Prafulla Aryal
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK; OXION Initiative in Ion Channels and Disease, University of Oxford, Oxford, UK
| | | | - Stephen J Tucker
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK; OXION Initiative in Ion Channels and Disease, University of Oxford, Oxford, UK
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK; OXION Initiative in Ion Channels and Disease, University of Oxford, Oxford, UK.
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Thomas M, Corry B. A computational assessment of the permeability and salt rejection of carbon nanotube membranes and their application to water desalination. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2015.0020. [PMID: 26712639 PMCID: PMC4696073 DOI: 10.1098/rsta.2015.0020] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Membranes made from nanomaterials such as nanotubes and graphene have been suggested to have a range of applications in water filtration and desalination, but determining their suitability for these purposes requires an accurate assessment of the properties of these novel materials. In this study, we use molecular dynamics simulations to determine the permeability and salt rejection capabilities for membranes incorporating carbon nanotubes (CNTs) at a range of pore sizes, pressures and concentrations. We include the influence of osmotic gradients and concentration build up and simulate at realistic pressures to improve the reliability of estimated membrane transport properties. We find that salt rejection is highly dependent on the applied hydrostatic pressure, meaning high rejection can be achieved with wider tubes than previously thought; while membrane permeability depends on salt concentration. The ideal size of the CNTs for desalination applications yielding high permeability and high salt rejection is found to be around 1.1 nm diameter. While there are limited energy gains to be achieved in using ultra-permeable CNT membranes in desalination by reverse osmosis, such membranes may allow for smaller plants to be built as is required when size or weight must be minimized. There are diminishing returns in further increasing membrane permeability, so efforts should focus on the fabrication of membranes containing narrow or functionalized CNTs that yield the desired rejection or selection properties rather than trying to optimize pore densities.
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Affiliation(s)
- Michael Thomas
- Department of Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, Australia Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia Life Sciences Computation Centre, Victorian Life Sciences Computation Initiative, Carlton, Victoria, Australia
| | - Ben Corry
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia
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Shen J, Schäfer AI. Factors affecting fluoride and natural organic matter (NOM) removal from natural waters in Tanzania by nanofiltration/reverse osmosis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 527-528:520-529. [PMID: 26005995 DOI: 10.1016/j.scitotenv.2015.04.037] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 04/11/2015] [Accepted: 04/11/2015] [Indexed: 06/04/2023]
Abstract
This study examined the feasibility of nanofiltration (NF) and reverse osmosis (RO) in treating challenging natural tropical waters containing high fluoride and natural organic matter (NOM). A total of 166 water samples were collected from 120 sources within northern Tanzania over a period of 16 months. Chemical analysis showed that 81% of the samples have fluoride levels exceeding the WHO drinking guideline of 1.5mg/L. The highest fluoride levels were detected in waters characterized by high ionic strength, high inorganic carbon and on some occasions high total organic carbon (TOC) concentrations. Bench-scale experiments with 22 representative waters (selected based on fluoride concentration, salinity, origin and in some instances organic matter) and 6 NF/RO membranes revealed that ionic strength and recovery affected fluoride retention and permeate flux. This is predominantly due to osmotic pressure and hence the variation of diffusion/convection contributes to fluoride transport. Different membranes had distinct fluoride removal capacities, showing different raw water concentration treatability limits regarding the WHO guideline compliance. BW30, BW30-LE and NF90 membranes had a feed concentration limit of 30-40 mg/L at 50% recovery. NOM retention was independent of water matrices but is governed predominantly by size exclusion. NOM was observed to have a positive impact on fluoride removal. Several mechanisms could contribute but further studies are required before a conclusion could be drawn. In summary, NF/RO membranes were proved to remove both fluoride and NOM reliably even from the most challenging Tanzanian waters, increasing the available drinking water sources.
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Affiliation(s)
- Junjie Shen
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom; The Nelson Mandela African Institute of Science and Technology, P.O. Box 447, Tengeru, Arusha, Tanzania
| | - Andrea I Schäfer
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
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Andoh Y, Yoshii N, Yamada A, Fujimoto K, Kojima H, Mizutani K, Nakagawa A, Nomoto A, Okazaki S. All-atom molecular dynamics calculation study of entire poliovirus empty capsids in solution. J Chem Phys 2014; 141:165101. [DOI: 10.1063/1.4897557] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- Y. Andoh
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - N. Yoshii
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - A. Yamada
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - K. Fujimoto
- Department of Pharmacy, College of Pharmaceutical Sciences, Ritsumeikan University, Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - H. Kojima
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - K. Mizutani
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
| | - A. Nakagawa
- Institute for Protein Research, Osaka University, Yamadaoka, Suita, Osaka 565-0871, Japan
| | - A. Nomoto
- Institute of Microbial Chemistry, Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan
| | - S. Okazaki
- Department of Applied Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
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Thomas M, Corry B, Hilder TA. What have we learnt about the mechanisms of rapid water transport, ion rejection and selectivity in nanopores from molecular simulation? SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:1453-1465. [PMID: 24851242 DOI: 10.1002/smll.201302968] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nanopores have demonstrated an extraordinary ability to allow water molecules to pass through their interiors at rates far exceeding expectations based on continuum theory. Moreover, simulation studies suggest that particular nanoscale pores have the potential to discriminate between water and salts as well as to distinguish between a range of different ion types. Some of the unusual features of transport in these nanopores have been elucidated with molecular dynamics simulation, specifically the spontaneous filling and rapid transport of water, the rejection of ions and the selection between ions. The main focus of this review, however, is the physical mechanisms which act to produce such remarkable behaviour at this scale, drawing on the many studies that have been conducted in the last decade. Since molecular dynamics simulations allow the motion of individual atoms to be followed over time, they have the potential to provide fundamental insight into the reasons why transport in nanoscale pores differs from expectations based on macroscopic theory. Gaining an understanding of the mechanisms of transport in these tiny pores should guide future experiments in this area aimed at developing novel technologies and improving existing membrane separation techniques.
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He Z, Corry B, Lu X, Zhou J. A mechanical nanogate based on a carbon nanotube for reversible control of ion conduction. NANOSCALE 2014; 6:3686-3694. [PMID: 24566473 DOI: 10.1039/c3nr06238d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Control of mass transport through nanochannels is of critical importance in many nanoscale devices and nanofiltration membranes. The gates in biological channels, which control the transport of substances across cell membranes, can provide inspiration for this purpose. Gates in many biological channels are formed by a constriction ringed with hydrophobic residues which can prevent ion conduction even when they are not completely physically occluded. In this work, we use molecular dynamics simulations to design a nanogate inspired by this hydrophobic gating mechanism. Deforming a carbon nanotube (12,12) with an external force can form a hydrophobic constriction in the centre of the tube that controls ion conduction. The simulation results show that increasing the magnitude of the applied force narrows the constriction and lowers the fluxes of K(+) and Cl(-) found under an electric field. With the exerted force larger than 5 nN, the constriction blocks the conduction of K(+) and Cl(-) due to partial dehydration while allowing for a noticeable water flux. Ion conduction can revert back to the unperturbed level upon force retraction, suggesting the reversibility of the nanogate. The force can be exerted by available experimental facilities, such as atomic force microscope (AFM) tips. It is found that partial dehydration in a continuous water-filled hydrophobic constriction is enough to close the channel, while full dewetting is not necessarily required. This mechanically deformed nanogate has many potential applications, such as a valve in nanofluidic systems to reversibly control ion conduction and a high-performance nanomachine for desalination and water treatment.
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Affiliation(s)
- Zhongjin He
- School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, Guangdong 510640, China.
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Richards LA, Richards BS, Corry B, Schäfer AI. Response to comment on "experimental energy barriers to anions transporting through nanofiltration membranes". ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:8987-8988. [PMID: 23808374 DOI: 10.1021/es402784j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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Richards LA, Richards BS, Corry B, Schäfer AI. Experimental energy barriers to anions transporting through nanofiltration membranes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:1968-1976. [PMID: 23298263 DOI: 10.1021/es303925r] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Environmentally relevant contaminants fluoride, chloride, nitrate, and nitrite face Arrhenius energy barriers during transport through nanofiltration (NF) membranes. The energy barriers were quantified using crossflow filtration experiments and were in the range of 7-17 kcal·mol(-1), according to ion type and membrane type (Filmtec NF90 and NF270). Fluoride faced a comparatively high energy barrier for both membranes. This can be explained by the strong hydration energy of fluoride rather than other ion properties such as bare ion radius, fully hydrated radius, Stokes radius, diffusion coefficient, or ion charge. The energy barrier for fluoride decreased with pressure, indicating an impact of directional force on energy barriers. The influence of temperature-induced pore radius variability and viscosity on energy barriers was considered. The novel link between energy barriers and ion properties emphasizes the importance of ion hydration and/or partial dehydration mechanisms in determining transport in NF.
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Affiliation(s)
- Laura A Richards
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
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