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Jiang H, Deng K, Wang Y, Sun C. Investigation of ion association kinetics in Na 2SO 4-H 2O by excess Raman spectroscopy and 2D correlation Raman spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 322:124673. [PMID: 38981288 DOI: 10.1016/j.saa.2024.124673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 06/12/2024] [Accepted: 06/17/2024] [Indexed: 07/11/2024]
Abstract
The ion association of salts aqueous solutions have long captivated the attention of researchers within the field of physical chemistry. In this paper, we have performed a comprehensive analysis of ion interactions in sodium sulfate (Na2SO4) aqueous solutions using a combination of high-resolution techniques, including excess (ERS) and two-dimensional correlation (2DCRS) Raman spectroscopy in conjunction with molecular dynamics (MD) calculations. The Raman spectrum shows that two inflection points in the Raman shift of the O-H vibration are observed with the increase in Na2SO4 concentration. Simultaneously, a new peak of the SO42- vibration appears at first inflection point, representing the formation of ion association. Further analysis based on ERS and 2CRS reveals that these two inflection points correspond respectively to the formation of ion pairs (CIPs) and small ion clusters. Importantly, MD simulations confirm the above experimental results. Our study provides evidence for ion association and clustering in aqueous in salt ion aqueous solutions.
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Affiliation(s)
- Huan Jiang
- Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China; Jilin Police College, Changchun 130117, China
| | - Ke Deng
- Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China
| | - Yubo Wang
- Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China
| | - Chenglin Sun
- Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China.
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2
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Xu Y, Guo Y. New Local Composition Model for Correlating of the Molar Conductivity of Ionic Liquid-Solvent Systems over the Whole Concentration Range. J Phys Chem B 2024; 128:2181-2189. [PMID: 38407026 DOI: 10.1021/acs.jpcb.3c07173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Considering that traditional electrolyte models are limited to use in the solvent-rich region, the development of new models to describe the molar conductivity (Λm) over the whole concentration range of ionic liquid (IL)-solvent systems is a meaningful study. Based on the idea of local composition and the law of independent ion migration, a new model is proposed in this study and used to successfully correlate the relationship between Λm and composition over the whole concentration range for 18 IL-solvent systems with satisfactory fitting accuracy. Meanwhile, the electrical conductivity (κ) of the systems is estimated using the calculated Λm. Moreover, the strength of anion-cation, anion-solvent, and cation-solvent interactions in the systems is explored by the obtained energy parameters, and the effect of the solvent on the interactions is investigated. The proposed model provides a new method to accurately describe the conductivity property of IL-solvent systems over the whole concentration range.
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Affiliation(s)
- Yingjie Xu
- Department of Chemistry, Shaoxing University, Shaoxing 312000, China
| | - Yujun Guo
- Department of Chemistry, Shaoxing University, Shaoxing 312000, China
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3
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Zhao R, Xu X, Wang Z, Zheng Y, Zhou Y. The structural and hydrogen bonding properties of ionic liquid-co-solvent binary mixtures: the distinct behaviors of two anions. Phys Chem Chem Phys 2023; 25:24355-24363. [PMID: 37672223 DOI: 10.1039/d3cp02430j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Abstract
In practical applications, ionic liquids are often mixed with co-solvents. Understanding their structures and the interactions between them is a prerequisite for expanding their range of applications. In this work, spectroscopic and theoretical methods were employed to explore the structure and hydrogen bonding behaviors of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIMTFSI)/1-ethyl-3-methylimidazolium thiocyanate (EMIMSCN) and co-solvents. It can be concluded that the hydrogen bonds associated with C2-H and C4,5-H are enhanced with the addition of co-solvents in the EMIMTFSI-DMSO system, while those associated with C4,5-H are weakened in the EMIMSCN-DMSO system. Infrared and excess spectra in the v(imidazolium C-H) range of EMIMSCN-CD3CN/CD3COCD3 systems further indicate that the abnormal change of hydrogen bonds associated with C4,5-H can be attributed to [SCN]-. These differences can be explained by the change of the primary interaction site. For EMIMTFSI, the primary interaction site in ion pairs and ion clusters is always C2-H, while for EMIMSCN, the primary interaction site in ion pairs is C2-H, and in ion clusters, it becomes C4,5-H. In the EMIMTFSI-DMSO system, the co-solvent primarily interacts with C4,5-H, while in the EMIMSCN-DMSO/CH3CN/CH3COCH3 systems, it primarily interacts with C2-H. In addition, several complexes are identified through excess infrared spectra and DFT calculations.
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Affiliation(s)
- Rui Zhao
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
| | - Xianzhen Xu
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
| | - Zonghua Wang
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
| | - Yanzhen Zheng
- College of Ocean Food and Biological Engineering, Jimei University, Xiamen 361021, P. R. China.
| | - Yu Zhou
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China.
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Dudariev D, Koverga V, Kalugin O, Miannay FA, Polok K, Takamuku T, Jedlovszky P, Idrissi A. Insight to the Local Structure of Mixtures of Imidazolium-Based Ionic Liquids and Molecular Solvents from Molecular Dynamics Simulations and Voronoi Analysis. J Phys Chem B 2023; 127:2534-2545. [PMID: 36892904 DOI: 10.1021/acs.jpcb.2c08818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/10/2023]
Abstract
While the physicochemical properties as well as the NMR and vibration spectroscopic data of the mixtures of ionic liquids (ILs) with molecular solvents undergo a drastic change around the IL mole fraction of 0.2, the local structure of the mixtures pertaining to this behavior remains unclear. In this work, the local structure of 12 mixtures of 1-butyl-3-methylimidazolium cation (C4mim+) combined with perfluorinated anions, such as tetrafluoroborate (BF4-), hexafluorophosphate (PF6-), trifluoromethylsulfonate (TFO-), and bis(trifluoromethanesulfonyl)imide, (TFSI-), and aprotic dipolar solvents, such as acetonitrile (AN), propylene carbonate (PC), and gamma butyrolactone (γ-BL) is studied by molecular dynamics simulations in the entire composition range, with an emphasis on the IL mole fractions around 0.2. Distributions of metric properties corresponding to the Voronoi polyhedra of the particles (volume assigned to the particles, local density, radius of spherical voids) are determined, using representative sites of the cations, anions, and the solvent molecules, to characterize the changes in the local structure of these mixtures. By analyzing the mole fraction dependence of the average value, fluctuation, and skewness parameter of these distributions, the present study reveals that, around the IL mole fraction of 0.2, the local structure of the mixture undergoes a transition between that determined by the interionic interactions and that determined by the interactions between the ions and solvent molecules. It should be noted that the strength of the interactions between the ions and the solvent molecules, modulated by the change in the composition of the mixture, plays an important role in the occurrence of this transition. The signature of the change in the local structure is traced back to the nonlinear change of the mean values, fluctuations, and skewness values of the metric Voronoi polyhedra distributions.
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Affiliation(s)
- Dmytro Dudariev
- University of Lille, CNRS UMR 8516 -LASIRe - Laboratoire Avancé de Spectroscopie pour les Interactions la Réactivité et l'environnement, 59000 Lille, France
- Department of Inorganic Chemistry, V.N. Karazin Kharkiv National University, Svobody sq. 4, 61022 Kharkiv, Ukraine
| | - Volodymyr Koverga
- Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607, United States
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Oleg Kalugin
- Department of Inorganic Chemistry, V.N. Karazin Kharkiv National University, Svobody sq. 4, 61022 Kharkiv, Ukraine
| | - François-Alexandre Miannay
- University of Lille, CNRS UMR 8516 -LASIRe - Laboratoire Avancé de Spectroscopie pour les Interactions la Réactivité et l'environnement, 59000 Lille, France
| | - Kamil Polok
- Faculty of Chemistry, Laboratory of Spectroscopy and Intermolecular Interactions, University of Warsaw, Żwirki i Wigury 101, Warsaw 02-089, Poland
| | - Toshiyuki Takamuku
- Department of Chemistry and Applied Chemistry, Faculty of Science and Engineering, Saga University, Honjo-machi, Saga 840-8502, Japan
| | - Pál Jedlovszky
- Department of Chemistry, Eszterházy Károly University, Leányka u. 6, 3300 Eger, Hungary
| | - Abdenacer Idrissi
- University of Lille, CNRS UMR 8516 -LASIRe - Laboratoire Avancé de Spectroscopie pour les Interactions la Réactivité et l'environnement, 59000 Lille, France
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5
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Zhao R, Xu X, Zhou Y, Wang Z, Zhou Y. Study on the structural characteristics and interaction mechanisms of ionic liquid mixtures with a common imidazolium cation. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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6
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Kaneko K, Yoshimura Y, Shimizu A. Experimental and computational studies on the ion dissociation states of 1-butyl-3-methyimidazolium tetrafluoroborate in water and alcohols. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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7
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Iqbal Hossain M, Blanchard G. Dilution-induced changes in room temperature ionic liquids. Persistent compositional heterogeneity and the importance of dipolar interactions. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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8
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Tang H, Cai J, Zhu CY, Chen GJ, Wang XH, Sun CY. Review on the clustering behavior in aqueous solutions. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Structure and hydrogen-bond properties of N-alkyl-N-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide and ethanol: A combination of FTIR and theoretical studies. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133488] [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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10
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Microstructures of Hydrophobic Ionic Liquids via Tuning Water Networks: Theoretical and Experimental Investigations. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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11
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Hydrogen bonding between 1-ethyl-3-methyl-imidazolium dicyanamide ionic liquid and selected co-solvents with varying polarity: A DFT study. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Chen J, Zeng X, Chen L. Evolution of microstructures and hydrogen bond interactions within choline amino acid ionic liquid and water mixtures. Phys Chem Chem Phys 2022; 24:17792-17808. [PMID: 35848866 DOI: 10.1039/d2cp01990f] [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
The microstructures and interactions of choline amino acid ([Cho][AA]) ionic liquid (IL) and water molecules were investigated. When water was added to [Cho][AA], the asymmetric and symmetric vibration peaks of the -COO- group shifted to lower and higher wavenumbers, respectively. The increase of water addition also resulted in increased conductivity values and decreased viscosity values of [Cho][AA]-water mixtures. These features are consistent with the physical picture that [Cho][AA] could gradually dissociate into hydrated tight ion pairs and water-separated ion pairs and then into free and solvated ions. When it comes to different anions (choline lysine, [Cho][Lys], and choline aspartic acid, [Cho][Asp]), the anion structure has a significant regulation on [Cho][AA]-water interactions. The shorter side chain length and strong polar -COOH group of Asp- endow [Cho][Asp] with stronger cation-anion interactions and less dissociation by water molecules. As a result, the frequency shift degrees and conductivity values of [Cho][Asp]-water mixtures were lower, and the viscosity values were higher than those of [Cho][Lys]-water mixtures. And, [Cho][Lys] could completely dissociate as free hydrated ions at w : IL ≥ 7 : 3, while the free hydrated ions of [Cho][Asp] only occurred when the w : IL ratio reached 8 : 2. These results can ease the experimental effort and improve the application efficiency of [Cho][AA] ILs.
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Affiliation(s)
- Jin Chen
- Ministry of Education Engineering Research Center of Starch & Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Xixi Zeng
- Ministry of Education Engineering Research Center of Starch & Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Ling Chen
- Ministry of Education Engineering Research Center of Starch & Protein Processing, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
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13
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Biswas A, Mallik BS. Microheterogeneity-Induced Vibrational Spectral Dynamics of Aqueous 1-Alkyl-3-methylimidazolium Tetrafluoroborate Ionic Liquids of Different Cationic Chain Lengths. J Phys Chem B 2022; 126:5523-5533. [PMID: 35833870 DOI: 10.1021/acs.jpcb.2c03561] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have monitored the impacts of an increment in the alkyl chain length of the imidazolium-based tetrafluoroborate ionic liquids on the local deuteroxyl probe modes of interest. For this study, we have taken 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIm][BF4], 1-butyl-3-methylimidazolium tetrafluoroborate [BMIm][BF4], 1-octyl-3-methylimidazolium tetrafluoroborate [OMIm][BF4], and 1-decyl-3-methylimidazolium tetrafluoroborate [DMIm][BF4] ionic liquid solutions with 5% HOD in H2O as the vibrational reporter of the associated ultrafast system dynamics. Classical molecular dynamics (MD) simulations were employed to determine molecular structure and dynamic properties, while the spectral profiles were derived by applying the wavelet analysis of classical trajectories. Spatial distribution functions reveal the heterogeneity within the molecular structures of the ionic liquids (ILs) with varying alkyl chain lengths. The intense position of the spectral peak, the frequency corresponding to the shoulder peak, and the spectral linewidth of the O-D stretch distribution are not influenced by the increment in the cationic chain length. In addition, the ionic liquid (IL) [BMIm][BF4] exhibits a notable trend; the dynamic timescales are longer than the other studied systems. Therefore, we have performed the Voronoi decomposition analysis of the ionic and the polar-apolar domains, symmetrically increasing the length of alkyl chains on the IL cations. Domain analysis reveals structural microheterogeneity; the anions form discrete domains, and the ionic liquid constituting cations form continuous domains irrespective of the alkyl chain length on the imidazolium cations. Therefore, this computational ultrafast spectroscopy study aids in forming a molecular-level picture of the ionic liquid cations and anions in the liquid phase, providing a detailed interpretation of the spectral properties of the probe stretching vibrations.
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Affiliation(s)
- Aritri Biswas
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
| | - Bhabani S Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
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14
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Han Q, Brown SJ, Drummond CJ, Greaves TL. Protein aggregation and crystallization with ionic liquids: Insights into the influence of solvent properties. J Colloid Interface Sci 2022; 608:1173-1190. [PMID: 34735853 DOI: 10.1016/j.jcis.2021.10.087] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022]
Abstract
Ionic liquids (ILs) have been used in solvents for proteins in many applications, including biotechnology, pharmaceutics, and medicine due to their tunable physicochemical and biological properties. Protein aggregation is often undesirable, and predominantly occurs during bioprocesses, while the aggregation process can be reversible or irreversible and the aggregates formed can be native/non-native and soluble/insoluble. Recent studies have clearly identified key properties of ILs and IL-water mixtures related to protein performance, suggesting the use of the tailorable properties of ILs to inhibit protein aggregation, to promote protein crystallization, and to control protein aggregation pathways. This review discusses the critical properties of IL and IL-water mixtures and presents the latest understanding of the protein aggregation pathways and the development of IL systems that affect or control the protein aggregation process. Through this feature article, we hope to inspire further advances in understanding and new approaches to controlling protein behavior to optimize bioprocesses.
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Affiliation(s)
- Qi Han
- School of Science, STEM College, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - Stuart J Brown
- School of Science, STEM College, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - Calum J Drummond
- School of Science, STEM College, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia
| | - Tamar L Greaves
- School of Science, STEM College, RMIT University, 124 La Trobe Street, Melbourne, VIC 3000, Australia.
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15
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Bioucas FEB, Queirós CSGP, Lozano-Martín D, Ferreira MS, Paredes X, Santos ÂF, Santos FJV, Lopes MLM, Lampreia IMS, Lourenço MJV, de Castro CAN, Massonne K. [C2mim][CH3SO3]─A Suitable New Heat Transfer Fluid? Part 2: Thermophysical Properties of Its Mixtures with Water. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.1c02970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Francisco E. B. Bioucas
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Carla S. G. P. Queirós
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Daniel Lozano-Martín
- Grupo de Termodinámica y Calibración (TERMOCAL), Research Institute on Bioeconomy, Escuela de Ingenierías Industriales, Universidad de Valladolid, Paseo del Cauce, 59, E-47011 Valladolid, Spain
| | - M. S. Ferreira
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Xavier Paredes
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Ângela F. Santos
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Fernando J. V. Santos
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Manuel L. M. Lopes
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Isabel M. S. Lampreia
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Maria José V. Lourenço
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Carlos A. Nieto de Castro
- Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
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16
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Ivanov MY, Surovtsev NV, Fedin MV. Ionic liquid glasses: properties and applications. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Chen J, Zeng X, Chen L. Regulation nature of water-choline amino acid ionic liquid mixtures on the disaggregation behavior of starch. Carbohydr Polym 2021; 272:118474. [PMID: 34420733 DOI: 10.1016/j.carbpol.2021.118474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 07/03/2021] [Accepted: 07/19/2021] [Indexed: 10/20/2022]
Abstract
Fully green and renewable choline amino acid (choline glycine, [Cho][Gly]) ionic liquid (IL) was firstly explored and evaluated as a solvent for starch. By a thorough investigation of microstructure evolution of water-[Cho][Gly] (w:IL) mixtures, its regulation mechanism on disaggregation behaviors of starch was revealed and illuminated. Compared with pure water, existed hydrated free ions in w:IL-9:1 and w:IL-7:3 restrict starch-water interactions to disaggregate of starch, thus hampering gelatinization of starch. While the gelatinization temperatures decreased at w:IL-5:5 and w:IL-4:6 mixtures with a result of homogeneous starch solutions. The tight and water-separated ion pairs existed at w:IL-5:5 and w:IL-4:6 mixtures allow adequate ions to interact with starch to facilitate the disaggregation of starch. At w:IL-2:8 and w:IL-0:10 mixtures, an exothermic dissolution of starch was observed at high temperatures as a result of predominant starch-ion interactions. These results provide the possibility of using [Cho][Gly] solvent to meet various application requirements of starch.
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Affiliation(s)
- Jin Chen
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Vegetable Protein Processing Ministry of Education, South China University of Technology, Guangzhou 510640, China
| | - Xixi Zeng
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Vegetable Protein Processing Ministry of Education, South China University of Technology, Guangzhou 510640, China
| | - Ling Chen
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Vegetable Protein Processing Ministry of Education, South China University of Technology, Guangzhou 510640, China.
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18
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Peek Inside the Water Mixtures of Ionic Liquids at Molecular Level: Microscopic Properties Probed by EPR Spectroscopy. Int J Mol Sci 2021; 22:ijms222111900. [PMID: 34769336 PMCID: PMC8584414 DOI: 10.3390/ijms222111900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 01/06/2023] Open
Abstract
Many ionic liquids (ILs) can be mixed with water, forming either true solutions or emulsions. This favors their applications in many respects, but at the same time might strongly alter their physicochemical properties. A number of methods exist for studying the macroscopic properties of such mixtures, whereas understanding their characteristics at micro/nanoscale is rather challenging. In this work we investigate microscopic properties, such as viscosity and local structuring, in binary water mixtures of IL [Bmim]BF4 in liquid and glassy states. For this sake, we use continuous wave and pulse electron paramagnetic resonance (EPR) spectroscopy with dedicated spin probes, located preferably in IL-rich domains or distributed in IL- and water-rich domains. We demonstrate that the glassy-state nanostructuring of IL-rich domains is very similar to that in neat ILs. At the same time, in liquid state the residual water makes local viscosity in IL-rich domains noticeably different compared to neat ILs, even though the overwhelming amount of water is contained in water-rich domains. These results have to be taken into account in various applications of IL-water mixtures, especially in those cases demanding the combinations of optimum micro- and macroscopic characteristics.
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19
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Zhang S, Wang Y, Yao J, Li H. Special Mixing Behavior of Chelate-based Ionic Liquid with Methanol. Chemphyschem 2021; 22:2050-2057. [PMID: 34327806 DOI: 10.1002/cphc.202100422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/28/2021] [Indexed: 11/10/2022]
Abstract
Compared to the general ionic liquids (ILs), a significant deviation of the binary mixtures of 1-decyl-3-methylimidazolium tri(hexafluoroacetylaceto)-copper(II) ([C10 mim][Cu(hfacac)3 ]) with methanol was found, indicating the way methanol interacts with ILs might be governed by the special structure of the chelating anion. IR results showed that the v (C2-H) of 1-decyl-3-methylimidazolium hexafluoroacetylacetonate ([C10 mim][hfacac]) blue-shifted more significantly than that of [C10 mim][Cu(hfacac)3 ], meanwhile the v (C=O) red-shifted in [C10 mim][Cu(hfacac)3 ], which is contrast with that in [C10 mim][hfacac]. Two-dimensional correlation analysis of the FTIR spectra indicated that the chelating cavity has little effect on the sequence of the ILs sites that interact with methanol. Combined with small angle X-ray scattering (SAXS) results, the picture of mixing processes in these two systems were proposed. Methanol interacts directly with the anion followed by the cation in [C10 mim][hfacac], while methanol preferentially enters the chelating cavity and enhances the packing effect in the [C10 mim][Cu(hfacac)3 ] system.
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Affiliation(s)
- Songna Zhang
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou, 310027, China
| | - Yongtao Wang
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou, 310027, China
| | - Jia Yao
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou, 310027, China
| | - Haoran Li
- Department of Chemistry, ZJU-NHU United R&D Center, Zhejiang University, Hangzhou, 310027, China.,State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China
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Zebarjad FS, Wang Z, Li H, Hu S, Tang Y, Tsotsis TT. Investigation of CO2 and methanol solubility at high pressure and temperature in the ionic liquid [EMIM][BF4] employed during methanol synthesis in a membrane-contactor reactor. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2021.116722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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21
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Zheng YZ, Chen H, Zhou Y, Zhang YC. Combination of FTIR and DFT to study the structure and hydrogen-bond properties of alkylammonium-based ILs and DMSO mixtures. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115940] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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22
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Maciejewska M, Sowińska A. Influence of Fillers and Ionic Liquids on the Crosslinking and Performance of Natural Rubber Biocomposites. Polymers (Basel) 2021; 13:polym13101656. [PMID: 34069680 PMCID: PMC8160702 DOI: 10.3390/polym13101656] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 12/15/2022] Open
Abstract
This work concerns the effect of fillers and ionic liquids on the cure characteristics of natural rubber (NR) compounds, as well as the mechanical and thermal properties of the vulcanizates. Three types of white filler were applied, such as cellulose, nanosized silica and hydrotalcite, to modify the performance of NR composites. Additionally, ionic liquids (ILs) with bromide anion and different cations, i.e., 1-butyl-3-methylimidazolium (Bmi) and 1-butyl-3-methylpyrrolidinium (Bmpyr), were used to improve the cure characteristics of NR compounds and functional properties of the vulcanizates. The type of filler and the structure of ILs were proved to affect the rheometric properties and cure characteristics of NR compounds as well as the performance of the NR vulcanizates. Owing to the adsorption of curatives onto the surface, silica reduced the activity of the crosslinking system, prolonging the optimal vulcanization time of NR compounds and reducing the crosslinking degree of the elastomer. However, silica-filled NR exhibited the highest thermal stability. Hydrotalcite increased the crosslink density and, consequently, the mechanical properties of the vulcanizates, but deteriorated their thermal stability. ILs beneficially influenced the cure characteristics of NR compounds, as well as the crosslink density and mechanical performance of the vulcanizates, particularly those filled with silica. Cellulose did not significantly affect the vulcanization of NR compounds and crosslink density of the vulcanizates compared to the unfilled elastomer, but deteriorated their tensile strength. On the other hand, cellulose improved the thermal stability and did not considerably alter the damping properties of the vulcanizates.
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Frizzo CP, Vieira JCB, Krüger N, Paz AV, Zanatta N, Villetti MA. Heating Profile of Long Alkyl Chain Ionic Liquid Doped Solvents Under Ultrasound Irradiation. J SOLUTION CHEM 2021. [DOI: 10.1007/s10953-021-01054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Zheng YZ, Zhou Y, Deng G, Guo R, Chen DF. Structures and non-covalent interaction behaviours of binary systems containing the ionic liquid 1-(2'-hydroxylethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and chloroform. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 244:118843. [PMID: 32896709 DOI: 10.1016/j.saa.2020.118843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/17/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
Mixtures of ionic liquids (ILs) and molecular solvents can overcome the drawbacks (high viscosity, high polarity, and high cost) of pure ILs and extend their practical use. The structural and interaction properties of ILs form the bases for understanding their properties. In this work, the structural properties of the mixtures of an IL, 1-(2'-hydroxylethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2OHMIM][Tf2N]), with chloroform, a molecular solvent of weak polarity, in various concentrations were analysed using Fourier transform infrared spectroscopy and density functional theory calculations. Excess spectra were used to analyse the infrared spectra. The IL forms a stable ion cluster-CDCl3 complex with CDCl3 in the concentration range investigated. In the ion cluster-CDCl3 complex, the hydrogen atom of CDCl3 forms hydrogen-bonds with the fluorine atoms of the anion. In addition, the chlorine atom of CDCl3 forms a halogen-bond with the oxygen atom of the anion. All the hydrogen and halogen-bonds identified between the [C2OHMIM][Tf2N] ion cluster and CDCl3 exhibit low strength, closed shells, and electrostatically dominant interactions.
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Affiliation(s)
- Yan-Zhen Zheng
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yu Zhou
- School of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, PR China
| | - Geng Deng
- Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, PR China
| | - Rui Guo
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Da-Fu Chen
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
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25
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Zheng YZ, Zhou Y, He HY, Guo R, Chen DF. Nitrile group as IR probe to detect the structure and hydrogen-bond properties of piperidinium/pyrrolidinium based ionic liquids and acetonitrile mixtures. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.114548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Kalhor P, Zheng YZ, Ashraf H, Cao B, Yu ZW. Influence of Hydration on the Structure and Interactions of Ethaline Deep-Eutectic Solvent: A Spectroscopic and Computational Study. Chemphyschem 2020; 21:995-1005. [PMID: 32232896 DOI: 10.1002/cphc.202000165] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/29/2020] [Indexed: 01/31/2023]
Abstract
Deep-eutectic solvents (DESs) are regarded as alternative green solvents to ionic liquids. In this work we report the structural properties and hydrogen bonding (H-bonding) interactions of an aqueous DES system. The used DES, ethaline (ETH), is composed of choline chloride and ethylene glycol (EG) in 1 : 2 molar ratio. The investigations were carried out by FTIR spectroscopy combined with quantum chemical calculations. Excess spectroscopy and two-dimensional correlation spectroscopy (2D-COS) were used to explore the data in detail. The results showed that, upon mixing, ETH transforms to EG dimers and trimers and D2 O clusters transform to various ETH-D2 O complexes. Theoretical calculations show that water molecules insert between the anion and cation of ETH, break the strong doubly ionic Cl-… H-OCh+ H-bond, share charges of the ions and form H-bond with them, thus modulate the interaction properties of ETH. This study deepens our molecular-level understanding of the system and would shed light on its applications.
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Affiliation(s)
- Payam Kalhor
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yan-Zhen Zheng
- College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, China
| | - Hamad Ashraf
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Bobo Cao
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Zhi-Wu Yu
- MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, China
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Shyama M, Lakshmipathi S. Water confined (H2O) n=1–10 amino acid-based ionic liquids – A DFT study on the bonding, energetics and IR spectra. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112720] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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28
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A detail study of the microstructure of methyl benzoate/methanol mixture proved by IR spectra, excess infrared wavenumber, and physicochemical properties. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.112521] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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29
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Zheng YZ, Zhou Y, Deng G, Guo R, Chen DF. A combination of FTIR and DFT to study the microscopic structure and hydrogen-bonding interaction properties of the [BMIM][BF 4] and water. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 226:117624. [PMID: 31605965 DOI: 10.1016/j.saa.2019.117624] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 07/08/2019] [Accepted: 10/06/2019] [Indexed: 06/10/2023]
Abstract
The structure and hydrogen-bond interaction property of water and a model ionic liquid (IL): 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) were studied using the combination of Fourier transform infrared spectroscopy (FTIR) and density functional theory (DFT) calculations. The O‒D stretching vibration region of the deuterated water was an area of special focus. Excess infrared spectroscopy with enhanced resolution was applied to analyse the original infrared spectra of v(O‒D). It is found that: (1) [BMIM][BF4] forms stable hydrogen-bonds with water in the mixture. (2) The hydrogen-bonds are weak strength, closed shell and electrostatic dominant interactions. The preferred interaction site of [BMIM]+ cation is the hydrogen atom at the C2. (3) Cage hexamer water, cyclic tetramer water, cyclic trimer water, ion cluster-water complex, ion pair-water, and anion-water complexes are identified in the mixture. When the mole fraction of D2O (x(D2O)) is larger than 0.9, ion cluster and ion pair were broken apart into individual cations and anions. The cage hexamer water, cyclic tetramer water, and cyclic trimer water disappear at x(D2O) < 0.8, 0.5, and 0.3, respectively. HDO formed by H/D isotope exchange was detected when x(D2O) is less than 0.3.
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Affiliation(s)
- Yan-Zhen Zheng
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, PR China; Department of Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yu Zhou
- School of Chemistry and Chemical Engineering, Qingdao University, Qingdao, 266071, PR China
| | - Geng Deng
- Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, PR China
| | - Rui Guo
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, PR China
| | - Da-Fu Chen
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, PR China.
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Verma A, Stoppelman JP, McDaniel JG. Tuning Water Networks via Ionic Liquid/Water Mixtures. Int J Mol Sci 2020; 21:E403. [PMID: 31936347 PMCID: PMC7013630 DOI: 10.3390/ijms21020403] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 12/19/2019] [Accepted: 01/03/2020] [Indexed: 11/17/2022] Open
Abstract
Water in nanoconfinement is ubiquitous in biological systems and membrane materials, with altered properties that significantly influence the surrounding system. In this work, we show how ionic liquid (IL)/water mixtures can be tuned to create water environments that resemble nanoconfined systems. We utilize molecular dynamics simulations employing ab initio force fields to extensively characterize the water structure within five different IL/water mixtures: [BMIM + ][BF 4 - ], [BMIM + ][PF 6 - ], [BMIM + ][OTf - ], [BMIM + ][NO 3 - ]and [BMIM + ][TFSI - ] ILs at varying water fraction. We characterize water clustering, hydrogen bonding, water orientation, pairwise correlation functions and percolation networks as a function of water content and IL type. The nature of the water nanostructure is significantly tuned by changing the hydrophobicity of the IL and sensitively depends on water content. In hydrophobic ILs such as [BMIM + ][PF 6 - ], significant water clustering leads to dynamic formation of water pockets that can appear similar to those formed within reverse micelles. Furthermore, rotational relaxation times of water molecules in supersaturated hydrophobic IL/water mixtures indicate the close-connection with nanoconfined systems, as they are quantitatively similar to water relaxation in previously characterized lyotropic liquid crystals. We expect that this physical insight will lead to better design principles for incorporation of ILs into membrane materials to tune water nanostructure.
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Affiliation(s)
| | | | - Jesse G. McDaniel
- Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta 30332-0400, Georgia; (A.V.); (J.P.S.)
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31
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Queirós C, Paredes X, Avelino T, Bastos D, Ferreira M, Santos F, Santos A, Lopes M, Lourenço M, Pereira H, Nieto de Castro C. The influence of water on the thermophysical properties of 1-ethyl-3-methylimidazolium acetate. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2019.111925] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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32
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Zheng YZ, Chen H, Zhou Y, Geng D, He HY, Wu LM. The structure and hydrogen-bond properties of N-alkyl- N-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide and DMSO mixtures. Phys Chem Chem Phys 2020; 22:28021-28031. [PMID: 33305305 DOI: 10.1039/d0cp03640d] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mixing ionic liquids (ILs) with molecular solvents can extend the practical applications of ILs and overcome the drawbacks of neat ILs. Knowledge on the structure and hydrogen-bond interaction properties of IL-molecular solvent mixtures is essential for chemical applications. In this work, the structure and hydrogen-bond features of N-alkyl-N-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide ([CnMPyr][Tf2N], n = 3, 4, 6 and 8) and DMSO mixtures were studied using Fourier transform infrared spectroscopy (FTIR) and density functional theory (DFT) calculations. Excess infrared absorption spectroscopy and two-dimensional correlation spectroscopy (2D-COS) were employed to extract structural information on the mixtures from the C-D systematic stretching vibrational (νs(C-D)) region of the methyl groups in DMSO-d6. It was found that the mixing process of [CnMPyr][Tf2N] and DMSO is non-ideal and interaction complexes form between [CnMPyr][Tf2N] and DMSO-d6. They are ion cluster-DMSO-d6 complexes and ion pair-DMSO-d6 complexes. In the mixing processes, the species present in pure DMSO gradually decrease from DMSO dimer to DMSO monomer with an increase in ILs. Besides, the ion cluster-DMSO complexes gradually increase, while the ion pair-DMSO complexes decrease due to the strong electrostatic interaction between the cation and anion. In the ion cluster-DMSO complexes and ion pair-DMSO complexes, the ring hydrogen atoms of the methylene group directly attached to the nitrogen atom are the preferred interaction sites of the [CnMPyr]+ cations. All the hydrogen bonds in the identified complexes are closed-shell, electrostatically dominant and weak.
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Affiliation(s)
- Yan-Zhen Zheng
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, P. R. China
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He Y, Saang’onyo D, Ladipo F, Knutson BL, Rankin SE. In Situ Fourier Transform Infrared Study of the Effects of Silica Mesopore Confinement on Hydration of Ionic Liquid 1-Butyl-3-methylimidazolium Chloride. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b03314] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zheng YZ, Zhou Y, Deng G, Guo R, Chen DF. The structure and hydrogen-bond behaviours of binary systems containing ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate and methanol/ethanol. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 223:117312. [PMID: 31255860 DOI: 10.1016/j.saa.2019.117312] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 06/18/2019] [Accepted: 06/23/2019] [Indexed: 06/09/2023]
Abstract
Mixing ionic liquids (ILs) with a molecular cosolvent can largely reduce the high viscosities, high polarities, and high costs of ILs. The macroscopic properties of IL-cosolvent mixtures have been studied extensively. However, some fundamental questions regarding the microscopic properties of the binary mixtures still remain to be answered. In this work, the structural and hydrogen-bond features of binary systems containing 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) and methanol/ethanol were studied by using the combination of Fourier-transform infrared spectroscopy (FTIR) and density functional theory (DFT) calculations. Excess infrared absorption spectroscopy with enhanced spectral resolution was used to analyse the original IR spectra. The alcohol tetramer/larger multimers, alcohol trimer, anion-alcohol, ion pair-alcohol, and ion cluster-alcohol complexes were identified in the excess spectra. With the increasing [BMIM][BF4], the alcohol multimers gradually broke out from the larger multimers into smaller multimers. The hydrogen-bonded complex related with anion [BF4]- and alcohol gradually changes from anion-alcohol complex to ion pair-alcohol complex. The ion cluster-alcohol appears when the x(alcohol) is <0.50. The most stable optimized geometries of anion-alcohol, ion pair-alcohol, and ion cluster-alcohol were carefully analysed, and the hydrogen-bonds were identified. All of the hydrogen-bonds in these studied complexes had weak strength, closed shells and electrostatically dominant interactions.
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Affiliation(s)
- Yan-Zhen Zheng
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yu Zhou
- School of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, PR China
| | - Geng Deng
- Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, PR China
| | - Rui Guo
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Da-Fu Chen
- College of Bee Science, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
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Figueiredo NM, Voroshylova IV, Koverga VA, Ferreira ES, Cordeiro MND. Influence of alcohols on the inter-ion interactions in ionic liquids: A molecular dynamics study. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111538] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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36
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Ivanov MY, Prikhod’ko SA, Adonin NY, Fedin MV. Structural Anomalies in Binary Mixtures of Ionic Liquid [Bmim]BF4 with Water Studied by EPR. J Phys Chem B 2019; 123:9956-9962. [DOI: 10.1021/acs.jpcb.9b08933] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Mikhail Yu. Ivanov
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia
- Novosibirsk State University, Pirogova Street 2, 630090 Novosibirsk, Russia
| | - Sergey A. Prikhod’ko
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Avenue 5, 630090 Novosibirsk, Russia
| | - Nicolay Yu. Adonin
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Avenue 5, 630090 Novosibirsk, Russia
| | - Matvey V. Fedin
- International Tomography Center SB RAS, Institutskaya Street 3a, 630090 Novosibirsk, Russia
- Novosibirsk State University, Pirogova Street 2, 630090 Novosibirsk, Russia
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37
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Kundu K, Chandra GK, Umapathy S, Kiefer J. Spectroscopic and computational insights into the ion-solvent interactions in hydrated aprotic and protic ionic liquids. Phys Chem Chem Phys 2019; 21:20791-20804. [PMID: 31513201 DOI: 10.1039/c9cp03670a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ionic liquids (ILs) and their aqueous solutions are emerging media for solving and manipulating biochemical molecules such as proteins. Unleashing the full potential however requires a detailed mechanistic understanding of how suitable protic and aprotic ILs behave in the presence of water in the first place. The present work aims at making an important step by performing a combined experimental and computational study of two selected ILs and their mixtures with water: the aprotic cholinium propionate ([Chl][Pro]) and the protic N-methyl-2-pyrrolidonium propionate ([NMP][Pro]). IR and Raman spectroscopy reveal stronger ion-solvent interactions in [Chl][Pro]-H2O systems compared to [NMP][Pro]-H2O mixtures. This can be explained by the tightly packed ion-pair associations in [NMP][Pro] comprising the protic -N+-H counterpart, which allows the establishment of highly directional and strong interionic hydrogen bonds. The spectral decomposition of the O-D stretching band into three sub-peaks showed that the protic [NMP][Pro] favors the self-association of water molecules. On the other hand, the predominant fraction of water-anion/cation aggregates exists in aprotic [Chl][Pro]. These hydrated systems can be envisaged using quantum-chemical calculations in the following way: H2O[Chl]+H2O[Pro]-H2O and H2O[NMP]+[Pro]-H2O, which implied preferable solvent-shared ion-pair (SIP) configurations for [Chl][Pro]-H2O systems, whereas the contact ion-pair (CIP) state prevails for the [NMP][Pro]-H2O systems. The latter holds even in the water-rich regime. In future work, these findings will be the basis for an understanding of the underlying principles that govern the interactions of ions with bio-molecules in aqueous solutions.
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Affiliation(s)
- Kaushik Kundu
- Department of Inorganic and Physical Chemistry, Indian Institute of Science (IISc), Bangalore 560 012, Karnataka, India
| | - Goutam K Chandra
- Department of Inorganic and Physical Chemistry, Indian Institute of Science (IISc), Bangalore 560 012, Karnataka, India and Department of Physics, National Institute of Technology Calicut, Kozhikode 673601, Kerala, India
| | - Siva Umapathy
- Department of Inorganic and Physical Chemistry, Indian Institute of Science (IISc), Bangalore 560 012, Karnataka, India and Indian Institute of Science Education and Research, Bhopal Bhopal Bypass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India.
| | - Johannes Kiefer
- Technische Thermodynamik and MAPEX Center for Materials and Processes, University of Bremen, 28359 Bremen, Germany.
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Nordness O, Kelkar P, Stadtherr MA, Brennecke JF. Ion dissociation in aqueous 1-alkyl-3-methyl-imidazolium chlorides and the impact of microstructure formation. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1635276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Oscar Nordness
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, USA
| | - Pratik Kelkar
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, USA
| | - Mark A. Stadtherr
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, USA
| | - Joan F. Brennecke
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, USA
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40
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Bertasi F, Pagot G, Vezzù K, Nale A, Pace G, Herve Bang Y, Crivellaro G, Negro E, Di Noto V. Lithiated Nanoparticles Doped with Ionic Liquids as Quasi-Solid Electrolytes for Lithium Batteries. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.03.167] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Wei Q, Zhang M, Zhou D, Li X, Bian H, Fang Y. Ultrafast Hydrogen Bond Exchanging between Water and Anions in Concentrated Ionic Liquid Aqueous Solutions. J Phys Chem B 2019; 123:4766-4775. [PMID: 31082232 DOI: 10.1021/acs.jpcb.9b03504] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mixtures of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) ionic liquids (ILs) and water as a function of IL concentrations have been investigated by Fourier transform infrared (FTIR) spectroscopy and ultrafast two-dimensional IR (2D IR) spectroscopy. FTIR spectra of the mixtures resolve two different types of water species, one interacting with the BF4- anions and the other associated with bulklike water molecules. These two water species are in a dynamic equilibrium through forming different hydrogen bonding configurations which are separated by more than 100 cm-1 in the IR spectra. The structural dynamics of the IL mixtures are further revealed by monitoring the vibrational relaxation dynamics of the OD stretching group of interfacial water molecules hydrogen bonded to BF4- anions. With the increase of the IL bulk concentration, vibrational population and rotational dynamics of the interfacial water molecules can be described by a biexponential decay function and are strongly dependent on the IL concentrations. Furthermore, the ultrafast hydrogen bond exchanging between water and BF4- anions in the ILs are also measured using 2D IR spectroscopy. The average hydrogen bond exchanging rate is determined to be 19 ± 4 ps, which is around 3 times slower than that in the NaBF4 electrolyte aqueous solution. The much slower hydrogen bond exchanging rate indicates that the local structure of ILs and water molecules are strongly mediated by the steric effect of the cationic group in the ILs, which is proposed to be responsible for the formation of the heterogeneous structure in the IL mixtures. By using SCN- as the anionic probe, the structural inhomogeneity in the IL solutions can be confirmed from the distinct rotational dynamics of the SCN-, which is segregated from the rotational dynamics of water molecules in the IL mixtures.
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Affiliation(s)
- Qianshun Wei
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
| | - Miaomiao Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
| | - Dexia Zhou
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
| | - Xiaoqian Li
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
| | - Hongtao Bian
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
| | - Yu Fang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering , Shaanxi Normal University , Xi'an 710119 , China
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Biswas S, Mallik BS. Vibration Spectral Dynamics of Weakly Coordinating Water Molecules near an Anion: FPMD Simulations of an Aqueous Solution of Tetrafluoroborate. J Phys Chem B 2019; 123:2135-2146. [PMID: 30759344 DOI: 10.1021/acs.jpcb.9b00069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The extent to which the ions affect the nearby water molecules will decide the structure-making or breaking nature of those ions in aqueous solutions. The effects of a weakly coordinating anion on the structure, dynamics, and vibrational properties of water molecules are not so significant as compared to an anion capable of making strong ion-water hydrogen bonds. The present work deals with the first-principles molecular dynamics study of an aqueous solution of such a weakly coordinating anion, tetrafluoroborate (BF4-), using dispersion-corrected DFT-based first-principles molecular dynamics (FPMD) simulations. Various structural, dynamical, and spectral properties, such as radial distribution functions (RDFs), rotational dynamics, vibrational density of states (VDOS), hydrogen bond as well as dangling OH autocorrelation functions, and residence dynamics, were calculated to investigate the effects of the anion on nearby water molecules. The process of spectral diffusion was assessed through a time series wavelet transformation of trajectories obtained from FPMD simulations. The first ion-water solvation shell extends up to 5.5 Å, containing around 20 water molecules. The lifetime of the ion-water hydrogen bond is found to be 1.19 ps, whereas the water-water hydrogen bond lifetime is found to be 1.13 ps. Inside the solvation shell, the persistence time of dangling OH chromophores and the average frequency of OH modes inside the solvation shell are found to be more compared to bulk. Three time scales are found for solvation shell OH modes from the frequency-frequency correlation function. A very short time scale is found for the intact ion-water interaction; the short time scale is for the ion-water hydrogen bond, and the long time scale is for escape dynamics of water molecules from the ion solvation shell. From the mean squared displacement, it is found that solvation water molecules diffuse slower than the bulk. However, solvation shell water molecules show faster relaxation from the analysis of rotational anisotropy. Within the longer time scale of spectral diffusion, this process (which is related to various dynamics of the molecules) is not yet complete, as compared to fast anisotropic decay. This fact is similar to the experimental finding of spectral diffusion and anisotropy time scales in the aqueous solution of borohydride anion. The calculated results are also compared with available experimental data wherever possible.
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Affiliation(s)
- Sohag Biswas
- Department of Chemistry , Indian Institute of Technology Hyderabad , Kandi, Sangareddy , 502 285 Telangana , India
| | - Bhabani S Mallik
- Department of Chemistry , Indian Institute of Technology Hyderabad , Kandi, Sangareddy , 502 285 Telangana , India
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Han Q, Wang X, Bynre N. Utilizing Water Activity as a Simple Measure to Understand Hydrophobicity in Ionic Liquids. Front Chem 2019; 7:112. [PMID: 30891443 PMCID: PMC6412151 DOI: 10.3389/fchem.2019.00112] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/12/2019] [Indexed: 12/02/2022] Open
Abstract
Ionic liquids (ILs) are regarded as designable solvents finding use in a variety of applications. One of the challenges of the design and selection process is to understand the ionic liquid properties. In this work, we selected seven ILs containing three types of hydrophilic anions and examined several key properties, which are correlated to hydrophobicity. In particular, we measured the hydrogen bond basicity β and water activity aw of IL and IL-water mixtures, and suggested that these two properties are linearly correlated particularly in hydrated ILs. We then used NMR to evaluate the chemical shift of H2O in hydrated ILs. Correlating the outcomes of each of these techniques with respect to understanding the hydrophobicity of the ILs is discussed. It is shown that water activity aw is the most facile technique to represent and understand hydrophobicity of ILs.
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Affiliation(s)
- Qi Han
- Institute for Frontier Materials, Deakin University, Geelong, VIC, Australia
| | - Xungai Wang
- Institute for Frontier Materials, Deakin University, Geelong, VIC, Australia
| | - Nolene Bynre
- Institute for Frontier Materials, Deakin University, Geelong, VIC, Australia
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Wang H, Cui J, Li H, Zhao Y, Wang J. The effect of cationic structure of ionic liquids on their interactions with 5-hydroxymethylfurfural. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2018.10.093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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45
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Cha S, Lee M, Kim D. Concentration Dependence of Ion Pairing in Imidazolium-Based Ionic Liquid Solutions. Chemphyschem 2019; 20:482-488. [PMID: 30565367 DOI: 10.1002/cphc.201800926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 08/15/2018] [Indexed: 11/10/2022]
Abstract
Infrared vibrational spectroscopy was used to probe concentration-dependent ion pair dissociation of imidazolium-based ionic liquids with three different halide anions (I- , Br- , and Cl- ) in deuterated chloroform. Dissociation of the ion pairs at low concentrations of ionic liquids was found to be the easiest for ionic liquid with Cl- anion, the most electronegative anion among the three investigated. This anomalous trend of ion pair dissociation was explained in terms of varying interaction strength between the solvent (CDCl3 ) and the anions investigated.
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Affiliation(s)
- Seoncheol Cha
- Department of Physics, Sogang University, Seoul, Korea
| | - Minho Lee
- Department of Physics, Sogang University, Seoul, Korea
| | - Doseok Kim
- Department of Physics, Sogang University, Seoul, Korea
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Zheng YZ, Zhou Y, Deng G, Guo R, Chen DF. A combination of FTIR and DFT to study the structure and interaction properties of TSILs and water mixture. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2018.11.068] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Nordness O, Simoni LD, Stadtherr MA, Brennecke JF. Characterization of Aqueous 1-Ethyl-3-Methylimidazolium Ionic Liquids for Calculation of Ion Dissociation. J Phys Chem B 2019; 123:1348-1358. [DOI: 10.1021/acs.jpcb.8b11892] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Oscar Nordness
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Luke D. Simoni
- Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Mark A. Stadtherr
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
| | - Joan F. Brennecke
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, United States
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Yue Y, Wang B, Sheng G, Lai H, Wang S, Chen Z, Hu ZT, Zhao J, Li X. An ultra-high H2S-resistant gold-based imidazolium ionic liquid catalyst for acetylene hydrochlorination. NEW J CHEM 2019. [DOI: 10.1039/c9nj01205b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Enhancement of the sulfur resistance of gold-based catalysts is significantly relevant and highly desirable for the development and large-scale applications of these catalysts.
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Affiliation(s)
- Yuxue Yue
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Bolin Wang
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Gangfeng Sheng
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Huixia Lai
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Saisai Wang
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Zhi Chen
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Zhong-Ting Hu
- Department of Environmental Engineering
- Zhejiang University of Technology
- Hangzhou 310014
- People's Republic of China
| | - Jia Zhao
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
| | - Xiaonian Li
- Industrial Catalysis Institute of Zhejiang University of Technology, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology
- Hangzhou
- People's Republic of China
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Ma C, Laaksonen A, Liu C, Lu X, Ji X. The peculiar effect of water on ionic liquids and deep eutectic solvents. Chem Soc Rev 2018; 47:8685-8720. [PMID: 30298877 DOI: 10.1039/c8cs00325d] [Citation(s) in RCA: 225] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Ionic liquids (ILs) and deep eutectic solvents (DESs) have been suggested as eco-friendly alternatives to organic solvents. A trace amount of water is often unavoidable as impurity, and water is also added on purpose to reduce their problematically high viscosity and lower their high price. Understanding the distinct effects of water on the properties of ILs/DESs is highly important. In this review, we collect published experimental and theoretical results for IL/DES-H2O systems at varied water concentrations and analyze them. Results from mechanistic studies, thermodynamic modelling and advanced experiments are collected and critically discussed. Six commonly studied IL/DES-H2O systems were selected to map experimental observations onto microscopic results obtained in mechanistic studies. A great variety of distinct contours of the excess properties can be observed over the entire compositional range, indicating that the properties of IL/DES-H2O systems are highly unpredictable. Mechanistic studies clearly demonstrate that the added H2O rapidly changes the heterogeneous 3D structures of pure ILs/DESs, leading to very different properties and behaviour. There are similarities between aqueous electrolytes and IL/DES solutions but the bulky and asymmetric organic cations in ILs/DESs do not conform to the standard salt dissolution and hydration concepts. Thermodynamic modelling previously assumes ILs/DESs to be either a neutral ion-pair or completely dissociated ions, neglecting specific ion hydration effects. A new conceptual framework is suggested for thermodynamic modelling of IL/DES-H2O binary systems to enable new technologies for their practical applications.
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Affiliation(s)
- Chunyan Ma
- Energy Engineering, Division of Energy Science, Luleå University of Technology, Luleå, 971 87, Sweden.
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Zhu J, Xu Y, Feng X, Zhu X. A detailed study of physicochemical properties and microstructure of EmimCl-EG deep eutectic solvents: Their influence on SO2 absorption behavior. J IND ENG CHEM 2018. [DOI: 10.1016/j.jiec.2018.06.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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