| Reference | [1]. Spectrochim Acta A Mol Biomol Spectrosc. 2018 Mar 15;193:338-343. doi: 10.1016/j.saa.2017.12.026. Epub 2017 Dec 6.<br />
Temperature- and pressure-dependent infrared spectroscopy of 1-butyl-3-methylimidazolium trifluoromethanesulfonate: A dipolar coupling theory analysis.<br />
Burba CM(1), Chang HC(2).<br />
Author information: (1)Department of Natural Sciences, Northeastern State University, 611 N. Grand Ave., Tahlequah, OK, United States. Electronic address: [email protected]. (2)Department of Chemistry, National Dong Hwa University, Taiwan.<br />
Continued growth and development of ionic liquids requires a thorough understanding of how cation and anion molecular structure defines the liquid structure of the materials as well as the various properties that make them technologically useful. Infrared spectroscopy is frequently used to assess molecular-level interactions among the cations and anions of ionic liquids because the intramolecular vibrational modes of the ions are sensitive to the local potential energy environments in which they reside. Thus, different interaction modes among the ions may lead to different spectroscopic signatures in the vibrational spectra. Charge organization present in ionic liquids, such as 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4mim]CF3SO3), is frequently modeled in terms of a quasicrystalline structure. Highly structured quasilattices enable the dynamic coupling of vibrationally-induced dipole moments to produce optical dispersion and transverse optical-longitudinal optical (TO-LO) splitting of vibrational modes of the ionic liquid. According to dipolar coupling theory, the degree of TO-LO splitting is predicted to have a linear dependence on the number density of the ionic liquid. Both temperature and pressure will affect the number density of the ionic liquid and, therefore, the amount of TO-LO splitting for this mode. Therefore, we test these relationships through temperature- and pressure-dependent FT-IR spectroscopic studies of [C4mim]CF3SO3, focusing on the totally symmetric SO stretching mode for the anion, νs(SO3). Increased temperature decreases the amount of TO-LO splitting for νs(SO3), whereas elevated pressure is found to increase the amount of band splitting. In both cases, the experimental observations follow the general predictions of dipolar coupling theory, thereby supporting the quasilattice model for this ionic liquid.<br />
DOI: 10.1016/j.saa.2017.12.026 PMID: 29268233<br />
<br />
[2]. Biotechnol Prog. 2013 Jul-Aug;29(4):933-42. doi: 10.1002/btpr.1735. Epub 2013 May 2.<br />
Experimental and theoretical investigation of multistage extraction of 1,3-propanediol using the extraction system phosphate/1-butyl-3-methylimidazolium trifluoromethanesulfonate/water.<br />
Müller A(1), Lutze P, Górak A.<br />
Author information: (1)Dept. of Biochemical and Chemical Engineering, Laboratory of Fluid Separations, TU Dortmund University, Dortmund, D-44227, Germany. [email protected]<br />
The separation of 1,3-propanediol from fermentation broth is a challenging and energy-demanding step using conventional unit operations. One alternative process is the use of an aqueous two-phase system incorporating ionic liquids to use synergy effects of both technologies. Within this manuscript, the technical feasibility of the extraction of 1,3-propanediol using the aqueous two-phase system phosphate (salt)/1-butyl-3-methylimidazolium trifluoromethanesulfonate (ionic liquid)/water in a continuously operated process in pilot-scale is presented. The extraction was performed in a multistage mixer-settler unit and successfully modeled with an equilibrium-stage model and correlations to describe the liquid-liquid equilibrium of the salt/ionic liquid/water two-phase system. The developed and validated model was used for a further investigation of the influence of different process parameters in the determined operating window. Theses parameters include the number of stages, the phase ratio, the pH, and the mass fraction of the involved components. The results prove that the phosphate and 1-butyl-3-methylimidazolium trifluoromethanesulfonate mass fraction, the phase ratio, and the number of stages have a considerable influence on the recovery of 1,3-propanediol, whereas the pH value has only a smaller impact. Those results can be used for optimization of the system as well as for targeting future research within this area.<br />
DOI: 10.1002/btpr.1735 PMID: 23554391 [Indexed for MEDLINE]<br />
<br />
[3]. J Phys Chem B. 2008 Sep 4;112(35):11100-5. doi: 10.1021/jp804107y. Epub 2008 Aug 9.<br />
Activity coefficients at infinite dilution measurements for organic solutes and water in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate.<br />
Domańska U(1), Marciniak A.<br />
Author information: (1)Physical Chemistry Division, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland. [email protected]<br />
The activity coefficients at infinite dilution, gamma 13 (infinity) for 32 solutes: alkanes, alkenes, alkynes, cycloalkanes, aromatic hydrocarbons, alcohols, thiophene, tetrahydrofurane, tert-butyl methyl ether, and water in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][CF3SO3] were determined by gas-liquid chromatography at the temperatures from 298.15 to 368.15 K. The partial molar excess enthalpies at infinite dilution values Delta H 1 (E,infinity) were calculated from the experimental gamma 13 (infinity) values obtained over the temperature range. The selectivities for the hexane/benzene, cyclohexane/benzene, n-hexane/thiophene, n-decane/thiophene, cyclohexane/thiophene, toluene/thiophene, and oct-1-ene/thiophene separation problems were calculated from the gamma 13 (infinity). Obtained values were compared to the literature values for the other ionic liquids, NMP, and sulfolane.<br />
DOI: 10.1021/jp804107y PMID: 18693694<br />
<br />
[4]. J Chem Phys. 2008 Sep 7;129(9):094707. doi: 10.1063/1.2965526.<br />
Temperature-programed time-of-flight secondary ion mass spectrometry study of 1-butyl-3-methylimidazolium trifluoromethanesulfonate during glass-liquid transition, crystallization, melting, and solvation.<br />
Souda R(1), Günster J.<br />
Author information: (1)National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. [email protected]<br />
For this study, time-of-flight secondary ion mass spectrometry was used to analyze the molecular orientation of 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([bmim][OTf]) and its interaction with the adsorbed Na and LiI species at temperatures of 150-300 K. A glassy [bmim][OTf] film crystallizes at around 230 K, as observed from the increase in the [bmim](+) yield. LiI and Na adsorbed on the glassy film are solvated, whereas they tend to form islands on a crystalline film. The crystalline surface inertness is ascribable to the termination with the CF(3) and C(4)H(9) groups, whereas the exposure of polar SO(3) and imidazole groups at the glassy film results in the solvation. Surface layering occurs during solvation of LiI on the glassy film in such a way that the [bmim](+) ([OTf](-)) moiety is exposed to the vacuum (oriented to the bulk). The LiI adsorbed on the glassy film is incorporated into the bulk at temperatures higher than 200 K because of the glass-liquid transition. No further uptake of LiI is observed during crystallization, providing a contrast to the results of normal molecular solids such as water and ethanol. The surface layers of the crystal melt at temperatures below the bulk melting point, as confirmed from the dissolution of adsorbed LiI, but the melting layer retains a short-range order similar to the crystal. The [bmim][OTf] can be regarded as a strongly correlated liquid with the combined liquid property and crystal-type local structure. The origin of this behavior is discussed.<br />
DOI: 10.1063/1.2965526 PMID: 19044886<br />
<br />
[5]. Extremophiles. 2016 Jul;20(4):415-24. doi: 10.1007/s00792-016-0832-z. Epub 2016 May 3.<br />
Properties of an ionic liquid-tolerant Bacillus amyloliquefaciens CMW1 and its extracellular protease.<br />
Kurata A(1), Senoo H(2), Ikeda Y(2), Kaida H(2), Matsuhara C(2), Kishimoto N(2).<br />
Author information: (1)Department of Applied Biological Chemistry, Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara, 631-8505, Japan. [email protected]. (2)Department of Applied Biological Chemistry, Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara, 631-8505, Japan.<br />
An ionic liquid-tolerant bacterium, Bacillus amyloliquefaciens CMW1, was isolated from a Japanese fermented soybean paste. Strain CMW1 grew in the presence of 10 % (v/v) 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), a commonly used ionic liquid. Additionally, strain CMW1 grew adequately in the presence of the hydrophilic ionic liquids 10 % (v/v) 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM]CF3SO3) or 2.5 % (v/v) 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIM]CF3SO3). Strain CMW1 produced an extracellular protease (BapIL) in the culture medium. BapIL was stable in the presence of 80 % (v/v) ionic liquids, [EMIM]CF3SO3, [BMIM]Cl, [BMIM]CF3SO3, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, and functioned in 10 % (v/v) these ionic liquids. BapIL was stable at pH 4.0-12.6 or in 4004 mM NaCl solution, and exhibited activity in the presence of 50 % (v/v) hydrophilic or hydrophobic organic solvents. BapIL was completely inhibited by 1 mM PMSF and partially by 5 mM EDTA. BapIL belongs to the true subtilisins according to analysis of the deduced amino acid sequence. We showed that BapIL from the ionic liquid-tolerant B. amyloliquefaciens CMW1 exhibited tolerance to ionic liquid and halo, alkaline, and organic solvents.<br />
DOI: 10.1007/s00792-016-0832-z PMID: 27142029
|
