The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Ana Rodríguez - One of the best experts on this subject based on the ideXlab platform.
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a study on the liquid liquid equilibria of 1 alkyl 3 methylimidazolium Hexafluorophosphate with ethanol and alkanes
Fluid Phase Equilibria, 2008Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:Abstract This work demonstrates the ability of the 1-alkyl-3-methylimidazolium Hexafluorophosphate to act as an extraction solvent in petrochemical processes for the removal of alkanes from their azeotropic mixture with ethanol. LLE (liquid–liquid equilibrium) of the ternary systems hexane + ethanol + 1-hexyl-3-methylimidazolium Hexafluorophosphate (HMIM PF6) or 1-octyl-3-methylimidazolium Hexafluorophosphate (OMIM PF6) and heptane + ethanol + OMIM PF6 are carried out at 298.15 K and atmospheric pressure. Experimental liquid–liquid data are correlated by using different equations. The solute distribution ratio and the selectivity, determined from tie-line data, suggest the efficiency of the ILs used as solvents. A comparison with other IL, in terms of solvent capacity, is included. The liquid–liquid extraction process is simulated by using conventional software and the obtained results are shown.
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phase equilibria of the azeotropic mixture hexane ethyl acetate with ionic liquids at 298 15 k
Journal of Chemical & Engineering Data, 2008Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:This work reports the results of a study on the use of the two ionic liquids as an extraction solvent in the separation of the azeotropic mixture of hexane with ethyl acetate. Experimental densities, speeds of sound, and refractive indices of the binary mixtures of ethyl acetate + hexane or + 1-hexyl-3-methylimidazolium Hexafluorophosphate (HMIM PF6) were determined from (293.15 to 303.15) K, since they are necessary to determine liquid−liquid equilibria. Excess molar volumes, changes of refractive index on mixing, and deviations in isentropic compressibility for the above systems were calculated. Liquid−liquid equilibria (LLE) were determined for the ternary systems hexane + ethyl acetate + HMIM PF6 or 1-octyl-3-methylimidazolium Hexafluorophosphate (OMIM PF6) at 298.15 K and atmospheric pressure. The values of selectivity and distribution ratio were derived from the tie-line data. Experimental liquid−liquid equilibria data were correlated with the NRTL and UNIQUAC equations. These equations were verifie...
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Study on the phase behaviour and thermodynamic properties of ionic liquids containing imidazolium cation with ethanol at several temperatures
The Journal of Chemical Thermodynamics, 2007Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:Abstract Experimental densities, speeds of sound and refractive indices of the binary mixtures of ethanol with MMIM MeSO4 (1,3-dimethylimidazolium methyl sulfate), BMIM MeSO4 (1-butyl-3-methylimidazolium methyl sulfate), BMIM PF6 (1-butyl-3-methylimidazolium Hexafluorophosphate), HMIM PF6 (1-hexyl-3-methylimidazolium Hexafluorophosphate) and OMIM PF6 (1-methyl-3-octylimidazolium Hexafluorophosphate) were determined from T = (293.15 to 303.15) K. Excess molar volumes, changes of refractive index on mixing and deviations in isentropic compressibility for the above systems were calculated. The (liquid + liquid) equilibrium (LLE) data of (IL + ethanol) were carried out experimentally and the NRTL and UNIQUAC correlative equation was applied to these mixtures.
Robin D Rogers - One of the best experts on this subject based on the ideXlab platform.
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liquid clathrate formation in ionic liquid aromatic mixtures
Chemical Communications, 2003Co-Authors: John D Holbrey, Matthew W Reichert, Mark Nieuwenhuyzen, Oonagh Sheppard, Christopher Hardacre, Robin D RogersAbstract:1-Alkyl-3-methylimidazolium containing ionic liquids with Hexafluorophosphate, bis(trifyl)imide, tetrafluoroborate, and chloride anions form liquid clathrates when mixed with aromatic hydrocarbons; in the system 1,3-dimethylimidazolium Hexafluorophosphate-benzene, the aromatic solute could be trapped in the solid state forming a crystalline 2:1 inclusion compound.
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application of ionic liquids as plasticizers for poly methyl methacrylate
Chemical Communications, 2002Co-Authors: Mark P Scott, John D Holbrey, Christopher S Brazel, Michael G Benton, Jimmy W Mays, Robin D RogersAbstract:The room temperature ionic liquid, 1-butyl-3-methylimidazolium Hexafluorophosphate, [C4mim][PF6] was found to be an efficient plasticizer for poly(methyl methacrylate), prepared by in situ radical polymerization in the ionic liquid medium; the polymers have physical characteristics comparable with those containing traditional plasticizers and retain greater thermal stability.
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on the solubilization of water with ethanol in hydrophobic Hexafluorophosphate ionic liquids
Green Chemistry, 2002Co-Authors: Richard P Swatloski, John D Holbrey, Ann E Visser, Matthew W Reichert, Grant A Broker, Lindsy M Farina, Robin D RogersAbstract:The solubility of water in the hydrophobic 1-alkyl-3-methylimidazolium Hexafluorophosphate (alkyl = butyl, hexyl, and octyl) ionic liquids, can be significantly increased in the presence of ethanol as a co-solute. 1-Hexyl-3-methylimidazolium Hexafluorophosphate and 1-octyl-3-methylimidazolium Hexafluorophosphate are completely miscible with ethanol, and immiscible with water, whereas 1-butyl-3-methylimidazolium Hexafluorophosphate is totally miscible with aqueous ethanol only between 0.5–0.9 mole fraction ethanol at 25 °C. At higher and lower mole fraction of ethanol, the aqueous and IL components are only partially miscible and a biphasic system is obtained upon mixing equal volumes of the IL and aqueous ethanol. The observation of a large range of total miscibility between water and the IL in the three-component system has important implications for purifications and separations from IL.
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Room temperature ionic liquids as novel media for 'clean' liquid-liquid extraction
Chemical Communications, 1998Co-Authors: Jonathan G. Huddleston, A. E. Visser, Richard P Swatloski, Heather D. Willauer, Robin D RogersAbstract:The partitioning of simple, substituted-benzene derivatives between water and the room temperature ionic liquid, butylmethylimidazolium Hexafluorophosphate, is based on the solutes’ charged state or relative hydrophobicity; room temperature ionic liquids thus may be suitable candidates for replacement of volatile organic solvents in liquid–liquid extraction processes.
Xiashi Zhu - One of the best experts on this subject based on the ideXlab platform.
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determination of rhodamine b pigment in food samples by ionic liquid coated magnetic core shell fe 3 o 4 sio 2 nanoparticles coupled with fluorescence spectrophotometry
Science Journal of Chemistry, 2017Co-Authors: Almojtaba Abd Alkhalig Ahmed Bakheet, Xiashi ZhuAbstract:The Ionic liquids (IL) 1-octyl-3-methylimidazole Hexafluorophosphate ([OMIM]PF6) was selected from three ILs along with (1-butyl-3-methylimidazole Hexafluorophosphate ([BMIM]PF6), 1-hexyl-3-methyl-imidazole hexafluoro-phosphate ([HMIM]PF6), were coated by Fe3O4@SiO2 nanoparticles with core-shell structure to prepare magnetic solid phase extraction agent (Fe3O4@SiO2@IL) and establish a new method of magnetic solid phase extraction (MSPE) coupled with Fluorescence spectrophotometry for separation/analysis of Rhodamine B. The results showed that Rhodamine B was adsorbed rapidly byFe3O4@SiO2@[OMIM]PF6 and eluted by ethanol. Under the optimal conditions the linear range, detection limit (DL), correlation coefficient (R) and relative standard deviation (RSD) were found to be 0.40-140.00 g L-1, 0.06g L-1, 0.9993 and 0.45% (n=3, c=10.00 µg L-1), respectively. The pre-concentration factor of the proposed method was 25-fold. The Fe3O4@SiO2 NPs can be used repeatedly for 10 times. This method has been applied to the determination of Rhodamine B in food samples.
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Magnetic solid phase extraction using ionic liquid-coated core-shell magnetic nanoparticles followed by high-performance liquid chromatography for determination of Rhodamine B in food samples
Food Chemistry, 2016Co-Authors: Jieping Chen, Xiashi ZhuAbstract:Three hydrophobic ionic liquids (ILs) (1-butyl-3-methylimidazole Hexafluorophosphate ([BMIM]PF6), 1-hexyl-3-methyl-imidazole hexafluoro-phosphate ([HMIM]PF6), and 1-octyl-3-methylimidazole Hexafluorophosphate ([OMIM]PF6)) were used to coat Fe3O4at SiO2nanoparticles (NPs) with core-shell structures to prepare magnetic solid phase extraction (MSPE) agents (Fe3O4at SiO2at IL). A novel method of MSPE coupled with high-performance liquid chromatography for the separation/analysis of Rhodamine B was then established. The results showed that Rhodamine B was adsorbed rapidly on Fe3O4at SiO2at [OMIM]PF6and was released using ethanol. Under optimal conditions, the pre-concentration factor for the proposed method was 25. The linear range, limit of detection (LOD), correlation coefficient (R), and relative standard deviation (RSD) were found to be 0.50-150.00 μg L-1, 0.08 μg L-1, 0.9999, and 0.51% (n = 3, c = 10.00 μg L-1), respectively. The Fe3O4at SiO2NPs could be re-used up to 10 times. The method was successfully applied to the determination of Rhodamine B in food samples.
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ionic liquid coated magnetic core shell fe3o4 sio2 nanoparticles for the separation analysis of linuron in food samples
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2015Co-Authors: Jieping Chen, Xiashi ZhuAbstract:Three hydrophobic ionic liquids (ILs) including 1-butyl-3-methylimidazole Hexafluorophosphate ([BMIM]PF6), 1-hexyl-3-methyl-imidazole Hexafluorophosphate ([HMIM]PF6), and 1-octyl-3-methylimidazole hexafluoro-phosphate ([OMIM]PF6) coated Fe3O4@SiO2 nanoparticles with core-shell structure to prepare magnetic solid phase extraction agent (Fe3O4@SiO2@ILs) and establish a new method of magnetic solid phase extraction (MSPE) coupled with UV spectrometry for separation/analysis of linuron. The results showed that linuron was adsorbed rapidly by Fe3O4@SiO2@[OMIM]PF6 and eluanted by ethanol. Under the optimal conditions, preconcentration factor of the proposed method was 10-fold. The linear range, detection limit, correlation coefficient (R) and relative standard deviation (RSD) were found to be 0.04-20.00 μg mL(-1), 5.0 ng mL(-1), 0.9993 and 2.8% (n=3, c=4.00 μg mL(-1)), respectively. The Fe3O4@SiO2 nanoparticles could be used repeatedly for 10 times. This proposed method has been successfully applied to the determination of linuron in food samples.
Ana B. Pereiro - One of the best experts on this subject based on the ideXlab platform.
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a study on the liquid liquid equilibria of 1 alkyl 3 methylimidazolium Hexafluorophosphate with ethanol and alkanes
Fluid Phase Equilibria, 2008Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:Abstract This work demonstrates the ability of the 1-alkyl-3-methylimidazolium Hexafluorophosphate to act as an extraction solvent in petrochemical processes for the removal of alkanes from their azeotropic mixture with ethanol. LLE (liquid–liquid equilibrium) of the ternary systems hexane + ethanol + 1-hexyl-3-methylimidazolium Hexafluorophosphate (HMIM PF6) or 1-octyl-3-methylimidazolium Hexafluorophosphate (OMIM PF6) and heptane + ethanol + OMIM PF6 are carried out at 298.15 K and atmospheric pressure. Experimental liquid–liquid data are correlated by using different equations. The solute distribution ratio and the selectivity, determined from tie-line data, suggest the efficiency of the ILs used as solvents. A comparison with other IL, in terms of solvent capacity, is included. The liquid–liquid extraction process is simulated by using conventional software and the obtained results are shown.
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phase equilibria of the azeotropic mixture hexane ethyl acetate with ionic liquids at 298 15 k
Journal of Chemical & Engineering Data, 2008Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:This work reports the results of a study on the use of the two ionic liquids as an extraction solvent in the separation of the azeotropic mixture of hexane with ethyl acetate. Experimental densities, speeds of sound, and refractive indices of the binary mixtures of ethyl acetate + hexane or + 1-hexyl-3-methylimidazolium Hexafluorophosphate (HMIM PF6) were determined from (293.15 to 303.15) K, since they are necessary to determine liquid−liquid equilibria. Excess molar volumes, changes of refractive index on mixing, and deviations in isentropic compressibility for the above systems were calculated. Liquid−liquid equilibria (LLE) were determined for the ternary systems hexane + ethyl acetate + HMIM PF6 or 1-octyl-3-methylimidazolium Hexafluorophosphate (OMIM PF6) at 298.15 K and atmospheric pressure. The values of selectivity and distribution ratio were derived from the tie-line data. Experimental liquid−liquid equilibria data were correlated with the NRTL and UNIQUAC equations. These equations were verifie...
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Study on the phase behaviour and thermodynamic properties of ionic liquids containing imidazolium cation with ethanol at several temperatures
The Journal of Chemical Thermodynamics, 2007Co-Authors: Ana B. Pereiro, Ana RodríguezAbstract:Abstract Experimental densities, speeds of sound and refractive indices of the binary mixtures of ethanol with MMIM MeSO4 (1,3-dimethylimidazolium methyl sulfate), BMIM MeSO4 (1-butyl-3-methylimidazolium methyl sulfate), BMIM PF6 (1-butyl-3-methylimidazolium Hexafluorophosphate), HMIM PF6 (1-hexyl-3-methylimidazolium Hexafluorophosphate) and OMIM PF6 (1-methyl-3-octylimidazolium Hexafluorophosphate) were determined from T = (293.15 to 303.15) K. Excess molar volumes, changes of refractive index on mixing and deviations in isentropic compressibility for the above systems were calculated. The (liquid + liquid) equilibrium (LLE) data of (IL + ethanol) were carried out experimentally and the NRTL and UNIQUAC correlative equation was applied to these mixtures.
Yongmin Liang - One of the best experts on this subject based on the ideXlab platform.
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alkyl imidazolium ionic liquids as friction reduction and anti wear additive in polyurea grease for steel steel contacts
Tribology Letters, 2010Co-Authors: Meirong Cai, Zhu Zhao, Yongmin Liang, Feng Zhou, Weimin LiuAbstract:Five room temperature ionic liquids (ILs), 1-butyl-3-methylimidazolium Hexafluorophosphate (L-P104), 1-hexyl-3-methylimidazolium Hexafluorophosphate (L-P106), 1-octyl-3-methylimidazolium Hexafluorophosphate (L-P108), 1-decyl-3-methylimidazolium Hexafluorophosphate (L-P110), and 1-hexyl-3-methylimidazolium tetrafluoroborate (LB106) were studied as 1 wt% additives of polyurea grease for steel/steel contacts. Their tribological behaviors as additives of polyurea grease for steel/steel contacts were evaluated on an Optimol SRV-IV oscillating reciprocating friction and wear tester and an MRS-1J (G) four-ball tester at room and high temperatures. The friction test results showed that the ILs, as 1 wt% additives in polyurea grease for steel/steel contacts, had better friction reduction and anti-wear properties at high temperature than at room temperature, and ILs can significantly improve the friction reduction and anti-wear properties of polyurea grease compared with base grease containing 1 wt% of zinc dialkyldithiophosphate (T204). The excellent tribological properties are attributed to the formation of a surface protective film composed of FeF2, nitrides, and compound containing the P–O bonding on the lubricated metal surface by a tribochemical reaction. The ordered adsorbed films and good miscibility of ILs with the base grease also contributed to the excellent tribological properties. Wear mechanisms and worn steel surfaces were studied by a PHI-5702 multifunctional X-ray photoelectron spectrometer and a JSM-5600LV scanning electron microscope.
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effect of the functional groups in ionic liquid molecules on the friction and wear behavior of aluminum alloy in lubricated aluminum on steel contact
Tribology International, 2005Co-Authors: Zonggang Mu, Feng Zhou, Shuxiang Zhang, Yongmin LiangAbstract:Abstract Four imidazolium-based room temperature ionic liquids containing phosphonyl functional groups, i.e. 1-(3′- O , O -diethylphosphonyl- n -propyl)-3-alkylimidazolium tetrafluoroborates and Hexafluorophosphates, were synthesized. The physical properties of the resulting synthetic products were evaluated, and their tribological behaviors as the lubricants for an aluminum-on-steel sliding system were evaluated on an oscillating friction and wear tester, with the emphasis being placed on the effect of the O , O -diethylphosphonyl groups in the ionic liquid molecules on the tribological behaviors. Thus the friction and tests were conducted at a frequency of 25 Hz, a sliding amplitude of 1 mm, and for a duration of 30 min. The worn aluminum surface was analyzed by means of scanning electron microscopy, energy dispersive X-ray analysis, and X-ray photoelectron spectroscopy. It was found that the synthesized ionic liquids had better friction-reducing and anti-wear ability for the aluminum-on-steel system than their nonfunctionalized courterparts (1-ethyl-3-hexylimidazolium tetrafluoroborate, coded as L206, and 1-propyl-3-octylimidazolium Hexafluorophosphate, coded as LP308). Especially, they had much better load-carrying capacity than L206 and LP308. The tribological behaviors of the synthetic lubricants were dependent on both the anions and the side-substituted alkyl chains attached to the imidazolium cations. Moreover, physical adsorption and complicated tribochemical reactions were involved during the sliding process of the Al-on-steel system under the lubrication of the synthetic functionalized ionic liquids, which led to the generation of physically adsorbing and chemically reacting films composed of five-member-ring complex compounds, metal fluorides, nitrogen oxide, and FePO 4 on the rubbed Al surface. Those physically adsorbing and chemically reacting films contributed to effectively decrease the friction and wear of the aluminum sliding against steel.
