• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3190-3194
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• 2010

Mixed electrolytes formed by the combination of 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (BMP-TFSI) ionic liquid and standard liquid electrolyte are prepared and characterized. Linear sweep voltammetry measurements demonstrate that these mixed systems exhibit a wide electrochemical stability window, allowing them to be suitable electrolyte for carbonaceous anode-based lithium-ion batteries. Lithium-ion cells composed of graphite anode and $LiCoO_2$ cathode are assembled using the mixed electrolytes, and their cycling performances are evaluated. The cell containing proper content of BMP-TFSI shows good cycling performance comparable to that of a cell assembled with organic electrolyte. The presence of BMP-TFSI in the mixed electrolyte contributes to the reduction of the flammability of electrolyte solution and the improvement of the thermal stability of charged $Li_{1-x}CoO_2$ in the electrolyte solution.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1227-1228
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• 2012

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3149-3151
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• 2011

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4258-4260
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• 2012

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1925-1926
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• 2007

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.477-483
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• 2006

Ionic liquids in the form of organic salts are being widely used as new solvent media. In this paper three positional isomers, o-amino benzoic acid, m-amino benzoic acid, and p-amino benzoic acids were separated with four different ionic liquids as mobile phase additives using high performance liquid chromatography (HPLC). The following ionic liquids were used: 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIm][$BF_{4}$]), 1-ethyl-3-methylimidazolium methylsulfate ([EMIm][MS]), and 1-octyl-3-methylimidazolium methylsulfate ([OMIm][MS]). The effects of the alkyl group length on the imidazolium ring and its counterion, and the concentrations of the ionic liquids on the retention factors and resolutions of amino benzoic acid isomers were tested. The results of the separations with ionic liquids as the eluents were better than those without ionic liquids. Excellent separations of the three isomers were achieved using 2.0-8.0 mM/L [OMIm][MS] and 1.0-8.0 mM/L [EMIm][MS] as the eluent modifiers.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2724-2730
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• 2012

A new heterogeneous acidic catalyst was successfully prepared by impregnation of silica (Aerosil 300) by an acidic ionic liquid, named 1-(4-sulfonic acid)butylpyridinium hydrogen sulfate [$PYC_4SO_3H$][$HSO_4$], and characterized using FT-IR spectroscopy, the $N_2$ adsorption/desorption analysis (BET), thermal analysis (TG/DTG), and X-ray diffraction (XRD) techniques. The amount of loaded acidic ionic liquid on Aerosil 300 support was determined by acid-base titration. This new solid acidic supported heterogeneous catalyst exhibits excellent activity in the synthesis of 2-aryl-2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with aromatic aldehydes under solvent-free conditions and the desired products were obtained in very short reaction times with high yields. This catalyst has the advantages of an easy catalyst separation from the reaction medium and lower problems of corrosion. Recycling of the catalyst and avoidance of using harmful organic solvent are other advantages of this simple procedure.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.645-648
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• 2011

Hydrazine which has been used as monopropellant shows high performance, but because of its high toxicity research for new green propellant that could replace hydrazine is going on. Ionic liquid propellant that is one of the green propellant has lower toxicity, higher specific impulse, and higher density than hydrazine. To design the thruster which use Hydroxylamine Nitrate (HAN), one of ionic liquid propellant, as a propellant, a quantity of catalyst for full decomposition of a propellant is needed. In this study, reference point for HAN thruster design could be suggested through a design of a small scale thruster which used HAN propellant, and propellant decomposition capability evaluation with characteristic velocity efficiency.

• Journal of Electrochemical Science and Technology
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• v.2 no.1
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• pp.8-13
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• 2011

Interfacial compatibility between the Si-Cu electrode and diluted ionic liquid electrolyte containing 50 vol.% of 1M lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/1-methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide (MPP-TFSI) and 50 vol.% dimethyl carbonate (DMC) in a lithium cell and dilution effect on surface chemistry are examined. ex-situ ATR FTIR analysis results reveal that the surface of the Si-Cu electrode cycled in the diluted ionic liquid electrolyte is effectively passivated with the SEI layer mainly composed of carboxylate salts-containing polymeric compounds produced by the decomposition of DMC. Surface species by the decomposition of TFSI anion and MPP cation are found to be relatively in a very low concentration level. Passivation of electrode surface with the SEI species contributes to protect from further interfacial reactions and to preserve the electrode structure over 200 cycles, delivering discharge capacity of > 1670 $mAhg^{-1}$ and capacity retention of 88% of maximum discharge capacity.

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.345-354
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• 2006

Ionic liquids are alternative reaction media of increasing interest and are regarded as an eco-friendly alternatives, of potential use in place of the volatile organic solvents typically used in current chemical processing methods. They are emerging as the smart and excellent solvents, which are made of positive and negative ions that they are liquids near room temperature. The nucleophilic substitution reaction is one of the important method for inserting functional groups into a carbon skeleton. Many nucleophilic substitution reactions have been found with enhanced reactivity and selectivity in ionic liquid. In this review, some recent interesting results of nucleophilic substitution reactions such as hydroxylations, ether cleavages, carbon-X (X= carbon, oxygen, nitrogen, fluorine) bond forming reactions, and ring opening of epoxides in ionic liquids are discussed.