1. Phase Transitions, Decomposition Temperatures, Viscosities, and Densities of Phosphonium, Ammonium, and Imidazolium Ionic Liquids with Aprotic Heterocyclic Anions
- Author
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M. Aruni DeSilva, Mauricio Quiroz-Guzman, Han Xia, Joan F. Brennecke, and Joseph J. Fillion
- Subjects
General Chemical Engineering ,Inorganic chemistry ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Decomposition ,0104 chemical sciences ,Ion ,chemistry.chemical_compound ,chemistry ,Ionic liquid ,Melting point ,Phosphonium ,0210 nano-technology ,Glass transition ,Imide - Abstract
Ionic liquids (ILs) with aprotic heterocyclic anions (AHAs) have been developed primarily for CO2 capture applications. However, they have also been considered for cofluid CO2/IL vapor compression refrigeration cycles and for various electrochemical applications. In all of these cases, reducing the viscosity of the IL is of primary importance. Therefore, the focus of this work is tuning the cation to produce AHA ILs with both low viscosities and low melting points. Toward this goal we have synthesized 40 AHA ILs paired with phosphonium, ammonium and imidazolium cations, as well as a number of ILs with the bis(trifluoromethylsulfonyl)imide anion to use for comparison. The azolide anions investigated were 2-cyanopyrrolide, 4-nitropyrazolide, various substituted imidazolides, 1,2,3-triazolide, and tetrazolide. Melting points, glass transition temperatures, and decomposition temperatures were measured for all ILs. Viscosities and densities were measured from 278.15 to 343.15 K and 283.15 to 353.15 K, respecti...
- Published
- 2016