Add time:08/04/2019         Source:sciencedirect.com

Basic 2,4-pentanedionate anion is one of candidates for task-specific ionic liquids as CO2 chemical absorbents. However, there have been few reports on not only CO2 absorption but also physicochemical properties of 2,4-pentanedionate ionic liquids. In this study, we prepared 1-ethyl-3-methylimidazolium ionic liquids with 2,4-pentanedionate and its fluorine derivatives, i.e., 1-ethyl-3-methylimidazolium 2,4-pentanedionate ([C2mim][acac]), 1-ethyl-3-methylimidazolium 1,1,1-trifluoro-2,4-pentanedionate ([C2mim][tfacac]), and 1-ethyl-3-methylimidazolium 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate ([C2mim][hfacac]). A comparison of 1H NMR spectra among the above and three conventional ionic liquids, 1-ethyl-3-methylimidazolium acetate ([C2mim][AcO]), 1-ethyl-3-methylimidazolium 2,2,2-trifluoroacetate ([C2mim][TFA]), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][Tf2N]), showed that the hydrogen atom at the 2-position of [C2mim]+ cation (H2c) interacts with the anions, and the strength of the interaction increases in the order of [Tf2N]– < [TFA]– ≈ [tfacac]– ≈ [hfacac]– < [acac]– < [AcO]–. [C2mim][acac] chemically absorbed CO2 as well as [C2mim][AcO] at atmospheric pressure, although the CO2 solubility of the former was lower than the latter. On the other hand, [C2mim][Tf2N], [C2mim][TFA], [C2mim][tfacac], and [C2mim][hfacac] absorbed only a negligible amount of CO2 under the same conditions. The smaller chemisorption of [C2mim][acac] is attributable to the weaker interactions of the H2c atom with the oxygen atoms of [acac]–. The stronger interaction between the cation and anion in the ionic liquids allows to draw the H2c atom at the initial stage of CO2 chemisorption.

We also recommend Trading Suppliers and Manufacturers of 3-METHYL-1-(2,2,2-TRIFLUORO-ETHYL)-1H-PYRAZOLE-4-CARBOXYLIC ACID (cas 113100-55-3). Pls Click Website Link as below: cas 113100-55-3 suppliers