(462j) Solvatochromic Evaluation of Hydrophobic Deep Eutectic Solvents
- Conference: AIChE Annual Meeting
- Year: 2018
- Proceeding: 2018 AIChE Annual Meeting
- Group: Topical Conference: Innovations of Green Process Engineering for Sustainable Energy and Environment
- Time: Wednesday, October 31, 2018 - 10:15am-10:30am
Solvatochromic methods of analysis are useful for measurements of a solventâs physical properties such as dipolizability, hydrogen bond donating ability, and hydrogen bond accepting ability. H-bond characteristics will be measured using betaine dyes in a UV-VIS. The solvatochromic method was developed in the 1980s and has been applied for IL and DES. Reichardtâs dye or betaine dye 30 (2,6-diphenyl-4-(2,4,6-triphenylpyridinium- 1-yl)phenolate) is one of the most widely used solvatochromic probes, however, acidic conditions will strongly affect its solvatochromic nature. Since, the goal of this project is to characterize HDES, where HBAs are long chain acids, Reichardtâs dye 33 (2,6-dichloro-4-(2,4,6-triphenylpyridinium1-yl)phenolate) will be chosen for this project instead of dye 30. Kamlet-Taft (KT) parameters will be evaluated for hydrophobic DES. The KT Î² parameter provides H-bond accepting ability of HDES. This parameter will be obtained by solvatochromic method by comparing solvent-induced shifts of the absorption bands of probes. Kamlet and Taft proposed probes, 4-nitroaniline/N,N-diethyl-4-nitroaniline will be used in this project, since they are the most commonly used KT probes for ILs and DES. A lower value of Î² is expected as the formation of HDES through establishment of H-bonds increases the capacity of the HDES to engage in further H-bonds network with HBD. In this paper, effects of anion, aliphatic chain length, and acidic hydrogen bond donor will be evaluated for Î² parameter. Solvatochromic parameters will then be used to compare solvent physical properties with that of the HBA and HBD components.