title: Insights into the effect of CO2absorption on the ionic mobility of ionic liquids.
abstract: We investigate a comparative effect of CO2absorption on the ionic mobility of two choline based ionic liquids comprising two different anions such as threonine and imidazole. The synthesized ionic liquids were characterized using1H and13C NMR and other spectroscopic techniques. By keeping a common cation and changing the anion from threonine to imidazole both the viscosity and density reduced drastically. We found that [N1,1,6,2OH][Imi] exhibits the highest CO2capture capacity at 20 °C of 5.27 mol of CO2per kg of ionic liquid (1.27 mol of CO2per mol of ionic liquid, 23.26 wt% of CO2) whereas [N1,1,6,2OH][Threo] exhibits 3.6 mol of CO2per kg of ionic liquid (1.05 mol of CO2per mol of ionic liquid, 15.87 wt% of CO2). The activation energy for diffusion is calculated using the Vogel-Fulcher-Tamman (VFT) equation in the form of diffusivity. It was found that the activation energy for the diffusion of [N1,1,6,2OH][Threo] is ∼10 times higher than that of [N1,1,6,2OH][Imi].1H diffusion NMR data revealed that the diffusivity of [N1,1,6,2OH][Imi] is increased after CO2absorption whereas a decrease in diffusivity was observed in the case of [N1,1,6,2OH][Threo]. This anomalous behavior of [N1,1,6,2OH][Imi] was further explained by using DFT calculations.
authors.affiliation: Chemistry of Interfaces, Lulea University of Technology, Lulea-97187, Sweden. shubhankar.bhattacharyya@ltu.se faisha@ltu.se.
authors.forename: Shubhankar
authors.identifier: http://orcid.org/0000-0002-6295-4112
authors.initials: S
authors.lastname: Bhattacharyya
authors.affiliation: Chemistry of Interfaces, Lulea University of Technology, Lulea-97187, Sweden. shubhankar.bhattacharyya@ltu.se faisha@ltu.se and Institute of Physics, Kazan Federal University, 420008 Kazan, Russia.
authors.forename: Andrei
authors.initials: A
authors.lastname: Filippov
authors.affiliation: Chemistry of Interfaces, Lulea University of Technology, Lulea-97187, Sweden. shubhankar.bhattacharyya@ltu.se faisha@ltu.se.
authors.forename: Faiz Ullah
authors.initials: FU
authors.lastname: Shah