Mechanism of extractive/oxidative desulfurization using the ionic liquid inimidazole acetate: a computational study.
The dual role of the ionic liquid 1-butyl-3-methyl-imidazolium trifluoroacetic acid ([C4mim]TFA) as an extractant for thiophene (TH) and a catalyst for the oxidation of TH was explored at the molecular level by performing density functional theory (DFT) calculations. The calculated interaction energies demonstrated why [C4mim]TFA is a better extractant for thiophene sulfone (THO2) than for TH. Two pathways were proposed for the oxidation of TH to THO2with [C4mim]TFA acting as a catalyst. In the dominant pathway, a peracid is formed which then oxidizes TH to the sulfoxide and sulfones. The presence of [C4mim]TFA was found to greatly reduce the barrier to the oxidative desulfurization (ODS) of TH using H2O2as an oxidant. Graphical Abstract Possible reaction mechanisms of TH with the aid of [C4mim]TFAᅟ.
College of Chemical Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, People's Republic of China. wanghlu@mail2.sysu.edu.cn.
Hanlu
H
Wang
College of Chemical Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, People's Republic of China.
Mingsheng
M
Xu
College of Chemical Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, People's Republic of China. rujinzhou@126.com.
Rujin
R
Zhou
DFT; Desulfurization; Extraction/oxidation; Imidazole acetate; Ionic liquid