Regulating sulfur removal efficiency of fuels by Lewis acidity of ionic liquids

• Published in: Science China. Chemistry 2016-05, Vol.59 (5), p.526-531
• Main Authors: Nie, Yi, Dong, Yuxiao, Gao, Hongshuai, Zhang, Xiangping, Zhang, Suojiang
• Format: Article
• Language: English
• Subjects: Benzothiophene; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; DBT; Desulfurizing; Dibenzothiophene; Fuels; Hydrogen peroxide; Ionic liquids; Rate constants; Substrates; Sulfur; Sulfur removal; 二苯并噻吩; 催化氧化脱硫; 刘易斯; 燃料; 脱硫效率; 表观速率常数; 酸性离子液体
• ISSN: 1674-7291; 1869-1870
• DOI: 10.1007/s11426-016-5563-6

It is urgent to develop a new deep desulfurization process of fuels as the environmental pollution increases seriously. In this work, a series of Lewis acidic ionic liquids （ILs） [C43MPy]Cl/nZnCl2 （n=1, 1.5, 2, 3） were synthesized and used in extraction and catalytic oxidative desulfurization （ECOD） of the fuels. The effects of the Lewis acidity of ILs, the molar ratio of H2O2/sulfur, temperatures, and different substrates including dibenzothiophene （DBT）, benzothiophene （BT） and thiophene （TS）, on sulfur removal were investigated. The results indicated that [C43MPy]Cl/3ZnCl2 presented near 100% DBT removal of model oil under conditions of 323 K, H2O2/DBT molar ratio 6：1. Kinetics for the removal of DBT, BT and TS by the [C43MPy]Cl/3ZnCl2-H2O2 system at 323 K is first-order with the apparent rate constants of 1.1348, 0.2226 and 0.0609 h-1, and the calculated apparent activation energies for DBT, BT and TS were 61.13, 60.66, and 68.14 kJ/mol from 298 to 308 K, re- spectively. After six cycles of the regenerated [C43MPy]Cl/3ZnCl2, the sulfur removal had a slight decrease. [C43MPy]Cl/ 3ZnCl2 showed a good desulfurization performance under optimal conditions.