Deep removal of sulfur from real diesel by catalytic oxidation with halogen-free ionic liquid

摘要

A halogen-free task-specific ionic liquid (TSIL) of 1-(2-carboxylic acid) ethyl-3-methylimidazolium bisul-fate ([(CH_2)_2COO Hrnim] [HSO_4]) is applied for deep oxidative desulfurization of real diesel as a catalyst and reaction media. The sulfur level of real diesel can be reduced from 200 to 20.5 μg/g at room temperature with small amount of ionic liquid using H_2O_2 as an oxidant. The used ionic liquid can be easily recycled and no obvious decrease in catalytic activity can be found after recycling five times.