用[BMIM][Cu2Cl3]离子液体萃取脱除汽油中的硫化物

以不同的IL（ionic liquid）/油质量比，采用[BMIM][Cu2Cl3]（[BMIM]=1-butyl-3-methylimidazolium）对模型汽油和商品汽油进行单步和多步萃取脱硫实验；并合成几种具有不同阴离子和阳离子结构的离子液体，评价和比较了离子液体对商品汽油的萃取脱硫性能的影响。实验结果表明，具有较好的水稳定性和常温流动性的[BMIM] [Cu2Cl3]离子液体硫容较高，在IL/油质量比为1∶3时，经多步萃取后，油品中的硫质量分数降至20×10-6～30×10-6，累计脱硫率超过95%。汽油中其他组分对脱硫效果影响很小。[BMIM][Cu2Cl3]与汽油形成稳定的两相系统，分离方便。离子液体脱硫能力可以通过四氯化碳反萃取完全恢复。

Extractive desulfurization from gasoline by [BMIM][Cu2Cl3]

A moisture stable ionic liquid that contains Cu(Ⅰ) was used as solvent for desulfurization from gasoline in this paper. CuC1 was mixed with 1-butyl-3-methylimidazolium (BMIM) chloride according to the molar ratio of 2∶1 to synthesize [BMIM][Cu2Cl3] ionic liquid. [BMIM][Zn2Cl5] and [Et3NH][Cu2Cl3](Et=ethyl) were prepared in the same process. Model oil (dissolving thiophene in the mixture of heptane and toluene) and commercial gasoline were treated by [BMIM][Cu2Cl3] at room temperature. It is found that [BMIM][Cu2Cl3] could remarkably remove sulfur from oil. After six-stage extraction, the S content in the model oil reduces from 650×10-6 to 20×10-6 when the mass ratio of IL/oil is 1∶3. The single stage desulfurization decreases from 37% to 23% with the IL/oil ratio decrease from 1∶2 to 1∶5. It is also shown that the desulfurization ability of [BMIM][Cu2Cl3] from real gasoline is similar to that from model oil. Other components in gasoline have little influence on the desulfurization ability of [BMIM][Cu2Cl3]. [BMIM][Cu2Cl3] can be easily separated because of the biphasic systems of IL/oil formation. The polymerization products of olefin in gasoline are not detected in desulfurization. Desulfurization abilities of [BMIM][Zn2Cl5] or [Et3NH][Cu2Cl3] are lower than that of [BMIM][Cu2Cl3]. Carbon tetrachloride and toluene were used to regenerate the ionic liquid prepared. The regeneration was conducted at mass ratio IL/solvent of 1∶3 and temperature of 75 ℃ with stirring for 30 min. The regeneration results indicate that the sulfur removal capacity of IL is recovered completely by carbon tetrachloride treatment, but toluene shows poor ability to regenerate [BMIM][Cu2Cl3]. CCl4 might be easily seperated from the high boiling point thiophene derivatives absorbed by evaporation or rectification .