离子液体萃取耦合NaBH4还原/电化学再生燃油脱硫方法研究

The desulfurization of fuel oil is an important way to alleviate the increasingly serious environmental problem sucn as haze, acid rain etc. NaBH4 reduction/electrochemical regeneration method is a very promising fuel oil desulfurization method. However, the hydrogen evolution reaction and the oxygen evolution reaction during pulse electrolysis became the bottleneck of the industrial application of NaBH4 reduction/electrochemical regeneration method. In this project the ionic liquids meeting the functional requirements will be designed and synthesized for fuel oil desulfurization by NaBH4 reduction/electrochemical regeneration method. The ionic liquids will play a dual role during the course of desulfurization: on one hand, the ionic liquids can be used as the electrolyte to avoid the hydrogen evolution reaction and the oxygen evolution reaction during pulse electrolysis; on the other hand, the ionic liquids can be used as the extractants for separating organic sulfides from fuel oil to improve the desulfurization efficiency. The influence of the structure of ionic liquids, pulse parameters and reaction conditions on the yield of NaBH4 from the pulse electrolysis of NaBO2 will be studied. The desulfurization mechanism of ionic liquid extraction coupling with NaBH4 reduction method and the influence of the structure of ionic liquids and reaction conditions on desulfurization efficiency will be investigated. Then a novel method of ionic liquid extraction coupling with NaBH4 reduction/electrochemical regeneration for fuel oil desulfurization will be established. This study aims to provide scientific basis and data support for the preparation of NaBH4 from the pulse electrolysis of NaBO2 in ionic liquids and the desulfurization method of ionic liquid extraction coupling with NaBH4 reduction, and to provide a novel method for fuel oil desulfurization industry.

燃油脱硫是缓解雾霾、酸雨等环境问题的重要途径之一。NaBH4还原/电化学再生法是一种非常具有应用前景的燃油脱硫方法。然而，脉冲电解过程的析氢反应和析氧反应成为制约该脱硫方法工业应用的瓶颈。本项目拟设计合成满足功能要求的离子液体，用于NaBH4还原/电化学再生燃油脱硫过程。离子液体承担双重作用：一方面，作为脉冲电解过程的电解液，以避免析氢反应和析氧反应；另一方面，作为燃油中有机硫化物的萃取剂，以提高脱硫效率。研究离子液体结构、脉冲参数及反应条件对脉冲电解NaBO2制备NaBH4产率的影响机制，考察离子液体萃取耦合NaBH4还原脱硫机理及离子液体结构、反应条件对脱硫效率的影响机制，从而建立离子液体萃取耦合NaBH4还原/电化学再生燃油脱硫方法。本项目的研究将为离子液体中脉冲电解NaBO2制备NaBH4和离子液体萃取耦合NaBH4还原脱硫提供科学依据和数据支撑，为燃油脱硫工业提供新方法。

燃油脱硫是缓解雾霾、酸雨等环境问题的重要途径之一。本研究以NaBH4为还原剂，离子液体或低共熔溶剂为萃取剂，建立萃取耦合还原脱硫方法。并在萃取耦合还原脱硫法的基础上，结合脉冲电解NaBO2制备NaBH4方法，建立了离子液体萃取耦合NaBH4还原/电化学再生燃油脱硫新方法。研究工作主要包括三部分内容：（1）以离子液体1-丁基-1-甲基吡咯烷三氟甲磺酸作为萃取剂，通过离子液体萃取耦合NaBH4还原法对燃油进行脱硫。对脱硫过程反应条件进行了优化，研究了脱硫反应机理，并对离子液体的再生利用性能进行了考察。结果表明，在最佳的反应条件下，模拟燃油的脱硫效率达到97.2%，实际燃油的脱硫效率为93.3%。有机硫化物的脱硫活性顺序为：苯并噻吩（二苯并噻吩）> 3-甲基苯并噻吩 > 4, 6-二甲基二苯并噻吩。（2）合成离子液体N, N-二乙基-N-甲基-N-(2-甲氧基乙基)铵基双(三氟甲基磺酰)亚胺和N-甲基-N-（2-甲氧基乙基）吡咯烷双氟磺酰亚胺，用于离子液体萃取耦合NaBH4还原/电化学再生燃油脱硫过程。通过循环伏安法确定了电解电压范围；通过单因素实验和正交试验考察了脉冲参数、离子液体/油体积比等因素对脱硫效率的影响；研究了脱硫机理及反应动力学；考察了离子液体的再生利用性能。结果表明，在最佳条件下，模拟燃油的脱硫效率达到97%以上，离子液体再生性能良好。（3）以基于四丁基氯化铵的低共熔溶剂为萃取剂，通过低共熔溶剂萃取耦合NaBH4还原法对燃油进行脱硫。研究了低共熔溶剂对硼化镍颗粒粒径和比表面积的影响。通过单因素实验和正交试验考察了反应条件对脱硫效率的影响；研究了脱硫机理及反应动力学；考察了低共熔溶剂的再生利用性能。结果表明，低共熔溶剂中制备的硼化镍粒径更小，比表面积更高。在最佳条件下，模拟燃油脱硫效率达到97%以上。