化学学报 ›› 2014, Vol. 72 ›› Issue (11): 1152-1156.DOI: 10.6023/A14080570 上一篇    下一篇

研究通讯

氧化-温控双功能离子液体催化O2氧化模拟柴油脱硫

于凤丽a, 唐会宝a, 柳春玉a, 解从霞a, 于世涛b   

  1. a 青岛科技大学化学与分子工程学院 青岛 266042;
    b 青岛科技大学化工学院 青岛 266042
  • 投稿日期:2014-08-06 发布日期:2014-10-22
  • 通讯作者: 解从霞 E-mail:xiecongxia@126.com
  • 基金资助:

    项目受国家自然科学基金(No. 21176129)、山东省优秀中青年科学家科研奖励基金(No. BS2011NJ008)和青岛市科技发展计划项目(No. 13-1-4-194-jch)资助.

Oxidative Desulfurization of Model Diesel with O2 Catalyzed by Oxidative-thermoregulated Bifunctional Ionic Liquids

Yu Fenglia, Tang Huibaoa, Liu Chunyua, Xie Congxiaa, Yu Shitaob   

  1. a College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042;
    b College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042
  • Received:2014-08-06 Published:2014-10-22
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21176129), the Foundation for Outstanding Young Scientist in Shandong Province (No. BS2011NJ008) and the Project of Basic Research in Qingdao City (No. 13-1-4-194-jch).

将温控结构单元聚醚链和催化氧化基团磷钨酸根共同引入到离子液体的结构中, 合成出一系列不同聚合度的十八胺类氧化-温控双功能离子液体, 并将其应用于催化O2氧化模拟柴油的脱硫反应过程, 实现了反应分离一体化, 并取得了良好的脱硫效果和催化剂循环使用效果. 该类离子液体在甲苯/正十二烷混合溶剂中具有良好的温控性能. 筛选出活性较高的离子液体催化剂, 其聚合度n=111以及烷基碳链为C12. 考察了反应温度、反应时间和氧气压力等因素对脱硫效果的影响. 在优化的反应条件(V(甲苯):V(模拟油)=1:1, T=100 ℃, t=2 h, p(O2)=2.0 MPa)下, DMF萃取一次, 脱硫率接近100%. 催化剂循环使用11次, 脱硫率仍可达到95%以上.

关键词: 功能化离子液体, 温控, 氧化脱硫, 氧气

A series of ammonium oxidative-thermoregulated bifunctional ionic liquids (ILs) have been synthesized by introducing the thermoregulated structural unit (PEG chain) into ammonium cation and using heteropolyanion as catalytic oxidation group. The prepared ionic liquids have the thermoregulated solubility in toluene/n-dodecane mixed solvent. IL/toluene/n-dodecane system owns the feature of "homogeneous at high temperature, heterogeneous at low temperature". The effects of the dosage of the ionic liquid, the polymerization degree of the ionic liquid, and the volume ratio of toluene to n-dodecane on the thermoregulation of the system have been investigated. Model diesel is prepared by dissolving the model sulfur-containing compound thiophene in n-dodecane. By using the ionic liquid as catalyst, the thermoregulated IL/toluene/n-dodecane biphasic system has been used for catalytic oxidative desulfurization of model diesel with O2 as oxidant to achieve the integration of homogeneous reaction and heterogeneous separation. So, the highly efficient catalysis and the simply separation of catalyst are achieved. The selected catalytic system is the polymerization degree of the ionic liquid n=111 and V(toluene):V(model oil)=1:1. The effects of the alkyl chain of the ionic liquid, reaction temperature, reaction time and the pressure of oxygen on the desulfurization rate have been fully investigated. The selected optimal conditions are as follows: the alkyl chain C12, reaction temperature 100 ℃, reaction time 2 h, and the pressure of oxygen 2.0 MPa. Under the optimal conditions, the sulfur in model diesel nearly can be completely removed by using DMF as extraction agent. After the reaction, the catalyst can be automatically precipitated from the oil phase at the room temperature. Therefore, the recycle of the catalyst is easily realized. The recyclability of the ionic liquid catalyst is investigated. The result has showed that the catalyst exhibits very excellent recyclability. Under the above selected reaction conditions, the desulfurization rate still can reach above 95% after 11 recycles of the ionic liquid catalyst.

Key words: task-specific ionic liquids, thermoregulation, oxidative desulfurization, oxygen