Preparation Of Desulfurizer Based On Ionic Liauid And Its Desulfurization Performance To Thiophenes In Fuel Oil

There would be many toxic substances after combusted of sulfides in the fuel oil, resulting in environment pollution. Conventional hydrodesulfurization(HDS) had technical limitations for the ultra-low sulfur content oil requirement today, so the non-HDS technologies developed quickly, Among them, the extraction desulfurization with ionic liquid has attracted considerable attentions in recent years. According to the thiophenes’chemistry properties, we prepared three kinds of novel desulfurizers, i.e. imidazolium ionic liquid-transition metal chloride mixtures, imidazolium poly-ionic liquid porous materials, and triphenyl methyl chloride-Lewis acid extractants, and studied their desulfurization performance. The primary work and results of this dissertation are as follows:1, Based on the fact that imidazolium ionic liquid is a soft Lewis acid, transition metal is a hard or border Lewis acid, and thiophenes have both soft and hard base centers, we make a series of IL-MCln extractants by dissolving different transition metal chlorides, i.e. FeCl3, CuCl, ZnCl2, CuCl2, into [BMIM][BF4], and studied their desulfurization performance with the following results:(1) compared to the original [BMMIM][BF4], the desulfurization performance of IL-MCln extractants increased greatly due to the synergetic complexing effect of imidazolium cation and transition metal ions with thiophenes;(2) the desulfurization performance of ILs-MCln extractants follows the order:FeCl3>CuCl>ZnCl2>CuCl2, and the best performance was found for [BMIM][BF4]-FeCl3with its S-distribution coefficient is2.36folds in comparison with the neat ionic liquid;(3) the extractive selectivity of IL-MCln for the organic sulfides is T>BT>DBT, which is opposite to that of neat IL, and contrast the dominant role of the metallic ions dissolved in IL.2, Some poly-ionic liquids (PILs) are designed and prepared by different methods, their structure is characterized and desulfurization performance is tested. The porous PILs prepared include poly vinylethylimidazolium based PILs and urotropine crosslinked by chlorinated paraffin and chlorinated rubber. However, they all showed negligible desulfurization performance, indicating that the composition and pore structure was not suitable for adsorbing thiophenes.3, The carbonium pseudo ionic liquids(CPILs), e.g.[Ph3C]+-[FeCl4]- and Ph2COâ†'FeCl3can be formed when triphenylchloromethane and diphenyl ketone mixed with Lewis acids MCln, as such the hardness of MCln would decrease and their complexation with thiophenes would increase accordingly. It is found that (1) for [Ph3C]+[MCln+1]-series extractants, their desulfurization order is FeCl3>AlCl3>>ZnCl2～CuCl, which is determined by the hardness and strength of Lewis acidity of MCln, herein [Ph3C]+was a softer acid compared to metal chlorides and thus had a more stable complexation with thiophens;(2)[Ph3C]+[MCln+1]-had an excellent desulfurization performance with the selectivity order of BT>DBT, implying that these ILs were border acid, and had a stronger complexation with harder BT;(3) the carboniun has a large steric hindrance, and would not react with thiophenes, and thus these extractants will not be consumed in the recycling uses;(4) IR and13C NMR proved the formation of [Ph3C]+in the extractants;(5) diphenyl ketone-ferric chloride complex howed a little lower desulfurization performance than [Ph3C]+-[FeCl4]-, and some diphenyl ketone would dissolve in the model oil.