Ionic Liquids And Gasoline Desulfurization

With the increasingly stringent national environmental rules, the production of low sulfur gasoline has become an urgent task of the petroleum refining industry in the 21st century. The catalytic cracking (FCC) gasoline accounts for about 80% of the total gasoline production in China. To achieve the low sulfur gasoline, the sulfur content in FCC gasoline must be reduced. There are one-time large investment and high operation cost problems in the traditional desulfurization technology. It is the first imperative to carry out research in FCC gasoline desulfurization technology for the petroleum refining industry. As a new green solvent, ionic liquids have broad application prospects on desulfurization of motor fuel.In this thesis, the preparation of ionic liquids and the performances of desulfurization using ionic liquids was mainly studied.Firstly, the ionic liquids of [BMIMJBr and [BMIM]BF4 were synthesized with the microwave method. Its IR was characterized. The results of single-factor experiments showed that the optimum conditions are on [Bmim]Br synthesis were the microwave power 320W, the intermittent reaction time 100s,the charge ratio 1.1:1,in batches by adding N-methyl-imidazole. The results of single-factor experiments showed that the optimum conditions are on [BMIM]BF4 synthesis were the microwave power 320W, the intermittent reaction time 100s, distilled water as solvent. The compounds was characterized by IR.At the same time, triethylamine hydrochloride salts ionic liquids were synthesized by one-step synthesis, its solubility and viscosity were studied.Secondly, the performances of desulfurization using laboratory preparation of ionic liquids was studied. The experiment results are as shown below:1.The desulfurization rate of oxidation was significantly higher than the direct extraction method using ionic liquids [BMIM]BF4. The best extraction condition of oxidative desulfurization is that catalyst-oil ratio v(IL):v(oil)=0.8,30 min oxidation time,50℃oxidation temperature, Volume of peroxide of hydrogen v=2.5mL, desulfurization rate of 87.1% can be attained. [BMIM]BF4 has good performance for repeated use, be reused five times desulfurization rate is almost unchanged.2. The results of single-factor experiments showed that the optimum conditions are on desulfurization experiment were extraction temperature 50℃, catalyst-oil ratio v(IL):v(oil)=0.08, extraction time 50min, standing for 15 min after reaction.Based on the single-factor experiments, some factors affecting the desulfurization rate were evaluated by Plackett-Burman design, the result showed that catalyst-oil ratio, reaction time and reaction temperature are significant factors. Then the optimum conditions were optimized by response surface analysis, the result showed that the optimum conditions are as follows:catalyst-oil ratio v(IL):v(oil)=0.1, reaction temperature 54.38℃, reaction time 41.12min. Under the optimal reaction conditions, the theory of optimum desulfurization rate is 96.18%, its experimental value is 95.278% tested by experiment which indicated that the model obtained experiments is very reliable.In the end, the performances of FCC gasoline desulfurization using triethylamine hydrochloride salts ionic liquids. the experimental result showed ionic liquid [Et3NH]Cl-FeCl3/CuCl that not only has the effect of desulfurization but also has the ability to reduce the olefin, the rate of desulfurization is 64.64% and the rate of reducing-olefin is 32.59%.