Study On Adsorbent And Adsorptive Distillation Process For Desulfurization Of MTBE

MTBE plays an important role in gasoline upgrating as an excellent gasoline blending agent and the mixing ratios is up to 15%by volume.MTBE still has a great demand even increased in the World including China though the use as a gasoline additive has been prohibited or restricted in the USA and some countries in Europe and Asia.At present,the S content in MTBE product is greater than 50?g/g,or up to hundreds?g/g.However,the regulations in many countries including China claimed that the S content of gasoline should below 10?g/g.Futhermore,MTBE with high purity can be used as chemical solvents or intermediates for organic synthesis.Consequently,the desulfurization of MTBE is imperative.Therefore,the synthesis of adsorbents and adsorptive distillation process for desulfurization of MTBE was studied in this paper.The thesis mainly includes the following research works:1.Ionic liquid[BIm]Cl/CuCl was synthesized by two-step synthesis method with N-butylimidazole,hydrochloric acid and CuCl as raw materials,and characterized by FT-IR?FT-ICR MS and DSC.And then,[BIm]Cl/CuCl was applied as adsorbent in adsorptive distillation desulfurization process of MTBE.The S content in MTBE was reduced to less than 5?g/g.Then,the effect of synthetic raw material ratio,adsorption temperature,stirring speed and water concentration on the desulfurization performance of[BIm]Cl/CuCl was studied,and confirmed the optimal process coditions.The used[BIm]Cl/CuCl can be regenerated by vacuum distillation,and the renewed[BIm]Cl/CuCl can be recycled without the desulfurization efficiency reduced.The desulfurization mechanism of MTBE by[BIm]Cl/CuCl was also proposed.2.CuO/Al₂O₃ as the adsorbent was prepared and characterized by XRD,H₂-TPR,BET and XPS.CuO/Al₂O₃ adsorbent was applied in adsorptive distillation desulfurization process of MTBE.The S content of MTBE was reduced to 2³?g/g.Then,the effect of the capacity of CuO,temperature,space velocity and the S content of MTBE on the desulfurization performance of CuO/Al₂O₃adsorbent was studied,and confirmed the optimal process coditions.The adsorbent can be regenerated by air/N₂ mixtrue and recycled.The desulfurization mechanism of MTBE by CuO/Al₂O₃ adsorbent was also proposed.The desulfurization result of MTBE from another refinery by CuO/Al₂O₃ adsorbent was similarly excellent.The problems of strict demand for equipment materials and liquid waste disposal were solved by replacing ionic liquid[BIm]Cl/CuCl with CuO/Al₂O₃ adsorbent.