Study On The Upgrading And Viscosity-reducing Effects Of Ionic Liquids On Heavy Oils

For the fossil energy cannot regenerate, there is an emerging crisis in the modern society now. Heavy oil will be given priority to the oil's exploitation in the future. As a novel kind of catalyst and solvent, ionic liquids (ILs) have many eximious characteristic, and it also accords with the new concept of green chemistry. ILs can be used in the prospective exploitation of oil, especially in the exploitation of the unconventional oil energy sources, such as heave oil, tar sand and oil shale sources.Two types of ILs, Et₃NHCl-AlCl₃ and Et₃NHCl-FeCl₃, have been synthesized; and their compositons have been analyzed. Most of the prescribed ILs' cations are Et₃NH⁺, and only a small amount of Et₂NH₂⁺ have been detected (because of the Et₃NHCl's impurity). Et₃NHCl-AlCl₃ contains many types of anions such as: Al₂Cl₄^-, Al₂Cl₅O^-, Al₂Cl₅(OH)^-, Al₂Cl₇^-, Al₃Cl₆O₂^- and Al₃Cl₉^-, And the types of Et₃NHCl-FeCl₃'s anions include FeCl₄^-. FeCl₅O^-. Fe₂Cl₇^-, Fe₃Cl₁₀^-. By determining and comparing the asphaltene's content of the samples before and after the experiment, the influences of ILs' composition, addition, reaction time and temperature on heavy oil were recorded and analyzed in the the experiments. For Et₃NHCl-AlCl₃, the best condition was that of X_AlCl3=0.35 (mol ratio), ILs' addition is 15% (mass ratio), reactive time 18 hours, and after this experiment, asphaltene's content has been reduced by 45.3%. Moreover, for Et₃NHCl-FeCl₃, the best condition was that of X_FeCl3=0.3, ILs' addition is 15%, reactive time 12 hours, reactive temperature 70℃; and after this experiment, the asphaltene's content has been reduced by 54.7%. We can safely draw a couclusion after determining and comparing the viscosities of the samples before and after the experiment: becauses of the catalysis effects of Et₃NHCl-AlCl₃ and Et₃NHCl-FeCl₃, even under the various conditions, the behavior of the decrease of heave oil's viscosity was exactly accordant with the behavior of the reduce of the samples' asphaltene content; and the reduce reate could achieve 48.9%, 57.1% respectively.Through this study, we can come to the conclusion that, the two types of ILs have a very obvious effect on changing heavy oil's property. Hence, they could be used in the heavy oil's property for reducing the viscosity of heavy oil and changing the property of it as well.