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Biodiesel produced by animal and vegetable oil in ester exchange reaction, not only has the equivalent petroleum diesel combustion, but also has environmental friendly, renewable, and other fine features, is one of the ideal diesel fuel to substitute petroleum. Homogeneous catalysis transesterification to produce biodiesel is the most used technology, but it is difficult to separate catalyst from products and catalyst wastewater cause pollution of the environment and other issues. Alkaline ionic liquids as compared to traditional alkaline catalyst have many advantages, both with high activity of traditional liquid alkali and easy separation of solid base. Therefore, the study of basic ionic liquid catalyzed biodiesel in ester exchange reaction has an important theoretical and practical value.Firstly, article synthesized alkaline ionic liquid [Bmim] OH in tow-step reaction, inspected the reaction molar-ratio, reaction time, reaction temperature, the alkali ratio and alkalization time on the ionic liquid intermediate and basic ionic liquid production-rate effects. The best synthesis conditions of alkaline ionic liquids:reaction temperature is 70℃, reaction time is 20 h, N-methyl imidazole and 1-bromobutane molar-ratio is 1:1.2, the intermediate production-rate can reach 92.64%; alkalization time is 10h, the molar-ratio of intermediate and potassium hydroxide is 1:1.3, the alkaline ionic liquid production-rate can get 54.98%. And then discuss the basic ionic liquid synthesis reaction mechanism. At the same time, characterized and analyzed alkaline ionic liquids with a UV, IR, NMR and other analytical methods, and measured its performance.The soybean oil as raw material, alkaline ionic liquid made in laboratory as catalyst to study the impact factors and optimum conditions of biodiesel. It found that the molar ratio of methanol and oil, ionic liquid dosage, reaction temperature and reaction time affect the biodiesel production-rate. The best technology for basic ionic liquid catalyzed soybean oil on orthogonal access is:the molar-ratio of methanol and soybean is 12:1, catalyst amount of basic ionic liquid is 1.5%, reaction time is 2 h, and reaction temperature is 55℃. Under these conditions, biodiesel production reached 48.1%. The order of the strength of factors is reaction temperature, catalyst amount, reaction time and the molar-ratio of methanol and oil. The study also found that reutilization of ionic liquid is 5 and no significant decrease about catalytic effect.The article also made component analysis and determination of physical and chemical properties for obtained biodiesel. The results show that the main components of biodiesel are methyl oleate and methyl linoleste, and acid value, density and water content and other major indicators are in line with our current production of biodiesel standards. Meanwhile, the paper made the budget and economic benefits of biodiesel and influencing factors about economic benefits.
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