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Biodiesel as a green, safe, clean renewable energy, which is of great significance to solve the problems of energy shortage and environmental pollution. However, the conventional homogeneous acid-base catalyst in the catalytic synthesis of biodiesel ester exchange reaction product, the catalyst is difficult to separate, the separation to produce large amounts of wastewater and environmental pollution problems. Environmentally friendly solid base catalyst, and be able to solve the above defects homogeneous catalysts, experimental and theoretical studies of highly active solid base catalytic synthesis of biodiesel is very meaningful. This article four kinds of catalysts were prepared by impregnation, these four catalysts were characterized by analysis, and its in biodiesel synthesis applications. The to K 2 CO 3 and CH 3 COONa as raw materials, the respective concentration of 10%, a 20% aqueous solution, with a solution configured respectively Al 2 O 3 powder the oversaturated impregnated 12h, followed by drying at 105 ° C for 4H, then at 500 ° C and calcined 3H, obtained after the natural cooling to 10% K 2 CO 3 / Al 3 O 3 , 20% K 2 CO 3 / Al 3 O 3 , 10% Na2O / Al 3 O 3 , 20% Na2O / Al 3 O 3 four supported solid base catalyst. In this paper, BET, SEM, IR three kinds of characterization methods of these four kinds of catalyst surface structure and performance analysis, prepared four catalysts catalyst surface structure and good performance, relatively uniform particle size distribution, the active ingredient uniform The distribution of the carrier, the particle surface area, pore volume, pore size desired. These four catalyst the biodiesel synthesis experiments, respectively. Best reaction conditions using orthogonal experiment method and univariate analysis of catalysts, and the combination of yield and energy consumption considering the final the four catalyst preparation biodiesel reaction conditions: 20% K CO 3 / Al 3 O 3 optimal reaction conditions, the molar ratio of 12:1, reaction temperature 60 ℃ reaction time 4h, the amount of catalyst 3%; 10% K is 2 CO 3 / Al 3 O 3 The optimal reaction conditions is the molar ratio of 12:1, reaction temperature 60 ° C, reaction time 3 h, the amount of catalyst 3%; 20% Na2O / the Al 2 O 3 's best reaction conditions is the molar ratio of 12:1, reaction temperature 65 ° C, reaction time 4h, the amount of catalyst 2%; 10% of Na 2 O / Al 3 O 3 optimal reaction conditions is the molar ratio of 9:1, the reaction temperature is 60 ° C, the reaction time 4h, 2% of the amount of catalyst. The experimental results show that the optimum catalyst is 20% Na 2 O / Al 3 O 3 , such a catalyst in the catalytic synthesis of biodiesel the highest yield, biodiesel is 85.4% on the composition and physical and chemical characteristics of biodiesel analysis, and the results show good performance of biodiesel. Finally, the economic feasibility of biodiesel analysis to ensure that the sources of biodiesel feedstock, control the price of raw materials is the key to the large-scale production of biodiesel.
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