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The world today is facing the dual pressures of energy and the environment, actively looking for environmentally friendly, alternative and renewable energy has become the focus of international attention. Numerous alternative fuels, biodiesel for its superior performance concern. Edible oil as biodiesel production raw materials, not in line with China's basic national conditions, the Government encourages the development of the hilly resources, the development of oil trees, the development of bio-diesel industry. In this paper, the non-food tung oil as raw material, through pre-esterification and esterification two-step biodiesel. Pre-esterification using activated carbon supported sulfuric acid (H 2 SO 4 / AC) and silica-supported sulfuric acid (H 2 SO 4 / SiO 2 ) as a catalyst, the catalytic methanol and feedstock oil esterification reaction of free fatty acids (FFA), thereby reducing the acid value of raw materials; Step 2 In the KOH as a catalyst, the catalytic esterification by lowering the acid value of the processing of tung oil and methanol transesterification reaction of biodiesel. This paper investigated the reaction temperature, reaction time, amount of catalyst and alcohol / FFA molar ratio of the pre-esterification. H 2 SO 4 / AC catalyst optimum conditions: reaction time 1.5h, alcohol / FFA molar 15:1, reaction temperature 90 ° C, the amount of catalyst 3%; 4 / SiO to the H 2 SO 2 catalyst optimum conditions: reaction time 40min, alcohol / FFA molar ratio of 15 : 1, reaction temperature 65 ° C, 0.8% of the amount of catalyst, stirring rate 1000rmp. Under optimum conditions, the two catalysts catalytic esterification reaction conversion rate of more than 92%. Preparation of Biodiesel KOH as catalyst transesterification optimum conditions: reaction time 50min, methanol to oil molar ratio of 6:1, the reaction temperature 70min, 1% of the amount of catalyst. Verification test, the optimal reaction conditions and results of fatty acid methyl ester yield of 97.8%. This article discussed the esterification and transesterification reaction kinetics behavior. The to the the H 2 SO 4 / AC catalyst, through the determination of the type of reaction temperature, the conversion rate of the free fatty acid under the conditions of different molar ratio of alcohol / FFA esterification reaction, in order to determine The dynamics control steps and the kinetic equation parameters to be determined. The results show that created kinetic equation can be used to describe the range of experimental conditions during the esterification reaction; base-catalyzed reaction mechanism, establish simplified kinetic models that transesterification macro-kinetic equation, the results show that in 60 ° C, alcohol-oil molar ratio of 6:1, the esterification reaction is an apparent progression was 3.1, and the rate constant of 2.133 × 10 -3 (mol / L) -2.1 · min -1 , the reaction activation energy Ea = 31.09 kJ · mol -1 , the pre-exponential factor A = 1.958 × 10 5 L · mol -1 · min -1 .
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