Preparation and reaction dynamics on biodiesel made from <emph>Zanthoxylum bungeanum</emph> seed oil and methanol: Fid-Bau Portal

Preparation and reaction dynamics on biodiesel made from Zanthoxylum bungeanum seed oil and methanol

Zhang, Jian / Wang, Xuanjun / Huang, Zhiyong / Han, Qilong / Li, Shuyan / Liu, Hui

Zanthoxylum bungeanum seed oil (ZSO) was the by-product of the zanthoxylum industry, and was a kind of cheap and abundant source in China; it can be of great potential to use as a feedstock for biodiesel production in terms of reducing the producing cost. Biodiesel preparation of ZSO methyl ester by transesterification using potassium hydroxide (KOH) as an alkaline catalyst was studied in this paper. First, the single-factor experiment was practiced, the influence on conversion rate of different factor was studied, such as methanol-to-oil molar ratio, content of catalyst, reaction temperature, and reaction time, etc. Second, the response surface methodology was used to optimize the conditions for ZSO biodiesel production using KOH as a catalyst. A quadratic polynomial equation was obtained for biodiesel conversion by multiple regression analysis and verification experiments confirmed the validity of the predicted model. The optimum combination for transesterification was methanol-to-oil molar ratio 8.5:1, catalyst amount 1.0&percent;, reaction temperature 56 °C, and reaction time 67 min. At this optimum condition, the conversion to biodiesel reached above 98.4&percent;. The relevant error was less than 5&percent; between measurement value of the conversion to biodiesel and expected value. Finally, the reaction kinetics of transesterification was studied. The “Iodine Clock Reaction” principle was used for establishing dynamic model, and corresponding kinetic equation was established. The results showed that the progression of transesterification was grade 1.5, the reaction activation energy was 20.0434 kJ·mol−1, and the pre-exponential factor was 7.8963 dm3/(mol min).