Abstract: Macrokinetics of transesterification of castor oil with methanol was studied in the presence of NaHSO₄·H₂O catalyst using method of excessive concentration. The relationship between castor oil conversion and reaction time and the relationship between methanol conversion and reaction time were investigated at different temperature.Methyl ester contents in the system at different reaction time were determined by high-performance liquid chromatography.The experimental data were dealt with linear regression method. The results show that reaction order is 1.5 for castor oil and is 0.5 for methanol,and that under the conditions of reaction temperature 303,313,323,333 K,mass ratio of catalyst to oil 5%,agitation speed 600 r/min, the apparent rate constant is 0.003 934,0.005 271,0.006 656,and 0.008 237 dm³/(mol·min) ,respectively, the apparent activation energy is 20.627 kJ/mol and the apparent frequency factor is 14.2806 dm³/(mol·min).The results predicted by the kinetic equition are in good agreement with the experimental results.

Key words:

摘要： 采用过量浓度法对一水硫酸氢钠催化蓖麻油与甲醇酯交换反应宏观动力学进行了研究。考察了不同温度下蓖麻油转化率和时间的关系以及甲醇转化率和时间的关系。用高效液相色谱仪测定了不同反应时刻系统的甲酯含量。用线性回归方法处理实验数据得出:蓖麻油分级数为1.5, 甲醇分级数为0.5 ;当反应温度为303、313、 323 、333 K , 催化剂加入量为油质量的5 %, 搅拌速率为600 r/ min 时, 表观速率常数分别为:0.003 934、0.005 271、 0.006 656、0.008 237 dm3/(mol · min), 表观活化能为20 .627 kJ/ mol, 表观频率因子为14.280 6 dm3/(mo l· min)。动力学方程的预测结果和实验结果吻合较好。

关键词: 一水硫酸氢钠 , 催化 , 蓖麻油 , 生物柴油 , 动力学