可膨胀石墨对动物油脂的催化酯交换反应研究

STUDY ON THE CATALYSIS OF EXPANDABLE GRAPHITE IN TRANSESTERIFICATION REACTION OF ANIMAL OIL

本研究以动物油为原料,可膨胀石墨作催化剂,通过与乙醇的酯交换反应制备了生物柴油。正交试验考察了反应时间、油-醇质量比和催化剂加入量等因素对生物柴油产率的影响。实验确定酯交换反应最佳反应条件为:油醇质量比1∶1.5、催化剂用量为油重的20%、反应时间12h、反应温度控制为80℃。极差分析结果表明:反应时间对生物柴油产率的影响最大,其次为催化剂用量及油醇比例。可膨胀石墨的膨胀容积越大,酯交换反应产率越高。加入表面活性剂可以加快反应速度,提高生物柴油产率。加入壬基酚聚氧乙烯醚(OP-4)后,最佳条件下生物柴油产率为0.935g/g。可膨胀石墨可以作为动物油脂与乙醇酯交换反应的催化剂。

Biodiese oil was prepared by transesterification of animal oil with ethanol under the catalysis of expandable graphite. We studied the influence of mass ratio of ethanol to animal oil ,amount of catalyst ,and reaction time on yield of biodiesel oil, respectively. The optimum reaction conditions were investigated through orthogonal experiments,and they were determined as following ：mass ratio of ethanol to oil was 1 ： 1.5,the dosage of catalyst was 20 g expandable graphite versus 100 g animal oil,and reaction time of 12 h with a reaction temperature of 80℃. Analysis of these results showed that reaction time was the most important influencing factor on yield of biodiesel oil and the effect of the dosage of catalyst and the mass ratio of ethanol to animal oil on yield of biodiesel oil was minor. The yield increased with the increasing of the expansion volume of expandable graphite. With the adding of surface active agent nonyl phenol polyoxyethylene ether（OP-4）,the yield of biodiesel oil was improved to 0. 935 g/g under the mentioned optimum condition. Expandable graphite can be used as an effective catalyst in the transesterification of animal oil with ethanol.