以单体酸为原料制备生物柴油

研究了以单体酸为原料制备生物柴油的方法，反应以对甲苯磺酸为催化剂，单体酸与甲醇进行酯化反应获得脂肪酸甲酯。分别考察了酯化反应条件如甲醇与脂肪酸的摩尔比、反应时间、催化剂浓度以及反应温度对酯化率的影响。通过正交实验得到最佳酯化反应参数：醇酸摩尔比3∶1，反应时间3 h，对甲苯磺酸用量6%，反应温度60 ℃，该条件下单体酸酯化率达98.25%。实验制得的单体酸甲酯生物柴油的主要性能指标符合ASTM质量标准，并与0^#柴油性质接近。

Preparation of biodiesel with monomer acid

An esterification reaction of monomer acid with methanol using p-toluenesulfonic acid as catalyst for the preparation of biodiesel was studied. The process variables that influence the esterification of monomer acid, such as catalyst concentration, molar ratio of methanol to acid, reaction time and reaction temperature, were investigated and optimized. The yield of methyl esters reached to 98.25% under the conditions of reaction temperature of 60 ℃, methanol/acid molar ratio of 3 : 1, and catalyst dosage of 6% for 3 h of reaction. The produced biodiesel was found to exhibit fuel properties within the limits prescribed by the latest American Standards for Testing Material (ASTM) and 0# diesel oil.