The esterification of glycerine with free fatty acids using sulfuric, p-toluenesulfonic, and methanesulfonic acids as catalysts is studied in detail analyzing the effect of different variables. These catalysts resulted to be much more active than the heterogeneous catalysts, which require very high temperatures in order to convert high fractions of free fatty acids. The differences in activities among these homogeneous catalysts are explained based on their surface tensions.

This parameter plays a key role in the kinetic behavior, affecting the interface area. An inductive period in the reaction was observed and explained on the basis of the surface tension changes that occur during the reaction due to the formation of monoglycerides, which are compounds that decrease the interfacial tension.

In this reacting system there is a formation of important amount of secondary products with a darkening of the reaction media. In this work these products have been quantified under different reaction conditions, showing the best way of conducting this reaction in order to minimize this loss of yield. Using methanesulfonic acid at a low concentration of 0.35 equiv/L and low temperature (100 °C) complete conversion is obtained with a yield of 95% without darkening of the product.

以硫酸，对甲苯磺酸和甲磺酸为催化剂，对甘油与游离脂肪酸的酯化进行了详细研究，分析了不同变量的影响。这些催化剂比非均相催化剂具有更高的活性，非均相催化剂需要非常高的温度才能转化高比例的游离脂肪酸。基于它们的表面张力解释了这些均相催化剂之间活性的差异。

该参数在动力学行为中起关键作用，影响界面面积。观察到反应的诱导期，并根据在反应过程中由于形成甘油单酸酯而产生的表面张力变化进行了解释，甘油单酸酯是降低界面张力的化合物。

在该反应体系中，随着反应介质的变黑，形成大量的副产物。在这项工作中，已对这些产物在不同的反应条件下进行了定量，显示出进行该反应的最佳方法，以最大程度地减少这种收率的损失。使用低浓度的0.35当量/升的甲磺酸和低温（100°C），可以完成转化，产率为95％，而不会使产品变黑。