Preparation method of fatty acid monoethanolamide

The invention relates to a preparation method of fatty acid monoethanolamide, which has the advantages of reduced side reaction, high grease conversion rate and low product ester value, and is characterized in that a premixing step is added before the reaction, and a small amount of glycerol is added at the early stage of the reaction to be used as a protecting group of hydroxyl in the fatty acid monoethanolamide; and the formation of byproducts such as amine ester and amide ester in the reaction process is inhibited, so that the ester value of the product is lower, the CMEA ester value is below 6mgKOH/g, the amine value is below 4mgKOH/g, the purity of the product is improved, and the water solubility of the product is improved. 本发明涉及一种副反应减少、油脂转化率高、产品酯值低的脂肪酸单乙醇酰胺的制备方法，本发明在反应前加了一个预混合步骤，主要是通过在反应前期加入少量的甘油，作为脂肪酸单乙醇酰胺中羟基的保护基，抑制反应过程中副产物胺酯、酰胺酯的形成，使产品的酯值更低，CMEA酯值均在6mgKOH/g以下，胺值在4mgKOH/g以下，产品纯度提高，产品水溶性提高。