酶法与碱法联合催化高酸值鱼油乙酯化的研究

Ethyl esterification of high-acid fish oil catalyzed by combination of enzyme and alkali

以高酸值鱼油为原料,采用酶法与碱法联合催化鱼油进行乙酯化反应。首先以脂肪酶为催化剂,催化鱼油与乙醇酯化反应降低原料酸值,得到优化的反应条件为:底物鱼油与无水乙醇的摩尔比为1∶1,脂肪酶Novozym 435加量为鱼油质量的2%,反应温度45℃,恒温振荡器转速为180r/m in,反应时间6 h。在此优化条件下,鱼油酸值(KOH)从10.20 mg/g降至0.67 mg/g,再以氢氧化钠为碱催化剂,催化鱼油进行进一步乙酯化反应,反应1.5 h后乙酯产率达到96.5%。

The ethyl esterification of fish oil with high acid value was catalyzed by combination of enzyme and alkali. First, lipase was used to catalyze the reaction of fish oil and ethanol to decrease the acid value of fish oil, and the optimal conditions were obtained as follows ： molar ratio of fish oil to anhydrous ethanol 1： 1, the amount of lipase Novozym 435 2% （ based on the mass of fish oil）, reaction temperature 45 ~（2, oscillator speed 180 r/min, reaction time 6 h. Under the optimal conditions, the acid value of fish oil fell to 0.67 mgKOH/g from 10.20 mgKOH/g. And then sodium hydroxide was used as the alkaline catalyst for the further ethyl esterification, the yield of ethyl esters was 96.5% after reaction for 1.5 h.