超声波辐射对酶法制备椰子油脂肪酸甲酯的影响

Effects of ultrasound radiation on coconut fatty acid methyl esters preparation by enzyme

生物柴油作为可再生能源,是环境友好的生物燃料,作为石化柴油的替代品及补充品具有可再生、易于降解、燃烧排放的污染物低、基本无温室效应等特点。本文利用超声辐射强化酯化制备生物柴油具有反应速度快,产率高等优点,探讨了超声辐照对有机相中脂肪酶催化脂肪酸与甲醇酯化反应的促进作用。以蒸馏椰子油脂肪酸、甲醇及Novozym435脂肪酶为主要原料,研究了不同因素及超声辐射对酶法促进油脂脂肪酸甲酯化的影响。对反应条件进行单因素实验,确定了最佳反应工艺参数。经分析初步得出脂肪酶催化甲酯化最佳条件为:酶用量7%,水加入量10%,超声功率250W,反应总时间25min,2mL正己烷/1g脂肪酸,甲醇与椰子油脂肪酸的摩尔比2∶1。在此条件下,脂肪酸甲酯转化率达到90.18%。

Biodiesel,a renewable energy,is environmental friendly.As the substitute and supplement for petroleum,biodiesel has many advantages,such as renewable,easily degradation,low of the combustion emissions and almost no greenhouse effect.In this paper ultrasonic radiation was used in esterifying synthesis biodiesel.The reaction was fast and yield was high.Ultrasonic radiation can assist lipase catalyzed ester synthesis by fatty acid and methanol in organic medium.Effects of different factors and ultrasound radiation on coconut fatty acid methyl esters preparation by enzyme were studied.Coconut fatty acid,ethanol and lipozyme Novozym435 were the major raw material.The single factor is used in optimizing the parameters.The best condition was: enzyme 7%(mass fraction based on oil);water 10%(mass fraction based on oil);ultrasonic power 250W;the total reaction time 25min;n-hexane,2mL/g oil;molar ration of ethanol to coconut fatty acid 2∶ 1.The transesterification yield of 90.18% was obtained under the optimum conditions.