废食用油脂固定床酶法合成生物柴油研究

Preparation of biodiesel from waste cooking oil in fixed bed reactor by immobilized lipase

利用废食用油脂合成生物柴油,既能够实现废弃物的清洁利用,又能提供可再生的绿色能源。采用固定化假丝酵母脂肪酶为催化剂,在三级固定床反应器内,采用分级流加甲醇的方式,每级醇油摩尔比为1∶1,探讨了酶质量分数、溶剂质量分数、水质量分数、温度、反应液流速等与产物中甲酯质量分数的关系。实验结果表明,当油中酶、溶剂、水的质量分数分别为25%,15%,10%,反应液流速为1.2 mL/min,温度为45℃时,产物中甲酯质量分数达到最大值91.08%,其中油酸甲酯质量分数最高。产品经过精制后,理化性质符合美国和德国生物柴油标准,绝大多数指标优于我国0#柴油。

Synthesis of biodiesel catalyzed by immobilized lipase from waste cooking oil （WCO） is an effective method to reuse the waste cleanly and produce the renewable energy. The transesterification was catalyzed in a three-step fixed bed reactor and the mole ratio of acid oil to methanol was 1 ：1 in each step. The effects of enzyme mass fraction, solvent mass fraction, water mass fraction, temperature and flow velocity of reactant on the reaction were analyzed. The result indicates that under the optimal conditions of the mass fraction of 25% immobilized lipase ,15% hexane and 10% water in acid oil, the flow velocity of reactant 1.2 mL/min and reaction temperature 45℃, the fat acid methyl ester （FAME） mass fraction 91.08% in the product can be obtained and methyl oleate is the most component of biodiesel. Most of chemical and physical properties of biodiesel meet the American and German biodiesel standards and exceed Chinese standard of 0^# diesel.