响应面法优化无溶剂体系酶法合成己酸乙酯

摘要

目的：探讨无溶剂体系酶法合成己酸乙酯的最佳工艺条件。方法：在单因素试验的基础上,以脂肪酶添加量、底物（己酸/乙醇）物质的量比、反应时间为影响因素,应用二次回归中心组合试验法进行三因素五水平试验,以己酸乙酯产率为评价指标,进行响应面分析。结果：无溶剂体系酶法合成己酸乙酯的最佳工艺条件为脂肪酶添加量0.5%、酸醇物质的量比1：1.3、反应时间12.2h、反应温度30℃,转速150r/min。在此条件下,己酸乙酯产率实际值为81.6%,与预测值相近。结论：采用中心组合试验设计——响应面法对无溶剂体系酶法合成己酸乙酯工艺条件进行优化合理可行。%Objective： To optimize lipase-catalyzed synthesis of ethyl hexanoate in a solvent-free system. Methods： One-factor- at-a-time experiments were cairred out to identify lipase amount, molar ratio of hexanoic acid to ethanol and reaction time as main variables that influence ethyl hexanoate yield for response surface optimization based on a three-valrable, five-level central composite design. Results： The optimum conditions for lipase-catalyzed synthesis of ethyl hexanoate were determined as 0.5% of enzyme amount, 1：1.3 of molar ratio of hexanoic acid to ethanol, 12.2 h of reaction time and 30 ℃ of reaction temperature, and 150 r/min of rotary speed. Under these conditions, the experimental value of ethyl bexanoate yield was 81.6%, which was close to the predicted value （87.7%）. Conclusion： It is feasible to optimize lipase-catalyzed synthesis of ethyl hexanoate in a solvent- free system by response surface methodology.