稀土复合固体超强酸SO_4^(2-)/ZrO_2-CeO_2催化合成食用香料乳酸乙酯的研究

Study on the Catalytic Synthesis of Flavor Ethyl Lactate by Rare Earth Composite Solid Superacid SO_4^(2-)/ZrO_2-CeO_2

研究了以稀土复合固体超强酸SO_4^(2-)-/ZrO_2-CeO_2作催化剂,乳酸和乙醇为原料合成食用香料乳酸乙酯。通过正交实验考察了影响酯化反应的主要因素,确定的最佳合成条件为:乳酸用量为0.1 mol时,乙醇与乳酸物质的量之比为3.0:1,催化剂用量为乳酸质量的2.5%,回流反应3.0 h,带水剂环已烷20 mL/0.1 mol乳酸条件下,酯化率可达90.3%。且该催化剂具有良好的重复性和再生性。

The synthesis of flavor ethyl lactate with lactic acid and ethanol as reactants and rare earth composite solid superacid SO4^2-/ZrO2-CeO2 as catalyst was studied. The effect of primary factors on esterification was investigated by orthogonal design experiment. The results showed that the optimum reaction conditions were： based on 0. 1mol lactic acid, molar ratio of ethanol to lactic acid was 3.0 ： 1, catalyst amount was 2. 5% of lactic acid mass, water-carrying agent （cyclohexane） was 20mL/0.1mol lactic acid, reaction time was 3. Oh at reflux temperature, the esterification And the catalyst was reused and regenerated. yield was up to 90. 3% under the optimum condition.