Preparation Of Ethyl Pyruvate By Catalytic Oxidation Of Ethyl Lactate

Ethyl pyruvate is an important organic synthetic intermediate, widely used in biology, medicine, pesticide, spices, food and cosmetics fields etc. This thesis mainly focuses on ethyl pyruvate synthesis from the catalytic oxidation of ethyl lactate and related process development. With cheap ethyl lactate and oxygen in the process for preparation of ethyl pyruvate, the developed process is simple, efficient, environmental-friendly, and has good industrial application prospect.The first chapter is the screening of catalytic oxidation system. Different aspects, such as vanadium compounds, copper salts, catalyst dosage, reaction time, reaction temperature, oxygen pressure, dosage of solvent and solvent of catalytic oxidation system were investigated. The results showed that under conditions of ethyl lactate as substrate, copper composite vanadyl sulfate as the catalyst, molecular oxygen as the oxidant, acetonitrile as solvent, temperature80degrees, reaction time of1.5hours, highly efficient catalytic oxidation of ethyl lactate was achieved, selective conversion of raw material to product has reached99%.The second chapter is the study on synthetic process of ethyl pyruvate. Study on catalytic oxidation process of ethyl lactate when magnified10times. Using the designed gas distributor to enhance oxygen and liquid phase mass transfer effect, the efficient catalytic oxidation of ethyl lactate was achieved at room temperature for6h. Conversion of ethyl lactate was up to97%, and the selectivity of ethyl pyruvate has reached96%.The third chapter is the study on separation and purification of ethyl pyruvate. Due to the similar boiling point of raw materials and products, using conventional distillation method is very hard to get high purity ethyl pyruvate. We studied the separation and purification process of the catalytic reaction system, successively filtered, distilled to remove the solvent acetonitrile, water washing, acid washing, water washing, alkaline washing, and finally water washing, drying, vacuum distillation to obtain the final product. The yield of product was about69%and the purity of the product reached around96%.