Abstract: Levulinic acid (LA) was prepared from glucose at high temperature and with dilute sulfuric acid. The effects of reaction temperature，sulfuric acid concentration and stirring speed on glucose conversion and LA yield were investigated and optimized. Furthermore，the influence of initial glucose concentration on LA yield under the optimized reaction conditions was analyzed. For the purpose of increasing LA yield under high glucose concentration，two kinds of fed-batch experiments were performed (7%，6% and 5% glucose concentration for three additions；every 3% glucose concentration for six additions). High sulfuric acid concentration，high reaction temperature and high stirring speed were favorable to increasing glucose conversion and levulinic acid generation. High glucose concentration was not conducive to generation of levulinic acid，and the higher the concentration of glucose，the lower the yield of levulinic acid. Yield of levulinic acid increased from 44.3% to 65.9% via fed-batch experiment.

Key words: levulinic acid, glucose, fed-batch, high substrate concentration

摘要： 采用高温下稀硫酸催化葡萄糖的方法制备乙酰丙酸。考察了反应温度、硫酸浓度和搅拌转速对葡萄糖转化率和乙酰丙酸收率的影响，并优化确定了最优反应条件。进一步，分析了最优反应条件下不同葡萄糖初始浓度对乙酰丙酸收率的影响。为了提高高浓度葡萄糖底物反应时乙酰丙酸的收率，采用两种不同的补料方法进行实验：分3次，依次加入7%、6%与5%的葡萄糖；每次均添加3%的葡萄糖，共6次。结果表明：①提高硫酸浓度、反应温度和搅拌速度有利于加快葡萄糖转化和乙酰丙酸生成；②高浓度葡萄糖底物不利于乙酰丙酸的生成，且浓度越高，乙酰丙酸收率越低；③通过补料操作，可使乙酰丙酸收率由 44.3%提高至65.9%。

关键词: 乙酰丙酸, 葡萄糖, 补料法, 高底物浓度