乙酸乙酯催化萃取精馏新工艺的研究

Synthesis of ethyl acetate by catalytic and extractive distillation new technology

提出了催化萃取精馏合成乙酸乙酯的新工艺,使用化工流程模拟软件Aspen Plus对该工艺进行了模拟和过程优化。得到优化结果:合成塔板数、催化段板数分别为38、14,醋酸和乙醇的进料位置分别为第7、34块板,回流比为1.5,醇酸进料摩尔比为1.15,塔顶乙酸乙酯的质量分数达到93.7%,塔顶无醋酸。搭建了内径30 mm的玻璃实验塔,以强酸型离子交换树脂为催化剂,进行了连续催化萃取精馏合成乙酸乙酯的实验。实验验证了模拟的优化条件,塔顶乙酸乙酯的质量分数达到93.4%,塔顶无醋酸。设计了年产20 000 t乙酸乙酯的工业生产装置,运行效果良好,产品质量分数为99.98%,乙酯的水蒸汽单耗为1.5 t,较传统工艺节能40%以上。

A new process for the synthesis of ethyl acetate by catalytic and extractive distillation is proposed. The process is simulated and optimized by chemical process simulation software Aspen Plus. The optimal conditions are shown as follows： 38 and 14 for the number of synthetic plates and the number of catalytic plates,respectively,7 plate and 34 plate for the feed sites of acetic acid and ethanol,respectively,1. 5 of the reflux ratio,1. 15 of the molar ratio of alkyd feed,93. 7% mass fraction of ethyl acetate and free of acetic acid at the top of the column. A glass experiment column with diameter of 30 mm is built to perform continuous catalytic extraction and distillation of ethyl acetate with strong acid ion exchange resin as catalyst. The optimum conditions of the simulation are verified. The mass fraction of ethyl acetate at the top of the column reaches 93. 4% and there is also no acetic acid at the top of the column. An industrial production plant with an annual output of 20,000 tons of ethyl acetate is designed. The new process is operating well. The purity of product is 99. 98%. The steam consumption of the new technology is 1. 5 t per ton of ethyl acetate. Compared with the traditional technology,the energy consumption can be saved by 40%.