【作者】 王艳丽；

【导师】 马正飞； 戴厚良；

【作者基本信息】 南京工业大学 ， 化学工程， 2005， 硕士

【摘要】 环氧乙烷直接水合法是当今工业生产乙二醇的主要方法,但该工艺为提高产品乙二醇的选择性,加大了原料中水的含量,这导致装置上必须设置多效蒸发单元,增加了工艺流程的复杂性和设备投资,直接影响了乙二醇的生产成本。而催化水合工艺在解决上述问题方面显示了很好的前景,并保证了该反应的高转化率与高选择性,因而成为合成乙二醇研究的热点。本文针对NY 催化剂均相催化水合合成乙二醇体系的特点,设计动力学实验,对该体系的反应动力学特性进行深入研究,测定不同操作条件下的反应速率和活化能,并根据实验数据建立反应动力学模型,提出反应机理,探讨影响反应选择性的主要原因。同时根据混合整数非线性规划(MINLP)的方法,建立年产200 吨的均相催化水合法合成乙二醇反应精馏塔计算模型,并使用GAMS(the General Algebraic Modeling System)软件对其进行优化计算。通过本文的研究,掌握均相催化水合法合成乙二醇反应的规律,得到所需的动力学数据,可为该工艺过程的开发和工业反应器的设计提供理论依据,同时对改进和完善该催化剂的性能也具有非常积极的意义。本文主要结果包括: 1. 考察不同反应气氛、温度、水比和催化剂浓度下均相催化水合法合成乙二醇的反应动力学行为,测定所需要的动力学数据。动力学实验研究结果表明:在NY 催化剂存在下,均相催化水合法合成乙二醇的反应是相对于环氧乙烷及催化剂浓度的一级反应。2. 研究并验证不同反应气氛下均相催化水合法合成乙二醇的反应机理,根据反应机理建立反应动力学模型并回归模型中的参数,结果表明:提出的反应机理与实验现象相符合,模型的计算值和实验值一致性良好。3. 探讨不同反应气氛对均相催化水合过程造成的影响,并从反应机理的角度解释了在二氧化碳充压条件下均相催化水合法合成乙二醇反应的选择性高于氮气条件下反应选择性的原因。4. 使用混合整数非线性规划的方法建立年产200 吨的均相催化水合法合成乙二醇的反应精馏塔计算模型, 使用GBD ( General Bender’s更多还原

【Abstract】 Now, the method of direct hydration from Ethylene oxide(EO) is one of the ways to produce Ethylene glycol(EG). In order to get the high selectivity, too much water is added during the reaction. So a triple-effect evaporator is needed in the process which greatly increases the investment of equipments and the energy cost for the EG production. Recently, the studies of catalytic hydration show a good prospect in solving above-mentioned problems, and have a virtue of good conversion and selectivity as well, so much attention is put on the exploratory researches in the field. In this thesis, The kinetics of catalytic hydration from EO was studied in detail. We carried out experiments according to the characteristic of the system of catalytic hydration from EO. The rate constants and the activity energy were obtained. The mechanism of the reaction was proposed according to the experimental results, and the kinetic equation was established with the parameters estimated. The reasons which made the differences of selectivity in the atmosphere of N2 and CO2 was also discussed. In the meantime, A synthesis of non-equilibrium reactive distillation processes by mixed integer nonlinear programming(MINLP) optimization was calculated. The rules of the kinetics of catalytic hydration from EO were known by the study. And the data of the kinetics were obtained. These data would do a favor for a development of process flows and the design of reactor. It could also give some help for improving on the characters of catalyst. The studies of this thesis mainly included the following aspects: 1. The kinetics of catalytic hydration from EO were studied at the different atmosphere, temperature, concentrations of the catalyst and the different quality ratio of water and EO. The data of the kinetics were obtained from the experiment. According to the results, the kinetics equation was first order with respect to the concentrations of EO and the concentrations of catalyst. 2. The mechanism of the reaction was proposed and proved according to the experimental results. The kinetic equation was established and the parameters were also estimated. It was concluded that the mechanism of the reaction could interpret the experiments. The values of the experiment had a good fit with the calculation values. 3. The reason which made the differences of selectivity in the different atmosphere was discussed. And the results that the selectivity in CO2 was higher than it in N2 were explained according to the mechanism of the reaction. 4. A MINLP model is presented for synthesizing reactive distillation columns. The General Bender’s Decomposition solution procedure is used for mixed integer nonlinear programming and the solution algorithm was implemented in GAMS(the General Algebraic Modeling System). The optimal column with infinite reflux ratio contains eight trays and has a total annualized cost of 2.02×106$/a. The solution composed of water and catalyst is fed to seventh tray, and the ethylene oxide if fed to the third tray. The column diameter is 1.18m.更多还原