甲苯液相无溶剂氧化体系中的相平衡研究

发布时间：2018-05-20 18:14

本文选题：甲苯氧化 + 液液相平衡　；参考：《湖南大学》2015年硕士论文

【摘要】：甲苯氧化反应是重要的工业合成反应,是一条从廉价原料合成高附加值产品的简捷路线。甲苯氧化反应的主要产物有苯甲醇、苯甲醛、苯甲酸,它们都是工业上需求量大、附加值高的产品,广泛应用于医药、食品、染料、化工领域。目前,甲苯氧化法主要包括气相氧化法和液相氧化法。该技术目前较为成熟,但是产物较多,产物的分离与提纯过程也存在一些困难。本文针对甲苯氧化过程中各产物的热力学平衡性质的差异,提出通过物理方法分离甲苯氧化产物的想法,旨在减少甲苯氧化产物分离过程的能耗,同时降低对环境的污染。本文针对甲苯氧化反应的反应液进行相平衡研究,测定相关的热力学基础数据,通过建模的方式检验所测数据的可靠性与可行性。主要内容安排如下:1、使用自制的实验装置进行液液相平衡测定,分别测定了常压下303.2-343.2K时水-苯甲醇-甲苯、水-苯甲醛-甲苯和水-苯甲醇-苯甲醛三组三元物系的液液相平衡数据,并进行了数据的热力学检验。运用NRTL和UNIQUAC活度系数模型对实验所得到的液液相平衡数据进行了模型参数拟合,得到了所测体系的NRTL和UNIQUAC模型的二元相互作用参数。最终根据拟合得出的活度系数模型参数,预测水-苯甲醇-苯甲醛-甲苯四元物系在T=313.2 K时的液液平衡数据,并与实验测得的四元液液相平衡数据进行比较,结果吻合。2、使用自制的实验装置,运用平衡法进行固液相平衡测定,分别测定了常压下苯甲酸在甲苯-苯甲醇、甲苯-苯甲醛、苯甲醇-苯甲醛混合溶剂中的固液相平衡数据,使用NRTL活度系数模型对所有固液平衡数据同时进行模型参数回归,得到了多组NRTL二元相互作用参数。使用得到的模型参数,预测得到苯甲酸在苯甲醇-苯甲醛-甲苯三元体系种的固液平衡数据,与实验数据进行比较,实现了对固液相平衡的预测。3、测定了常压下、温度为303.2-333.2K下,苯甲酸-甲苯-水三元体系、苯甲酸-苯甲醇-水三元体系以及苯甲酸-苯甲醛-水三元体系的固液液相平衡数据。使用NRTL活度系数模型对所有固液液平衡数据同时进行模型参数回归,得到了多组NRTL二元相互作用参数。使用得到的模型参数,预测313.2K下苯甲酸在不同比例的混合溶剂中的固液液平衡数据,并与实验数据进行比较,实现了对固液相平衡的预测。4、甲苯-苯甲醛二元体系以及苯甲醇-苯甲醛二元体系气液相平衡数据进行了归纳总结。并使用NRTL活度系数模型对所有文献数据和以上实验得到的液液、固液和固液液相平衡数据进行了统一了热力学模型关联,得到了一组适合甲苯体系不同相平衡状态关联的NRTL二元相互作用参数。
[Abstract]:Toluene oxidation is an important industrial synthesis reaction, which is a simple route for the synthesis of high value-added products from cheap raw materials. The main products of toluene oxidation are benzyl alcohol, benzaldehyde and benzoic acid, which are the products with high industrial demand and high added value. They are widely used in medicine, food, dyes and chemical industry. At present, toluene oxidation mainly includes gas phase oxidation and liquid phase oxidation. The technology is mature at present, but there are many products, so there are some difficulties in the separation and purification of the products. In view of the difference of thermodynamic equilibrium properties of each product in the process of toluene oxidation, the idea of separating toluene oxidation product by physical method is put forward in this paper, which aims at reducing the energy consumption of the separation process of toluene oxidation product and reducing the pollution to the environment at the same time. In this paper, the phase equilibrium of the reaction liquid for toluene oxidation is studied, the relevant thermodynamic basic data are measured, and the reliability and feasibility of the measured data are verified by modeling. The main contents are as follows: 1. The liquid-liquid equilibrium was determined by using a self-made experimental device. The water-benzyl methanol-toluene was determined at 303.2-343.2K at atmospheric pressure, respectively. The liquid-liquid equilibrium data of three ternary systems of water-benzaldehyde toluene and water-benzyl alcohol benzaldehyde have been tested by thermodynamics. The model parameters of the liquid-liquid equilibrium data obtained from the experiments were fitted with NRTL and UNIQUAC activity coefficient models, and the binary interaction parameters of the NRTL and UNIQUAC models were obtained. Finally, according to the parameters of the fitted activity coefficient model, the liquid-liquid equilibrium data of the water-benzaldehyde toluene quaternary system at T _ (313.2K) were predicted and compared with the four-component liquid-liquid equilibrium data measured experimentally. The results were in good agreement with each other. The solid-liquid equilibrium data of benzoic acid in toluene benzyl alcohol toluene benzaldehyde and benzaldehyde mixtures were determined by using a self-made experimental device and the solid-liquid phase equilibrium method was used to determine the equilibrium data of benzoic acid in toluene benzyl alcohol toluene benzaldehyde and benzaldehyde under normal pressure. Using the NRTL activity coefficient model, all the solid-liquid equilibrium data are regressed simultaneously, and the multigroup NRTL binary interaction parameters are obtained. Using the model parameters, the solid-liquid equilibrium data of benzoic acid in benzol-benzaldehyde toluene ternary system were predicted. Compared with the experimental data, the prediction of solid-liquid equilibrium was realized. The temperature was 303.2-333.2K at atmospheric pressure. The solid-liquid equilibrium data of benzoic acid-toluene-water ternary system, benzoic acid-benzyl methanol-water ternary system and benzoic acid-benzaldehyde water ternary system. The NRTL activity coefficient model is used to regress all the solid-liquid equilibrium data at the same time, and a number of NRTL binary interaction parameters are obtained. The model parameters were used to predict the solid-liquid-liquid equilibrium data of benzoic acid in different proportion of mixed solvents at 313.2K, and the results were compared with the experimental data. The prediction of solid-liquid equilibrium. 4. The gas-liquid equilibrium data of toluene benzaldehyde binary system and benzyl alcohol benzaldehyde binary system were summarized. The NRTL activity coefficient model is used to correlate the liquid-liquid, solid-liquid and solid-liquid-liquid equilibrium data obtained from all the literature data and the experiments above with a unified thermodynamic model. A set of NRTL binary interaction parameters suitable for different phase equilibrium states of toluene system are obtained.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ013.1

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