【作者】 刘鑫；

【导师】 夏清；

【作者基本信息】 天津大学 ， 化学工程， 2020， 硕士

【摘要】 2,5-二甲氧基-4-氯苯胺(缩写CDMA)是一种制备红色和黄色偶氮类有机染料的重要中间体。CDMA的产物中通常存在的未反应完全的2,5-二甲氧基-4-氯硝基苯(缩写CDMB)以及脱卤产物2,5-二甲氧基苯胺(缩写DMAn),极大地降低了下游产品色酚AS-LC和色酚AS-IRG的质量。本研究根据两种色酚的不同生产要求,分类讨论适合用做提纯CDMA的重结晶的有机溶剂,并提出具体的优化思路。根据相似相溶原理,本文采用动态法测定常压下275-340 K三种溶质在乙二醇甲醚、乙二醇乙醚、丙二醇甲醚、二乙二醇、二乙二醇单甲醚、二乙二醇二甲醚、二乙二醇乙醚、苯甲醚、二乙二醇二乙醚、乙二醇正丙醚、苯甲醇和苯乙酮中的溶解度。通过Wilson、NRTL、Apelblat和λh模型进行关联。利用单纯形法的多次优化,计算得到模型参数和均方根偏差。Wilson和NRTL模型的准确性更高,均方根偏差分别为0-1.35 K和0-1.83 K。结果显示,三种溶质的溶解度均随温度的升高而增大,温度对DMAn的溶解度变化影响较大,而对CDMB的影响较小。从溶剂的分子结构的角度分析,碳链加长不利于溶质的溶解,醚基或者羰基的引入有利于溶质的溶解。对于生产色酚AS-LC,苯乙酮更加适合作为提纯溶剂,在295-340 K这一范围内,CDMA的溶解度恰好为CDMB的2倍,并且两种溶质的溶解度随温度的升高成规律的线性变化。对于生产色酚AS-IRG,二乙二醇适合作提纯溶剂,温度低于305 K时,DMAn基本不溶,当温度高于305 K时,DMAn溶解度迅速增大。这一特点更有利于分离DMAn以及后续生产。更多还原

【Abstract】 4-chloro-2,5-dimethoxyaniline(CDMA,CAS No.6358-64-1)is an important intermediate for the preparation of yellow and red azo organic pigments.The remaining4-chloro-2,5-dimethoxynitrobenzene(CDMB CAS No.6940-53-0)which does not react and the dehalogenation production 2,5-dimethoxyaniline(DMAn CAS No.102-56-7)contained in the system would lower the quality of AS-IRL and AS-LC.We found suitable organic solvents which can purify CDMA by recrystallization respectively according to different conditions,and then optimized the production process of AS-LC and AS-IRG.We chose to study the solubility in 12 organic solvents(2-methoxyethanol,2-ethoxyethanol,1-methoxy-2-propanol,diethylene glycol,2-(2-methoxyethoxy)ethanol,diethylene glycol dimethyl ether,diethylene glycol monoethyl ether,anisole,2-ethoxyethyl ether,ethylene glycol monopropyl ether,benzyl alcohol and acetophenone)based on the principle of the dissolution in the similar material structure.In this work,the solubility data had been measured by a dynamic method over the temperature range from 275 to 340 K at atmosphere pressure.The experimental data were correlated with the Wilson,the NRTL,the modified Apelblat and the λh models,which have been successfully used to describe the solid-liquid equilibrium(SLE).The interaction parameters of the models and the root-mean-square-devation(RMSD)were obtained using the Nelder Mead Simplex Method through Matlab.The Wilson and the NRTL models have higher accuracy for the RMSD of them are 0-1.35 K and 0-1.83 K respectively.Experimental results show that in all the systems,the solubility of CDMB,CDMA and DMAn increase with temperature.The solubility of DMAn is strongly dependent on temperature,whereas CDMB is weakly dependent.As for the molecular structure of the solvent,in general,increasing the length of the carbon chain can reduce the solubility while adding the ether group or the carbonyl can increase the solubility of three solutes.To produce AS-LC,acetophenone was suggested to be used as recrystallization solvent.From 295 K to 340 K in acetophenone,CDMA is twice as soluble as CDMB,and the solubility both vary linearly as the temperature increase.As for AS-IRG,diethylene glycol was preferred.When the temperature is lower than 305 K,DMAn is almost insoluble,but when the temperature is higher than 305 K,the solubility of DMAn increase rapidly.It is easier to remain DMAn in the solvent and to carry out the following process.更多还原