蒽和咔唑的溶液结晶热力学及结晶过程研究

发布时间：2018-03-30 06:19

本文选题：蒽　切入点：咔唑　出处：《太原理工大学》2017年硕士论文

【摘要】：蒽和咔唑是来自煤焦油的高附加值工业原料。因其特殊的稠环芳香结构,广泛应用于染(颜)料,医药、农药和光电材料等领域。近年来,由于蒽和咔唑及其衍生物在功能高分子材料、有机发光二极管(OLED)及生物工程等领域的广泛应用,国内外市场对高纯度的蒽和咔唑的需求量逐年增加。溶液结晶法是目前国内主要采用的蒽和咔唑分离方法,研究主要针对蒽和咔唑的分离过程,而对具体的结晶过程研究较少。本研究针对溶液结晶过程中溶剂对蒽和咔唑选择性低和产品质量差等问题,利用改进的液固平衡装置测定了蒽和咔唑在四种溶剂中的溶解度,并利用溶解度模型对数据进行了关联,进而探讨溶剂和杂质对蒽和咔唑结晶过程的影响。得到了粒度均匀,形貌完整的晶体,为蒽和咔唑工业化生产中溶剂的选择和工艺条件的优化提供了理论依据。主要结果如下:1、蒽与咔唑的溶解度测定及关联:利用改进的液固平衡装置分别测定了蒽和咔唑在N,N-二甲基甲酰胺(DMF)、二甲苯(Xylene)、四氯乙烯(TCE)、二乙二醇二甲醚(DGDE)四种溶剂中的溶解度数据,蒽和咔唑的溶解度均随着温度升高而增大。并分别用修正的Apelblat方程、van't Hoff方程和lh模型对实验得到的溶解度进行了关联,回归得到了溶解度方程参数。lh模型对蒽和咔唑的关联效果均优于修正的Apelblat方程。同时,通过van't Hoff得到了不同溶剂中的溶解焓、溶解熵和溶解吉布斯自由能等结晶热力学数据,蒽和咔唑在四种溶剂中的溶解过程均为非自发的吸热过程。2、蒽与咔唑的超溶解度测定及介稳区宽度:测定了蒽与咔唑在DMF、Xylene、TCE、DGDE四种溶剂中的超溶解度,与溶解度曲线比较,得到了蒽与咔唑在溶液结晶过程中的介稳区数据,并讨论了溶剂、降温方式和搅拌速率对介稳区的影响。其中DMF中介稳区的宽度较大,介稳区随着搅拌速率的增大而减小,随着降温速率的增大而增大。3、溶剂及其他因素对蒽与咔唑溶液结晶的影响:分别考察了溶剂种类、搅拌速率、降温方式对蒽和咔唑溶液结晶的影响,采用X射线衍射仪(XRD)、综合热分析仪(DSC)、扫描电镜(SEM)对产品的晶习和形貌进行了表征。最佳的工艺条件为:外循环强制制冷、450 r/min,分别在N,N-二甲基甲酰胺(DMF)和二甲苯(Xylene)中得到了蒽和咔唑的完整晶体。4、蒽和咔唑的溶液共结晶:由于蒽和咔唑结构和物化性质的相似性,在分离精制的过程中互为杂质且极易形成固体溶液。本研究对不同比例的蒽和咔唑进行了共结晶,对得到的液体和固体分别利用气相色谱仪(GC)和XRD、DSC,考察了溶液结晶过程中固体溶液的形成,并讨论了蒽与咔唑溶液结晶中的相互影响。为工业上高纯蒽和咔唑产品的获得提供了基础数据。
[Abstract]:Anthracene and carbazole are high value-added industrial raw materials from coal tar. Because of their special dense ring aromatic structure, they are widely used in dyeing materials, medicine, pesticides and optoelectronic materials. Anthracene, carbazole and its derivatives have been widely used in functional polymer materials, organic light-emitting diodes (OLED) and bioengineering. The demand for high purity anthracene and carbazole is increasing year by year in the domestic and foreign markets. Solution crystallization is the main separation method of anthracene and carbazole in China, and the separation process of anthracene and carbazole is studied. In this study, the solubility of anthracene and carbazole in four solvents was determined by an improved liquid-solid equilibrium device, aiming at the low selectivity of solvent to anthracene and carbazole and poor product quality. The solubility model was used to correlate the data, and the effects of solvent and impurity on the crystallization process of anthracene and carbazole were discussed. The main results are as follows: 1. The solubility of anthracene and carbazole are measured and correlated. The anthracene is determined by an improved liquid-solid equilibrium device. The solubility data of carbazole in four solvents, namely, N-dimethylformamide (DMFN), xylenein, tetrachloroethylene tetrachloride (TCEO) and diethylene glycol dimethyl ether (DGDED). The solubility of anthracene and carbazole increased with the increase of temperature, and the solubility of the experiment was correlated with the modified Apelblat equation and the lh model. The correlation effect of solubility equation parameter. Lh model on anthracene and carbazole is better than that of modified Apelblat equation. At the same time, the thermodynamic data of crystallization such as dissolution enthalpy, solubility entropy and Gibbs free energy in different solvents are obtained by van't Hoff. The dissolution process of anthracene and carbazole in four solvents were all non-spontaneous endothermic process. The supersolubility of anthracene and carbazole and the width of metastable zone were determined. The supersolubility of anthracene and carbazole in DMFX Xyleneum TCEE DGDE was determined and compared with the solubility curve. The metastable region data of anthracene and carbazole in the crystallization process of solution were obtained, and the effects of solvent, cooling mode and stirring rate on the metastable region were discussed. The width of the intermediate stable region of DMF was larger, and the metastable zone decreased with the increase of stirring rate. The effects of solvent and other factors on the crystallization of anthracene and carbazole solution were investigated. The effects of solvent type, stirring rate and cooling mode on the crystallization of anthracene and carbazole solution were investigated. The crystal habit and morphology of the product were characterized by X-ray diffractometer (XRDX), comprehensive thermal analyzer (DSCN) and scanning electron microscope (SEM). The optimum conditions were as follows: forced cooling in outer cycle, 450rm / min, at NN- dimethylformamide (DMF) and xylene (xylene), respectively. The complete crystal of anthracene and carbazole. 4, the solution of anthracene and carbazole were cocrystallized. Due to the similarity of structure and physicochemical properties of anthracene and carbazole, In the process of separation and purification of anthracene and carbazole in different proportions, anthracene and carbazole were cocrystallized. The formation of solid solution in the crystallization process of the solution was investigated by gas chromatograph (GC) and XRDX DSC. The interaction between anthracene and carbazole solution crystallization was discussed, which provided the basic data for obtaining high purity anthracene and carbazole products in industry.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ522.64

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