【作者】 张民；

【导师】 姚虎卿； 刘定华；

【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乙二醇生产的主要方法,由于该工艺需要大量的能量用于蒸发产品中85%(wt)以上的水份,造成实际生产中流程长、设备大、能耗高等缺点,直接影响了乙二醇的生产成本;而催化水合法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的研究热点。本文是在前人研究的基础上,对催化水合乙二醇工艺中循环催化剂所需的溶剂进行的相关实验研究。首先按照一定的条件对大量溶剂进行了筛选,找到了一种对催化剂的溶解度大于乙二醇的溶剂―-甘油,然后考察了该溶剂对催化水合反应的影响。第三章和第四章内容分别对溶剂进行了静态性能和动态性能研究,目的是为了进一步考察催化剂在甘油和乙二醇溶剂中的溶解情况。着重从催化剂在溶剂中的溶解度、催化剂与溶剂形成的饱和溶液的粘度和密度等方面进行了比较。此外,本文对NY1 和NY3 两种催化剂在溶剂中的溶解性能也进行了考察。本文的实验研究表明,若用甘油代替乙二醇作为催化水合乙二醇工艺中循环催化剂的溶剂,当催化剂循环液的使用温度控制在120℃以上时,不但能够增大催化剂的溶解量,而且循环液的粘度也没有明显变化,从而可以减少溶液的循环量,节省能耗,进一步完善原催化水合乙二醇工艺。研究内容主要包括: 1) 首先根据该工艺的特性和使用的催化剂的性质,对大量溶剂进行了筛选,研究表明甘油对催化剂的溶解度高于乙二醇;然后通过设计正交实验,探讨了甘油对催化水合反应的影响并得出了有溶剂存在时的最佳反应条件。2) 溶剂的静态性能研究:测定了催化剂与乙二醇、甘油溶剂分别形成的饱和溶液的粘度和密度等方面的物性数据,并作了详细的分析和比较,进而确定了较佳的循环催化剂使用的溶剂以及循环液的温度。3) 溶剂的动态性能研究:通过对动态实验后得到的精馏饱和溶液与相应的直接配制的饱和溶液在溶液的粘度以及催化剂在两种溶液中的质量含量的比较,考察溶剂的静态实验和动态实验之间的区别,为甘油溶剂的进一步工业化应用提供基础。更多还原

【Abstract】 The method of direct hydration with ethylene oxide (EO) is the main way to synthesize ethylene glycol (EG) today. As far as above 85% (wt) water in the products must be evaporated by using massive energy, this has brought about such disadvantages as long process flows, large equipments and enormous waste of energy and affected the cost of production of EG seriously. Recently, the studies of catalytic hydration to synthesize EG have shown good prospects in solving above-mentioned problems and have a virtue of high reaction conversion and selectivity as well, so this method is drawing more and more attention. This paper was based on the former researches about EG and had mainly studied the solvent to recycle the catalyst in the process of synthesis of EG by catalytic hydration. The first step, the experiments were done to determine the solubility of catalyst in many solvents chosen by certain demands and glycerol was found in which the solubility of NY is greater than it in the EG. And then the effects of glycerol on the original reaction were discussed. Secondly, the static and dynamic performances of solvents were respectively studied in chapter 3 and chapter 4, by which the soluble performances of NY in glycerol and EG were deeply compared in the following aspects such as the solubility of NY in the solvents, viscosity and density of the solutions composed of NY and the solvent. Besides, the soluble performances of NY1 and NY3 in the solvents were discussed, too. This paper has shown that if glycerol is used as the solvent to recycle the catalyst in the process of synthesis of ethylene glycol by catalytic hydration and the temperature of circulating solutions is controlled to above 120℃, this not only can raise the soluble quantity of NY but also viscosity of circulating solutions has no distinct variation, so it can reduce the quantity of circulating solution, save the energy and make progress for the original process. The main contents of this paper include the following aspects: 1) At first, a lot of solvents were filtrated which were based on the characteristics of this process and catalysts being used. This research showed that the solubility of NY in glycerol was better than it in EG. And then the effects of glycerol on the original reaction of catalytic hydration were discussed by orthogonal experiments. In the end of chapter 2, the optimal reaction conditions containing glycerol were got. 2) The research about the static performances of the solvents was carried out by following methods. The viscosity and density of the saturated solutions composed of catalyst and solvent were respectively determined and these physical data were analyzed and compared in detail. At last, the better solvent to recycle the catalyst and the temperature of circulate solution were selected in the end of chapter 3. 3) The purpose of the research about the dynamic performances of the solvents was to discuss the differences between the static experiment and the dynamic experiment of the solvents and provide the foundation for the industrialized applications of glycerol. The experimental methods were mainly to compare the viscosities of the solutions and the mass concentrations of catalysts in two saturated solutions, one of which was got by rectifying and the other was accordingly put up by mixing directly. 4) The research about the catalysts of NY1 and NY3 showed that the solubility of NY3 in glycerol and EG were both greater than NY1 and viscosities of the saturated solutions composed of NY3 and the solvents were lower than NY1 under the same temperature. Therefore, if glycerol was used as the solvent to recycle the catalyst in the process of synthesis of EG by catalytic hydration, it was better to choose NY3 as the catalyst.更多还原