【作者】 王冬梅；

【导师】 马沛生；

【作者基本信息】 天津大学 ， 化学工艺， 2007， 硕士

【摘要】 液相扩散在化学、化工及其相关学科的研究中起着重要的作用,其中对扩散系数的实验测定和理论研究更具有普遍的应用价值。另外关于液相扩散系数的实验数据还很缺乏。精对苯二甲酸简称PTA,是聚酯生产的主要原料, PTA生产技术水平的高低直接影响着聚酯工业的发展,要开发PTA生产的新工艺或者改造现有的设备和工艺,就必须有PTA生产过程中相关物系的物性数据。由于技术垄断的原因,所有这些数据都未在公开刊物上发表过,为此,按中国石油化工股份有限公司的要求,本文测定了PTA生产过程中相关体系的扩散系数。论文针对膜池法测定邻、间、对二甲苯与醋酸体系的二元液相扩散系数进行相关的实验基础研究。在前人研究基础上自行设计改建了一套金属膜池法测定二元相互扩散系数的实验装置;采用氯化钾水溶液作为标准物系测定膜池常数,用的乙酸-水溶液体系检验装置的可靠性。测定了298.15-343.15K温度下邻、间、对二甲苯与醋酸二元混合溶液的积分扩散系数,依此计算各自的微分扩散系数,并进行关联。为PTA生产工程设计提供了可靠的部分基础数据。在常压下分别采用日本产Density/Specific Gravity Meter DA-505型U形管振动密度计和乌氏黏度计测定了相应体系的密度和黏度,并对这些数据进行了关联和计算。更多还原

【Abstract】 The liquid diffusion plays an important role in chemistry as well as in chemical engineering and other related fields, among them the experimental measuration and the theory research of diffusion coefficient is of general practical significance. Besides, the experimental data on liquid diffusion coefficient is very scare.Pure terephthalic acid(PTA) is the main raw material in the manufacturing polyesters.The level of the technology in producing PTA affects development of polyester industry. It is necessary to obtain the basic physical properties and thermodynamics properties for developing new process of PTA or renovating old equipment and process. Owing to technological monopoly, all these basic properties about PTA design can’t find in literature. So the diffusion coefficients of the related system in the PTA production process were measured. This project is supported by China Petrochemical Corporation,The work determines the mutual diffusion coefficients of o-xylene, m-xylene, p-xylene with acetic acid by“diaphragm-cell”method. Based on the work studied before, metallic diaphragm-cell to measure mutual diffusion coefficient were prepared. The diaphragm-cell constant were determined by measuring the diffusion coefficient of aqueous solution of aqueous solution of KCl at 298.15K; The reliability of the experimental method was verified by determination for the systems of acetic acid-water solution at 298.15K with which the diffusion coefficients are well know. Metallic diaphragm-cells were employed in measuring the binary integral diffusion coefficients for o-xylene, m-xylene, p-xylene and acetic acid at 298.15-343.15K, Based on the integral diffusion coefficients, their differential diffusion coefficients were calculated and correlated. It is useful and important for engineering and technology design in the PTA production process.Densities and viscosities of the related systems were determined under atmospheric by using Density/Specific Gravity Meter DA-505U vibration tube Ubbelohde suspended-level viscometer. Meanwhile, the calculation to these data were carried on.更多还原