萃取过程的热力学研究(续一)

(2)从 Frank-Thompson 公式出发,在只存在一种电解质的情况下,赵慕愚认为对阴阳离子价态相等的电解质,其单个离子活度系数评算公式可表达如下:     

新的分子热力学模型及其应用(Ⅰ)——一种新的分子径向分布函数表达式的提出及其检验

根据液体的性质、实验现象及统计力学原理,根据总相关函数h(r)与阻尼振动之间存在的相似性,经过分析和数学处理得到了非电解质溶液径向分布函数表达式.应用该式于LJ流体、液态氩以及二元混合溶液体系,计算结果与文验、计算机模拟结果吻合较好.     

A new model for the surface tension of binary and ternary liquid mixtures based on Peng- Robinson equation of state

Based on the surface chemical potential and Peng-Robinson equation of state,a newmodel is proposed to predict and correlate the surface tensions of binary and ternary liquid mix-tures.Using this method,the surface tensions of 73 binary and 8 ternary systems are calculatedwith average relative deviations 1.35% and 3.52% respectively.The proposed model is simple, re-liable and accurate.     

用分子模拟和微扰理论研究超临界NaCl-H2O体系热力学性质

用MC分子模拟方法研究了超临界NaCl-H₂ O体系的径向分布函数和化学势 ,并用考虑硬球、色散和偶极 -偶极作用项的微扰理论公式计算了相同体系的化学势 .结果表明两种方法计算的化学势基本相符     

微扰理论计算氨基酸和糖水溶液的密度

基于微扰理论并借助于统计缔合流体理论的基本思路,建立了氨基酸和糖水溶液密度的状态方程.计算了甘氨酸、丙氨酸、缬氨酸、氨基丁酸和丝氨酸水溶液体系在4个温度下的密度,以及葡萄糖、果糖、半乳糖、树胶醛糖和木糖水溶液体系在5个温度下的密度.此外采用所建立的方程,不引入任何可调参数,直接对氨基酸在尿素水溶液中的密度进行了预测.关联和预测的结果均令人满意.     

基于微扰理论的表面活性剂水溶液表面状态方程

应用微扰理论并借鉴二维气体理论的处理方法,建立了非离子表面活性剂水溶液的表面状态方程。将微扰理论与压力方程相结合,建立了离子表面活性剂水溶液的表面状态方程。运用提出的状态方程,分别对6种烷基聚氧乙烯醚、辛基酚聚氧乙烯醚、十二烷基硫酸钠等表面活性剂水溶液的表面压数据进行了关联,并利用关联所得的参数预测了其他种类的烷基聚氧乙烯醚及辛基酚聚氧乙烯醚和十二烷基硫酸钠水溶液在不同温度下的表面压。关联和预测的精度均较高,结果令人满意。     

高温高压下氯化钠水溶液的热力学(I)——在373—573K及0.1—100MPa条件下NaCI-H_2O体系的热力学性质

本文提出了一个简易的热力学方程式,式中仅包含一个表示长程作用力的静电项,再加上一个表示两粒子间的短程作用项,即可用以计算温度为373—573K,压力为0.1—100MPa、氯化钠浓度为0—10.4mol/kgH_2O的水溶液中氯化钠和水两者的活度系数,计算简便,易于推广使用.     

高温高压下氯化钠水溶液的热力学(Ⅱ)——在823K及100MPa条件下NaCI-H_2O体系的热力学性质

本文将(I)报中提出的简易方程式推广应用到823K和100MPa的NaCl水溶液,NaCl的最高浓度达65.2wt%(三相点时的饱和溶解度)下热力学性质的计算.这些热力学性质包括溶液中水的活度、氯化钠的平均离子活度系数、溶液的Gibbs自由能,计算值与实验值吻合较好.文中列出了不同温度压力下的w和△_8G_2~0/RT值及其变化曲线、和本文提出的参考压力值P_r,为高温高压下电解质水溶液的研究作了初步的探索.     

利用PR状态方程计算临界终点

In the design of chemical processes, such as catalytic cracking of bitumen and heavy oil, the knowledge of phase behavior at the critical endpoint is essential. Based on the PR equation of state, the algorithm developed by Heidemann and Khalil for calculating critical properties was used to compute critical points. An algorithm for determining the equilibrium phase of the critical point using the tangent plane criterion was developed, and was used to calculate the critical endpoints of different mixtures, including non-polar, polar and associating systems. The critical endpoint, representing the type of the phase behavior, was employed to fit the interaction parameter of mixtures in critical state at high pressure. Lines of critical endpoints for ternary mixtures were also determined with the algorithm.     

表面活性剂-油-水体系界面张力的分子热力学模型

An interracial equation of state based on perturbation theory for surfactant-oil-water system has been developed. By comblninE the interracial equation of state with Boudh-Hir and IViansoori‘s model, a molecular thermodynamic model has been proposed. The interracial tension of surfactant-oil-water systems can be calculated from the surface tensions of pure oil and water by this model. The interfacial tension data for sodium dodecyl sulphate-heptane-water system, polyoxyethylene n-octylphenol-heptane-water system and hexadecyl trimethyl ammonium bromide-heptane-water system have been correlated. By using the adjustable parameters obtained, the interfacial tensions of these systems at other temperatures have been predicted. Both the correlated and the predicted values are sstisfactorv.