顺丁烯二酸酐与邻苯二甲酸二甲酯二元体系在4.00, 8.00和12.00 kPa下的等压气液平衡

采用沸点仪测定了顺丁烯二酸酐和邻苯二甲酸二甲酯二元体系在4.00, 8.00和12.00 kPa下的等压气液平衡数据以及纯DMP组分饱和蒸气压数据, 将实验数据回归得到了纯DMP在417~525 K范围内的Antoine方程. 根据实验平衡温度、 压力和组成数据进一步回归得到NRTL方程参数, 推算出平衡气液相组成, 并利用UNIFAC方程对实验数据进行了预测, 其结果与沸点仪测定结果及NRTL拟合的结果基本相符.     

页岩油馏分的沸点与蒸气压

我们研究了抚顺页岩油馏分的温度与蒸气压的关系,谈现其变化规律基本上与天然石油或纯烃类近似.並且,丛实验结果,求得了计算页岩油馏分蒸气压经验式log P=A-B(T-43)中的常数A、B;制出页岩油的沸点压力对线图,换算误差最大为±2℃.     

顺丁烯二酸酐-癸二酸二丁酯二元体系等温气液平衡

利用改进的沸点仪测定了顺酐-癸二酸二丁酯二元体系在413.15, 433.15和453.15 K下的等温气液平衡数据以及纯癸二酸二丁酯和顺酐的饱和蒸气压数据. 通过与文献值对比, 验证了此方法的可靠性. 同时, 将实验数据回归得到了纯癸二酸二丁酯和顺酐的Antoine常数. 利用NRTL方程进行了气液平衡数据的关联推算, 得到了顺酐-癸二酸二丁酯二元体系的NRTL模型参数. 利用UNIFAC基团贡献法对实验数据进行了预测, 其结果与实验值及运用NRTL方程拟合的结果吻合较好.     

高温高压下煤液化油气液平衡体系的研究

煤液化过程中,反应单元和分离单元是整个液化体系的核心部分,反应器和分离器中各组分在气、液相中的平衡组成确定不仅决定设备的尺寸设计,而且对液化过程中供氢溶剂的选择和反应条件的优化起到关键作用。但由于煤液化油在高温高压下的气、液平衡数据不足,使得反应器内的组成分布无法预测,相关的反应器设计过程仅能凭经验进行。为得到反应条件下的气液平衡数据,研究引入流程模拟软件Aspen Plus,将煤液化油蒸馏得到的窄馏分段与各种气体组分（如H₂、C₂H₆等）共同建立了煤液化油闪蒸过程,得到了高温高压下煤液化油气液平衡体系。利用闪蒸体系计算得到在给定温度、压力情况下,各组分在高温、低温分离器内的气、液两相分布情况,通过改变高温分离器的温度和压力,分析了高温分离器内相平衡常数随温度（623.15K~723.15K）、压力（10MPa~21MPa）变化的规律。为进一步归纳适用于煤液化油的气液平衡方程,以高温分离器数据为基础,对推导建立的高压下烃类相平衡方程中的参数进行回归,得到高温高压下,适用于神华煤液化油并具有物理意义的二元（T,p）气液相平衡常数方程。     

碳氢燃料的蒸发焓与1H NMR结构参数

用500MHz超导核磁共振仪测定了36个碳氢燃料油的^1HNMR谱，获得各类氢的相对含量。假设碳氢燃料由直链烷烃和直链烷基苯两种模型化合物构成，^1HNMR结果和相对分子质量计算了相应的基团组成数。采用斜式沸点计测定燃料在不同温度下的泡点蒸气压，根据Clausius-Clapeyron方程计算了燃料的蒸发焓和蒸发熵。以基团贡献法为桥梁，把微观的^HNMR结构信息与宏观的蒸发性质联系起来，给出一个预测碳氢燃料蒸发焓的基团贡献表达式，检验结果表明偏差为 5.4％- -5.9％（平均2.1％）。用此表达式预测了17个纯烃和石油馏分的蒸发焓，偏差为 8.5％- -10.1％（平均3.3％）。     

外压与凝聚态物质饱和蒸气压关系的讨论

应用外压与饱和蒸气压的关系公式,推导了范霍夫公式和开尔文公式。温度一定时,平液面的饱和蒸气压只会大于或等于真空密闭系统中纯物质气液平衡时的饱和蒸气压。毛细管的凹液面还会出现比平液面的饱和蒸气压小的情况。该关系公式称为"凝聚相表面的压力与饱和蒸气压的关系公式"更为合理。     

共沸点存在的充分条件

以纯液体蒸气压和亨利系数为出发点,讨论了二组分气液相图存在共沸点的充分条件。结合纯液体蒸气压和亨利系数的物理意义,对共沸点存在的条件进行了说明。     

多次相平衡—气相色谱法测定分配常数

测定分配常数通常需要同时分别测定组分在气液两相中的浓度,一般比较麻烦。本文参考文献工作,应用多次相平衡-气相色谱法,只需分析气相组成就可测得组分在气液两相中的分配常数。同时可根据直线外推的截距值经检测器响应因子校正,求得组分在水相中的原始浓度。     

双液系气液平衡相图实验的研究

二组分完全互溶的双液系的气液平衡相图实验是物理化学实验的基本内容之一,通常是用沸点仪在常压条件下测定双液系在不同组成时的沸点和气、液两相呈平衡时的组成,从而作出沸点-组成相图。外界压力不同时,同一双液系的相图也不尽相同,所以恒沸点和恒沸混合物组成与外压有关。因此,通常情况下,用标准数据去衡量学生实验所得的恒沸点和恒沸混合物的数据就不够精确。本文是用自制的简易恒压沸点仪,在不同的压力下,对丙酮-氯仿和异丙醇-环己烷体系的恒沸点,恒沸混合物组成进行了研     

测定液体饱和蒸气压的一种沸点计

纯组分的饱和蒸气压是物性的重要参数。化工生产中,蒸馏、吸收等过程的设计、开发或革新均离不开相平衡,因此饱和蒸气压是化工分离过程中不可缺少的热力学基础数据。这些数据在文献中虽能查找,但对于一些新材料、新物质或由于所用物料纯度等影响,以及所要求的温度、压力范围不同,都需要进行实验测定。欲测得准确的饱和蒸气压数据,必须使所测温度、     

Isobars of the boiling temperature and isotherms of excess thermodynamic functions of isobutanol-alkyl ketone solutions

The boiling temperatures for solutions of five binary systems are measured via ebulliometry in the pressure range of 5.333–101.3 kPa. The isotherms constructed for the pressure of saturated vapor serve as the base for computing the compositions of equilibrium vapor phases of the systems. The excess Gibbs energies, enthalpies, and entropies of solutions are computed from the data on liquid-vapor equilibrium. The laws of changes in the phase equilibria and thermodynamic properties of solutions are determined depending on the composition and temperature of the systems. The vapor-liquid equilibrium of the systems is described by Wilson and NRTL equations.     

氯仿,乙醇,苯有关二元体系加压相平衡研究

氯仿、乙醇、苯有关二元体系加压相平衡研究马忠明，陈庚华，王琦，严新焕，韩世钧，余淑娴（浙江大学化学系，杭州，３１００２７）（江西大学化学系）关键词加压汽液平衡，醇烃体系，氯仿，乙醇，苯醇是极性分子，烃是非极性或弱极性分子，醇与醇、烃与烃分子及醇与烃分...     

Isobaric Phase Equilibria in the Binary Systems Ethyl 1,1-Dimethylethyl Ether + 1-hexene and + Cyclohexene at 94.00 kPa

Abstract

Consistent vapor-liquid equilibrium has been determined for the binary systems 1-hexene + ethyl 1,1-dimethylethyl ether (ETBE) and ethyl 1,1-dimethylethyl ether + cyclohexene at 94.00 kPa. The two systems present slight positive deviations from ideal behavior, can be considered to behave like regular solutions and do not present azeotropic behavior. Pure component vapor pressures are also reported for 1-hexene and cyclohexene. The phase equilibrium of the systems was correlated well by the Wilson, UNIQUAC, and NRTL models and reasonably predicted by the UNIFAC group contribution method. The boiling points of the binary systems were correlated with the Wisniak-Tamir equation.     

Vapor–liquid equilibria and density measurement for binary mixtures of o-xylene + NMF, m-xylene + NMF and p-xylene + NMF at 333.15 K, 343.15 K and 353.15 K from 0 kPa to 101.3 kPa

Isothermal vapor–liquid equilibria at 333.15 K, 343.15 K and 353.15 K for three binary mixtures of o-xylene, m-xylene and p-xylene individually mixed with N-methylformamide (NMF), have been obtained at pressures ranged from 0 kPa to 101.3 kPa over the whole composition range. The Wilson, NRTL and UNIQUAC activity coefficient models have been employed to correlate experimental pressures and liquid mole fractions. The non-ideal behavior of the vapor phase has been considered by using the Peng–Robinson equation of state in calculating the vapor mole fraction. Liquid and vapor densities were measured by using two vibrating tube densitometers. The excess molar volumes of the liquid phase were also determined. Three systems of o-xylene + NMF, m-xylene + NMF and p-xylene + NMF mixtures present large positive deviations from the ideal solution and belong to endothermic mixings because their excess Gibbs energies are positive. Temperature dependent intermolecular parameters in the NRTL model correlation were finally obtained in this study.     

Isobaric Vapor-Liquid Equilibria and Densities for the System Ethyl 1,1-Dimethylethyl Ether + 2-Propanol

Vapor-liquid equilibrium (VLE) data at 50, 75, and 94 kPa have been determined for the binary system ethyl 1,1-dimethylethyl ether + 2-propanol, in the temperature range 323-344 K. The measurements were made in an equilibrium still with circulation of both the vapor and liquid phases. Excess volumes have been also determined from density measurements at 298.15 K. The system exhibits positive deviation from ideal behavior and azeotropic behavior in the range of experimental pressures. The excess volume of the system is negative over the whole mole fraction range. The activity coefficients and boiling points of the solutions were well correlated with the mole fraction by the Wohl, Wilson, UNIQUAC, NRTL equations and predicted by the UNIFAC group contribution method. Excess volume data were correlated using the Redlich-Kister expansion.     

Vapor–liquid equilibria of the binary mixtures formed by nitromethane with five alkyl alkanoates at 101.3 kPa

Vapor–liquid equilibria were measured at 101.3 kPa, in a range of temperatures from 350.28 to 374.69 K, for five binary mixtures formed by nitromethane with ethyl acetate, propyl acetate, isopropyl acetate, methyl propionate, and ethyl propionate. Calculations of nonideality of the vapor phase were made with Soave–Redlich–Kwong equation of state. Thermodynamic consistency of data was tested via Herington analysis. Two systems show minimum boiling azeotropes. The experimental VLE data were reduced and binary parameters for four liquid models, such as van Laar, Wilson, NRTL and UNIQUAC, were fitted. A comparison of model performances was made by using the criterion of average absolute deviations in boiling point and in vapor-phase composition.     

Isothermal vapor–liquid equilibria for binary mixtures of benzene, toluene, m-xylene, and N-methylformamide at 333.15 K and 353.15 K

Isothermal vapor–liquid equilibrium (VLE) at 333.15 K and 353.15 K for four binary mixtures of benzene + toluene, benzene + N-methylformamide, toluene + m-xylene and toluene + N-methylformamide have been obtained at pressures ranged from 0 kPa to 101.3 kPa. The NRTL, UNIQUAC and Wilson activity coefficient models have been employed to correlate experimental pressures and liquid mole fractions. The non-ideal behavior of the vapor phase has been considered by using the Soave–Redlich–Kwong equation of state in calculating the vapor mole fraction. Liquid and vapor densities were also measured by using two vibrating tube densitometers. The P–x–y diagram and the activity coefficient indicate that two mixtures of benzene + toluene and toluene + m-xylene were close to the ideal solution. However, two mixtures containing N-methylformamide present a large positive deviation from the ideal solution. The excess Gibbs energy in the benzene + toluene mixture is negative indicates that it is an exothermic system.