丙烷-乙醇-水体系相平衡研究

提出了改进的DDLC-MH(81)状态方程,用于丙烷-乙醇-水体系二元汽液平衡数据的关联计算,其模型参数与温度有良好的线性关系.并用汽相循环法测定了该体系在不同温度下的二元及三元VLE数据,结果与模型的推算值取得良好的一致.并用模型预测了超临界丙烷条件下的三元相平衡数据.结果表明,在液相乙醇浓度高于0.2的情况下,超临界丙烷比超临界二氧化碳有更高的乙醇溶解度和选择性.     

2,2-二甲基丁烷+乙醇、+正丙醇二元体系常压汽液平衡的测定

使用自行设计的汽液平衡釜测定了常压下2,2-二甲基丁烷+乙醇和2,2-二甲基丁烷+正丙醇二元体系的汽液平衡数据,所得到的汽液平衡数据通过了Herrington面积法热力学一致性检验。实验数据用NRTL方程进行关联,采用关联得到的模型参数计算相应的汽相组成,并与实验值比较。汽相组成的平均偏差小于0.02,这说明NRTL模型适用于所研究的二元体系。     

Prediction of partial molal volumes of normal fluid mixtures

Partial molal volumes of normal fluid mixtures in the liquid state were evaluated by means of a modified Redlich-Kwong equation of state. Molal volumes and vapor pressures of pure saturated liquids were used for evaluating the two parameters of the equation. These parameters were treated as temperature dependent. Partial molal volumes of six binary systems were satisfactorily predicted in this investigation. Satisfactory compressibility factors for pure liquids at high pressures were also obtained by the proposed method.     

Isothermal vapor-liquid equilibria for the binary systems of ethylene glycol monopropyl ether with 2,2-dimethylbutane and 2,3-dimethylbutane

Isothermal vapor liquid equilibria for the binary system of ethylene glycol monopropyl ether with 2,2-dimehylbutane and 2,3-dimethylbutane were measured in a circulating water bath at 303.15, 318.15, and 333.15 K. The apparatus was in-house designed and manufactured. Consistency testing of the apparatus was done by comparing the measured vapor pressures to the calculated vapor pressures from the Antoine equation. The measured systems were correlated with a Peng-Robinson equation of state (PR) combined with Wong-Sandler mixing rule for the vapor phase, and NRTL, UNIQUAC, and Wilson activity coefficient models for the liquid phase. All the measured systems showed good agreement with the correlation results.     

3-羟基丁酸乙酯-巴豆酸乙酯-乙醇三元体系等压汽液平衡

在汽液双循环玻璃平衡釜中测定3-羟基丁酸乙酯、巴豆酸乙酯、乙醇的二元及三元体系的等压汽液平衡数据,用积分法对其进行了热力学一致性检验.回归实验数据得到3-羟基丁酸乙酯和巴豆酸乙酯的Antoine方程参数.用Wilson活度系数方程对实验数据进行了关联,取得了较好的结果.     

Measurement and modelization of VLE of binary mixtures of propyl acetate,butyl acetate or isobutyl acetate with methanol at pressure of 0.6 MPa

The vapor–liquid equilibrium of binary mixtures of propyl acetate,butyl acetate and isobutyl acetate with methanol has been determined at a constant pressure of 0.6 MPa.Results have been modeled with the Peng–Robinson equation,a traditional cubic equation of state widely employed in chemical industries,as well as with the perturbed-chain statistical associating fluid PC-SAFT theory of Gross–Sadowski.By correlation of the binary interaction parameters of these equations,the measured vapor–liquid equilibrium data can be accurately predicted.Thus,this work shows that these models are able to represent the experimental data for systems with associating compounds via hydrogen bonding.     

RG-CPA方程计算超临界CO2-醇体系汽液相平衡

综合考虑缔合作用和密度涨落的影响,将经重整化群修正的CPA方程（RG-CPA方程）扩展到二元体系汽液相平衡的计算。通过一个温度下的汽液相平衡数据回归得到二元交互作用参数,预测其他温度下的相平衡。采用这种方法计算了超临界CO₂与醇二元体系的汽液相平衡性质和临界曲线。结果表明,RG-CPA方程预测超临界CO₂与醇二元体系的气液相组成和密度具有较高的精度,液相组分平均绝对偏差为0.032,气相组分平均绝对偏差为0.019。与原始CPA方程相比,RG-CPA方程能更好地预测气液临界曲线。     

Modeling high pressure vapor–liquid equilibrium of ternary systems containing supercritical CO2 and mixed organic solvents using Peng–Robinson equation of state

High pressure vapor–liquid equilibrium (VLE) of CO₂-expanded organic solvents was investigated using Peng–Robinson-LCVM-UNIFAC equation of state. Bubble pressure of several ternary mixtures was predicted using this model and correlations were developed based only on binary experimental data. A sensitivity study of the LCVM parameter numerical value was done by considering the coherence between the mathematical features of the mixing rule and the quality of the simulation. The results provided by PR-LCVM-UNIFAC were compared with those ones given by Peng–Robinson equation of state using the classical quadratic mixing rules (PR-CMR). Despite the use of two adjustable parameters for each binary system, PR-CMR is not able to provide good results when applied to ternary systems. The capability of PR-LCVM-UNIFAC model to predict liquid mixture density for ternary systems using parameters regressed only from bubble pressure experimental data was also investigated. Due to the lack of liquid density experimental data, it was possible to perform only a qualitative assessment of the density curves calculated by this equation of state.     

Prediction of Solubility of Cholesterol in Supercritical Solvents

In this study the solubility of cholesterol was calculated in two supercritical pure solvents (carbon dioxide and ethane) as binary systems, and four supercritical solvent/co-solvent systems as ternary systems (cholesterol/carbon dioxide/methanol, cholesterol/ethane/acetone, cholesterol/ethane/hexane, cholesterol/ethane/propane) in various temperatures by SRK, PR, and SAFT equations of state. Pure molecular parameters of SAFT equation of state were obtained by fitting vapor pressure and liquid density data. Also the molecular parameters of cholesterol were obtained by fitting the solubility data of binary systems in one temperature, then they were used for the same system in other temperatures and for ternary systems with the same solvent. Results show that the SAFT equation of state can predict the trend and amount solubility of cholesterol in supercritical solvents much better than the other equations of state.     

状态方程模拟醇胺系统的密度和汽液相平衡

通过考虑醇胺分子间的缔合作用,结合先前开发的非缔合变阱宽链流体状态方程(SWCF-VREOS)建立了一个缔合方阱链流体状态方程,并利用方程模拟了醇胺系统的密度和汽液相平衡。通过关联不同温度下醇胺的饱和蒸气压和液体体积得到了18种醇胺流体的分子参数,新方程计算的饱和蒸气压和液体密度总的平均误差分别为0.94%和0.88%。结合简单的混合规则,将此方程扩展到混合系统。研究发现,建立的方程可预测二元和三元醇胺混合物的密度。当引入一个与温度无关的可调参数时,方程能满意关联二元系统的汽液相平衡数据,并可进一步预测多元混合系统的汽液相平衡,预示着新方程可模拟醇胺系统的相行为。     

变阱宽方阱链流体状态方程模拟制冷剂的汽液平衡

应用作者先前基于二阶微扰理论和PY2近似积分方程建立的可变阱宽方阱链流体状态方程模拟了纯制冷剂及其混合体系的汽液平衡。通过关联不同温度下制冷剂的饱和蒸气压和液体体积得到了18种纯制冷剂的分子参数,新方程计算的饱和蒸气压和液体体积总的平均偏差分别为1.11％和0.92％。结合简单混合规则,将此方程扩展到混合体系。研究发现,建立的方程可满意预测制冷剂二元混合体系除临界区附近外的汽液平衡,对两个三元体系汽液平衡的预测也取得了满意的效果,当引入一个与温度无关的可调参数时,关联精度大为提高,预示着新的方程可模拟制冷剂的汽液平衡。     

含原甲酸三乙酯体系等压汽液平衡的测定与关联

利用改进后Ｒｏｓｅ－Ｗｉｌｌｉａｍｓ釜测定了０．１０１３ＭＰａ下乙醇－原甲酸三乙酯，苯－原甲酸三乙酯体系的汽液平衡数据。实验数据通过了热力学一致性检验，采用威尔逊方程关联，获得较满意的结果，并对乙醇－苯－原甲酸三乙酯三元体系的汽液平衡进行了预测，计算精度可满足工程要求。     

EXTENSION OF SOAVE EQUATION OF STATE TO LIQUID DENSITY

On the basis of vapor pressures, volumes of saturated vapor and liquid, both parameters "a" and "b" in Soave equation of state are treated as temperature dependent and an extended Soave equation is proposed in this work. The VLE for 38 pure components including polar substances have been calculated. The comparison of calculated results with experimental data shows the prediction of liquid density is improved over Soave equation without losing the accuracy of prediction in vapor pressure and vapor density.     

含碘化物系统汽液平衡的研究

本文报导对含碘化物系统汽液平衡的研究结果。在我们所测定的一系列二元系以及一个三元系实验数据的基础上,主要研究了下列两个问题:（1）利用热力学方法,进行了温度、压力、液相与汽相组成间的相互推算。它有助于取得完整的基础数据,并判断数据的热力学一致性。（2）研究了数据的关联以及对多元系的推算。结果表明,虽然碘化氢水溶液是强电解质溶液,利用NRTL方程,并将其参数展开为温度的多项式,仍可满意地关联并准确预测多元系的汽液平衡。     

环己烷、正丁醇、甲苯有关二元体系加压相平衡

以环已烷、正丁醇、甲苯为代表,进一步研究了烷烃、芳烃和低级醇在加压下的相平衡规律。测定了有关3个二元体系在101.3、304.0、506.6、709.3、911.9kPa下汽液平衡数据,对实测数据进行了统一关联,计算结果与实测值符合良好。环己烷-正丁醇、正丁醇-甲苯体系在所测压力下均形成最低共沸点。     

Application of wilsonés equation to determination of vapor-liquid equilibrium data and heats of mixing for non-ideal solutions

A calculation technique, starting from total pressure data of binary systems and utilizing Wilsonés equation was developed, leading to isothermal vapor liquid equilibrium data for binary and ternary systems. Heats of mixing for ternary systems were also calculated from binary data.     

立方扰动硬链状态方程GE混合规则及其应用

扩展了立方扰动硬链(CSPHC)状态方程在天然气工业中通常遇到物质的纯组分参数, 并建立了纯组分参数的普遍化关联式; 将过量Gibbs自由能混合规则引入CSPHC状态方程, 以应用于高度非对称体系与极性体系相平衡性质计算。结合MPHC活度系数模型及Wilson 活度系数模型, 对13组二元体系的汽液平衡性质获得较满意的结果。     

CALCULATION OF VAPOR LIQUID EQUILIBRIUM AND EXCESS ENTHALPY WITH THE UNIQUAC EQUATION

The UNIQUAC equation was used for calculation of vapor liquid equilibrium (VLE)as well as excess enthalpy (h^E). Four sets of binary interaction parameters were applied: first, parameters estimated only from VLE data, then parameters from h^E data for both the original UNIQUAC equation and the Anderson modification, and finally parameters estimated from h^E and VLE data simultaneously. Calculations were performed for seven binary systems with polar components, representing different h^E behavior. The cross-prediction of h^E from VLE data works better than the reversed prediction. The model with parameters estimated simultaneously to both kinds of data can be applied successfully to both kinds of calculations, but it is a compromise between the models estimated from one kind of data.     

混合物MH-81状态方程的研究——从无限稀释活度系数预测混合物汽液平衡

本文由无限稀释活度系数求取混合物MH-81状态方程的二元相互作用参数,预测了二元混合物的汽液平衡,获得了较满意的结果。