三元体系液体混合物粘度的工程应用预测模型

从普遍适用的热力学关系出发，对Eyring模型进行修正，得到一个新的修正Eyring粘度模型。对三元体系液体混合物粘度的预测结果表明，与McAllister二维三体模型相比，修正的Eyring粘度模型预测结果较优，因此其修正更为合理，更具工程应用的前景。     

若干液体混合物的粘度和密度测定

本文用比重管和毛细管粘度计测定了乙酸乙酯-四氯化碳-环己烷-苯、甲醇-乙醇-异丙醇-四氯化碳、水-甲醇-乙醇-异丙醇、水-甲醇-丙酮-醋酸四个四元体系及包含的二元、三元体系在298.15K的密度和粘度。     

液体烃及其混合物粘度预测方法的研究进展

综述了液体烃及其混合物粘度预测方法的研究进展。内容主要包括各种预测方法的理论基础、预测的具体方程形式,以及预测的平均误差。本文所选择的方法都是一些应用比较广泛比较有发展前景的方法。     

液体混合物密度和粘度的实验测定

<正> 本文分别在四个温度下,对乙酸乙酯+正己烷、氯仿+正己烷、四氯化碳+丙酮、乙酸乙酯+丙酮、四氯化碳+甲苯、氯苯+甲苯这6个二元液体混合物的密度和粘度进行了实验测定。包括纯物质在内,总的实验点数为244点。混合物均是涉及极性组分的系统。 根据所测二元系具有易挥发的特点,采用特别加工的密度瓶和乌氏(Ubbelohde)粘度计。     

含盐液体混合物的粘度 Ⅲ．水—有机溶剂—盐三元溶液粘度的拟二元溶质聚集模型

结合水溶液粘度的溶质聚集模型和拟二元方法，作者提出了一个适用于水－有机溶剂－盐三元溶液粘度关联的拟二元溶质聚集模型（PSAV），能够成功地应用于以盐饱和与不饱和水溶液粘度的关联，平均相对偏差约1．0％，比作者早先提出的拟二元局部组成模型（平均相对偏差为2－5％）有较大的改善，对于盐不饱和溶液，模型参数随浓度和温度呈有规律的变化。     

Eyring模型的修正及液体混合物粘度的研究

<正>在化工传质和流体力学中,粘度是一个不可缺少的物性.为此,已建立了许多计算液体混合物粘度的经验和半经验方程,其中不少建立在 Eing粘度理论的基础上,但这些方程都含有 2个或多个     

从液体混合物的粘度数据推算汽液平衡数据

<正>液体混合物的汽液平衡数据和粘度数据都是基本的物性数据,人们很早就开始了对它们的研究,并取得了不小的进展.对于汽液平衡的研究,人们提出了许多溶液理论和活度系数方程,例如Flory-Huggins方程,Van Laar方程,Margules方程,Wilson方程和其修正方程,NRTL方程以及UNIQUAC方程等;对于液体混合物的粘度,人们也提出了许多流体粘度理论,其中最著名的是Eyring反应速率理论.作者曾应用这一理论建立了一个新的液体混合物粘度方程,用于关联二元体系的粘度数据和推算多元体系的粘度数据,结果令人满意.     

二元液体混合物非理想吸附平衡数据的预测

根据气相吸附和液相吸附的热力学一致性条件 ,从溶液理论、表面热力学出发并结合相交换模型 ,提出从气相吸附平衡数据预测二元液体混合物吸附平衡的模型 ,模型中仅含 4个未知参数 .应用该模型对二元液体吸附体系进行了预测 ,结果与实验数据相当吻合     

二元液体混合物的沸腾传热

一、混合物沸腾传热特点及机理沸腾是一种具有相变的传热过程,由于它在工业应用中的重要性,引起许多学者开展研究。在过去的几十年中,对单组分沸腾特性的研究作了不少努力。然而在实际工作中涉及的往往是混合物的沸腾问题,尤其是     

含非对称Gemini离子液体二元混合体系的体积和黏度性质

在温度分别为293.15、303.15、313.15、323.15和333.15 K及大气压下,系统测定了非对称Gemini离子液体,1-(3-(三甲基铵)丙-1-基)-3-甲基咪唑双氰胺盐([N₁₁₁C₃MIM][N(CN)₂]₂),分别与乙腈(MeCN)、甲醇(MeOH)、乙醇(EtOH)所组成的二元混合物的密度和黏度。由密度和黏度值分别计算了二元混合物的超额摩尔体积(V_{\mathrm{m}}^{\mathrm{E}})和超额黏度(Δη)。V_{\mathrm{m}}^{\mathrm{E}}和Δη随组成的变化关系由Redlich-Kister方程进行了回归,得到方程参数。结果表明,V_{\mathrm{m}}^{\mathrm{E}}和Δη值与理想溶液间为负偏差,且存在最小值,说明二元体系中[N₁₁₁C₃MIM][N(CN)₂]₂和溶剂分子间相互作用力更强,同时与所研究分子的大小和形状的差异有关。同时,V_{\mathrm{m}}^{\mathrm{E}}和Δη随温度的变化关系表明,温度对研究混合物中的分子间相互作用有很大影响。     

A new one parameter viscosity model for binary mixtures

The Grunberg & Nissian equation with one parameter is widely recommended in the viscosity calculation. However, it is demonstrated that this equation fails to generate satisfactory results for size‐asymmetric mixtures containing large and small molecules. In this work, a new one parameter viscosity model for binary mixtures has been developed on the basis of Eyring's absolute reaction rate theory and the Flory‐Huggins equation. The concept of molecular surface fraction is introduced for modeling liquid mixture viscosities. The viscosity calculations of the new equation are compared with the Grunberg & Nissian equation for a broad range of chemical mixtures including 527 binary systems (containing 63 binary ionic liquid cosolvent systems) and total 17,268 viscosity points. The new equation was found to have an improved performance over the frequently employed Grunberg & Nissian equation, especially for size‐asymmetric mixtures containing large and small molecules. © 2010 American Institute of Chemical Engineers AIChE J, 57: 517–524, 2011     

Change in viscosity of softening coal upon heating with its liquid content. Part I: linear relationship between logarithm of viscosity and liquid fraction

A variable-force-loading needle penetrometry and a proton magnetic resonance analysis were performed for in situ measurements of shear-rate-independent viscosity of softening coal pellet upon heating, η, and the fraction of mobile hydrogen existing in the liquid phase, φ_mh, respectively. During isothermal heating of the pellet at temperature in a range from 680 to 730 K, φ_mh changed with time via a maximum while η did inversely. At every temperature examined, the time for the maximum φ_mh coincided with that for the minimum η. This result qualitatively validated the experimental definition of the liquid fraction in the softening coal as a liquid/solid suspension by φ_mh. Further analysis of the results revealed that the logarithm of η, which changes in a range from 10¹⁰ to 10⁴ Pa s upon isothermal heating, is correlated linearly with the liquid fraction ranging from 0.1 to 0.5. For each of the pellets made of two different coals, it was found that the logarithm η and φ_mh varied being governed by a single linear relationship upon both isothermal heating and non-isothermal heating. Such a single relationship, which was valid over a temperature range from 600 to 800 K, suggested fairly small temperature dependency of the viscosity of liquid in the softening coal.     

Spectroscopic study of anthraquinone dye/amphiphile systems in binary aqueous/organic solvent mixtures

The absorption spectra of novel dye/amphiphile systems, in which the dye is a 1,5-bis-(R-phenylamino)anthraquinone [R = o-methoxy, o-ethoxy, H] and the solvents are either organic or H₂O/organic solvent mixtures, have been investigated. It was found that an abrupt λ_max shift of more than 80 nm occurred for the system containing dye having R = o-methoxy and the amphiphile (poly-bis-(2,2′-dimethyl-5,5′-disulphonate)naphthylmethane disodium salt) in pure solvents with a specific E_T(30) value or in H₂O/DMF (N,N-dimethylformamide) mixtures containing at least 38% water. This type λ_max shift was not observed when solvent mixtures containing the other two dyes were studied. The origin of the pronounced λ_max shift is discussed in detail. It is believed that this shift arises mainly from changes in the solvation state of hydrophobic dye having R = o-methoxy when water is introduced in the presence of a dispersing agent. In this regard, dye is converted from the monomolecular state to dispersed particles.     

An investigation of the characteristics of Maxwell-Stefan diffusivities of binary mixtures in silica nanopores

Diffusion of pure components (hydrogen (H₂), argon (Ar), krypton (Kr), methane (C1), ethane (C2), propane (C3), n-butane (nC4), and n-hexane (nC6)) in silica nanopores with diameters of 1, 1.5, 2, 3, 4, 5.8, 7.6, and 10 nm were investigated using molecular dynamics (MD). The Maxwell-Stefan (M-S) diffusivity (?_i,s) and self-diffusivities (D_i,self,s) were determined for pore loadings ranging to 10 molecules nm⁻³. The MD simulations show that zero-loading diffusivity ?_i,s(0) is consistently lower, by up to a factor of 10, than the values anticipated by the classical Knudsen formula; the differences increase with increasing adsorption strength. Only when the adsorption is negligible does the ?_i(0) approach the Knudsen diffusivity value.MD simulations of diffusion in binary mixtures C1-H₂, C1-Ar, C1-C2, C1-C3, C1-nC4, C1-nC6, C2-nC4, C2-nC6, and nC4-nC6 in the different pores were also performed to determine the three parameters ?_1,s, ?_2,s, and ?₁₂, arising in the M-S formulation for binary mixture diffusion. The ?_i,s in the mixture were found to be practically the same as the values obtained for unary diffusion, when compared at the same total pore loading. Also, the ?_i,s of any component was practically the same, irrespective of the partner molecules in the mixture. Furthermore the intermolecular species interaction parameter ?₁₂, could be identified with the binary M-S diffusivity in a fluid mixture at the same concentration as within the silica nanopore. The obtained results underline the overwhelming advantages of the M-S theory for mixture diffusion in nanopores.Our study underlines the limitations of the commonly used dusty-gas approach to pore diffusion in which Knudsen and surface diffusion mechanisms are considered to be additive.     

Predicting thermal conductivity of binary liquid mixtures on basis of coordination number

By applying a model of a randomly mixed packing of spheres of two sizes to binary liquid mixtures, the thermal conductivity of the mixture is related to the physical properties of each component through the number of contact points. Further, two parameters are introduced to account for the effect of the hydrogen bond and are correlated with the Lennard-Jones (6-12) parameters σ and ?, or the boiling temperature. In comparing the calculated values with the experimental data for 13 aqueous liquids and 21 non-aqueous liquid systems, the present equation turns out to be more accurate than previous ones.     

The prediction of the viscosity of liquid hydrocarbons and their mixtures as a function of temperature and pressure

We present empirical models for calculating the viscosity of hydrocarbons and their mixtures, including with carbon dioxide, over a wide range of temperatures and pressures. The procedure is simple, will always yield a reasonable answer, and is surprisingly accurate for the fluids and conditions we have examined. Indeed, our model is more accurate than other models currently in use, including the much more complicated corresponding states methods. Further, in many cases, the model is completely predictive, requiring only the normal boiling point as input data. The predictive ability of the model is also tested with several petroleum mixtures.     

Extending the EMMS/bubbling model to fluidization of binary particle mixture: Formulation and steady-state validation

The EMMS/bubbling model originally proposed for fluidization of monodisperse particles is extended to fluidization of binary particle mixture in this study. The dense and dilute phases are considered to comprise of two types of particles differing in size and/or density. Governing equations and the stability condition are then formulated and solved by using an optimization numerical scheme. The effects of bubble diameter are first investigated and a suitable bubble diameter correlation is chosen. Preliminary validation for steady state behavior shows the extended model can fairly capture the overall hydrodynamic behaviors in terms of volume fraction of bubbles and average bed voidage for both monodisperse and binary particle systems. This encourages us to integrate this model with CFD for more validations in the future.     

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.