Viscosities Of Pure Components Research Articles

Density and Viscosity of the Binary Systems Ethanol + Butan-1-ol, + Pentan-1-ol, + Heptan-1-ol, + Octan-1-ol, Nonan-1-ol, + Decan-1-ol at 0.1 MPa and Temperatures from 283.15 K to 313.15 K.

This article presents experimental viscosity and density data for binary systems containing ethanol and one of the following 1-alkanols as the second component: butan-1-ol, pentan-1-ol, heptan-1-ol, octan-1-ol, nonan-1-ol, and decan-1-ol. These properties were measured at 0.1 MPa and at five different temperatures, ranging from 283.15 K to 313.15 K. The viscosity data have also been correlated by a model which combines Eyring’s theory of viscous flow with a thermodynamic framework (Ind. Eng. Chem. Res. 2000, 39, 849). The model binary interaction parameters, for each of the binary systems, are also reported. The agreement between calculated and experimental data was rather good. The overall mean relative standard deviations did not exceed 0.01. The experimental viscosity deviations, obtained by the difference between the viscosity of the mixture and the mole fraction average of the pure component viscosities, were adjusted by means of Redlich–Kister polynomials. For all the systems studied negative values of viscosity deviations were obtained, for all temperatures, and over the whole mole fraction range.

Measurement and modeling the excess properties of binary and ternary mixtures containing [Hmim][BF4], 2-methyl-2-propanol, and propylamin compounds at 298.15 K using PFP theory

Density and viscosity of pure components 1-hexyl-3-methylimidazoliumtetrafluoroborate ([Hmim][BF4]), 2-methyl-2-propanol, and propylamin, along with binary mixtures of {x1[Hmim][BF4]+x22-methyl-2-propanol}, {x1[Hmim][BF4]+x2propylamin}, and {x12-methyl-2-propanol+x2propylamin}, and ternary mixture of {x1[Hmim][BF4]+x22-methyl-2-propanol+x3propylamin} were measured over the entire composition range at atmospheric pressure and 298.15K. The results of measuring the density and viscosity were used to calculate the excess molar volumes, partial molar volumes, and viscosity deviations. For all of the binary mixtures, the computed excess molar volumes were correlated by applying Redlich–Kister equation and Prigogine–Flory–Patterson (PFP) theory, while the obtained viscosities were correlated using McAllister, Hind, and Nissan equations. The obtained excess molar volumes, VmE, and viscosity deviations, Δη, of all of the binary mixtures and ternary mixture are negative over the entire composition range. The Cibulka equation was used to correlate the ternary excess molar volumes and viscosity deviations using the Redlich–Kister parameters of the binary mixtures.

Density and Viscosity Data for Binary Mixtures of 1-Alkyl-3-methylimidazolium Alkylsulfates + Water

Density and viscosity experimental data for binary mixtures of 1-alkyl-3-methylimidazolium alkylsulfates + water are reported using four ionic liquids: 1-butyl-3-methylimidazolium hydrogensulfate [C4mim][HSO4], 1-butyl-3-methylimidazolium methylsulfate [C4mim][C1SO4], 1-ethyl-3-methylimidazolium methylsulfate [C2mim][C1SO4], and 1-ethyl-3-methylimidazolium ethylsulfate [C2mim][C2SO4]. The choice of the ionic liquids allows us to compare the effects of incrementing the alkyl chain length in the cation and the anion on the measured thermophysical properties behavior. The Gardas and Coutinho group contribution methods were applied to the description of the pure component densities and viscosities allowing the estimation of new group contribution parameters, to extend the applicability of these methods to new ILs. Excess molar volumes and viscosity deviations were calculated and correlated by Redlich–Kister polynomial expansions.

Viscosity and rheological behaviour of carbon dioxide-expanded fish oil triglycerides: Measurement and modeling

Viscosity and rheological behaviour of carbon dioxide-expanded (CX) fish oil (FO) triglycerides (CXFO) were determined at 40, 55, and 70 °C at pressures of up to 12 MPa using a rotational rheometer equipped with a high pressure cell at shear rates of 100–500 s −1. The mass fraction of CO 2 ( w CO 2 ) in CXFO was determined at 40 and 55 °C at pressures of up to 25 MPa. The viscosity of CXFO determined at a shear rate of 300 s −1 decreased substantially with pressure due to dissolution of CO 2 in FO. Decrease in viscosity with pressure and hence w CO 2 was temperature dependent. The viscosity of CXFO decreased with a pressure increase from 0.1 to 12.2 MPa by about 90% (25 to 2.65 mPa s) and 70% (11.6 to 3.38 mPa s) at 40 °C and 70 °C, respectively. A new empirical model correlating the viscosity of CXFO to temperature and pressure was developed. The viscosity decreased up to w CO 2 levels of about 30% (w/w) then approaching a constant level. CXFO viscosity data were successfully correlated to w CO 2 and pure component viscosities using the empirical Grunberg and Nissan model. Rheological measurements showed dilatant flow behaviour for CXFO at elevated pressures, with the flow behaviour index approaching 1.5 at 12.4 MPa. Novel process development and design of equipment will benefit from a better understanding of such rheological behaviour.

Densities and Viscosities of Minority Fatty Acid Methyl and Ethyl Esters Present in Biodiesel

Biodiesels have several known components in their composition. The majority of components is well described in the literature, but a minority of components are poorly characterized. These are however required to develop reliable models to predict the biodiesel behavior. This work considers minor components of biodiesel: the polyunsaturated compounds (in C18), the monounsaturated (in C16, C20, and C22), and the long-chain saturated esters. In this work, densities and viscosities of pure fatty acid ester minor components of biodiesel fuel were measured (three ethyl esters and seven methyl esters), at atmospheric pressure and temperatures from (273.15 to 373.15) K. Correlations for the densities and viscosities with temperature are proposed. Three predictive models were evaluated in the prediction of densities and viscosities of the pure ethyl and methyl esters here reported. The GCVOL group contribution method is shown to be able to predict densities for these compounds within 1.5 %. The methods of Ceriani et al. (CM) and of Marrero et al. (MG) were applied to the viscosity data. The first show a better predictive capacity to provide a fair description of the viscosities of the minority esters here studied.

High-Pressure Viscosity Measurements for the Binary System Cyclohexane +n-Hexadecane in the Temperature Range of (318.15 to 413.15) K†

The viscosities of binary mixtures of cyclohexane and n-hexadecane at high pressures were measured for six different compositions with an electromagnetic viscometer in the range of (6.90 to 62.05) MPa at temperatures varying from (318.15 to 413.15) K, extending the data of Tanaka et al. with a vibrating crystal viscometer and that of Wakeham and co-workers utilizing a vibrating wire viscometer, for higher temperatures. The data were correlated with the molar additive mixing rule using temperature-dependent Gaussian functions in pressure for pure component viscosities. At higher temperatures, the curvature of the viscosity−pressure function changes significantly with composition for this asymmetric mixture.

The transport properties of an N2-H2 mixture of rarefied gases in the EPIDIF database

The principles of organization of the EPIDIF information-and-computation database are considered. Simultaneous processing of experimental data on the viscosity of pure components and mixture and on the coefficients of interdiffusion and thermal diffusion for a binary N2-H2 mixture of rarefied gases is performed. Nine parameters of three m-6 Lennard-Jones potentials of interaction of N2 and H2 molecules are determined within the least squares method. Tables of reference data for the considered transport properties are calculated in the temperature range from 100 to 1500 K and concentration range of 0–1(0.2). The parameters and their error matrix are included in the EPIDIF database.

Densities and Viscosities of N,N-Dimethylformamide + N-Methyl-2-pyrrolidinone and + Dimethyl Sulfoxide in the Temperature Range (303.15 to 353.15) K

Densities and viscosities of the binary mixtures of N,N-dimethylformamide + N-methyl-2-pyrrolidinone and N,N-dimethylformamide + dimethyl sulfoxide have been measured at different temperatures and atmospheric pressure, over the entire composition range. From these data, excess molar volumes (VE) were calculated for each of the systems. The densities and viscosities of pure components have been compared with those reported by other authors available in the literature. The ρ and η were fitted to a Redlich−Kister equation, and the coefficients of the Redlich−Kister equation and the estimate of standard deviation are also presented.

Densities and Viscosities of (N,N-Dimethylformamide + Water) at Atmospheric Pressure from (283.15 to 353.15) K

Densities and viscosities of (N,N-dimethylformamide + water) have been measured from T = (283.15 to 353.15) K in the entire mole fraction composition. Densities are measured with a vibrating tube densimeter, while two different Cannon-Fenske viscosimeters are used for the viscosity measurements. Excess molar volumes and viscosity deviations from the composition weighted average of the pure component viscosities are calculated from experimental measurements and represented with Redlich–Kister equations. Excess molar volumes present negative deviations from ideality at all investigated temperatures and become more negative with decreasing temperature. Viscosity deviations are positive for all the temperatures and mole fractions considered in this work.

Viscosities of Gas Mixtures at Low Pressures

Empirical correlation is developed to predict viscosities of gas mixtures at low pressures and different temperatures. This proposed correlation depends on mole fractions of gas, molecular weight, boiling point, critical pressure and viscosity at 25°C of component 1, and critical temperature for components and viscosity of pure components. The proposed correlation has been verified using 55 data points, and shows significantly better correlation with an average absolute error of 2%.

Excess Molar Volumes and Viscosities of Binary Mixtures of p-Cresol with Ethylene Glycol and Methanol at Different Temperature and Atmospheric Pressure

Densities and viscosities of the binary mixtures of p-cresol + ethylene glycol and p-cresol + methanol mixtures have been measured at different temperatures and atmospheric pressure, over the entire composition range. From these data, excess molar volumes and viscosity deviation were calculated for each of the systems. The densities and viscosities of pure components have been compared with those reported by other authors available in the literature. The excess molar volumes, V E, and viscosity deviations, Δη, were fitted to a Redlich−Kister equation, and the coefficients of the Redlich−Kister equation and estimate the standard error are also presented.

Viscosity of the System KF–K2NbF7–Nb2O5

Abstract The viscosity of melts of the system KF–K2NbF7–Nb2O5 has been measured using computerized torsion pendulum method. An equation describing the dependency of the viscosity in logarithm values on composition at 1173 K was calculated by multiple linear regression analysis. The sum of viscosities of pure components in logarithm values multiplied by their mole fraction was used as an “additive” behaviour. In the concept of modified Redlich–Kister's type equation binary interactions of the particular components were found.

Modeling viscosity of concentrated and mixed-solvent electrolyte systems

A comprehensive model has been developed for calculating the viscosity of aqueous or mixed-solvent electrolyte systems ranging from dilute solutions to fused salts. The model incorporates a mixing rule for calculating the viscosity of solvent mixtures and a method for predicting the effect of finite electrolyte concentrations. The mixing rule represents the viscosity of multi-component solvent mixtures using molar volumes and viscosities of pure components together with binary parameters. With this mixing rule, the viscosity of ternary systems can be accurately predicted using parameters determined from only binary data. The effect of electrolyte concentration on viscosity is modeled by combining a long-range electrostatic term obtained from the Onsager–Fuoss theory, a contribution of individual ions, which is quantified by the Jones–Dole B coefficients, and a contribution of specific interactions between ions or neutral species. Formulations have been developed for the contributions of individual ions and species–species interactions to account for the effect of multiple solvents. In addition to solvent composition, the species–species interaction term is also a function of ionic strength. The model accurately reproduces the viscosity of systems such as salts in water, organic or mixed water-organic solvents and aqueous acids or bases up to the pure solute limit. The model has been coupled with thermodynamic equilibrium calculations to reproduce the effects of complexation or other ionic reactions on viscosity.

Prediction of the Liquid Viscosities of Pure Components and Mixtures Using Neural Network and ASOG Group Contribution Methods

This study proposes a simple method for predicting liquid viscosities of pure components and mixtures from chemical structures only. Initially, the constants B and T 0 used in a modified Andrade equation for pure liquid viscosity were predicted using a three-layer neural network method with an error back-propagation learning algorithm. The network was trained using 194 data sets and information concerning 29 chemical groups was used as descriptors of input. The components covered were paraffines, olefins, alkynes, aromatic hydrocarbons, chlorides, bromides, alcohols, ketones, esters, ethers, aldehydes and organic acids. The temperature range is approximately the melting point to the bubble point of the compounds and the average and maximum deviations of viscosity are 9.5 and 14.3%, respectively. The viscosities of binary systems were predicted using the ASOG-VISCO group contribution method. This study covers mixtures composed of CH2, ArCH, CyCH, OH, H2O, CO and COO groups with a temperature range of 293.15–303.15 K. and an average deviation of viscosities of 4.5%.

AUA model NEMD and EMD simulations of the shear viscosity of alkane and alcohol systems

The viscosities of alkanes (propane, isobutane, nonane), alcohols (ethanol, propanol, isopropanol, 2-butanol) and isopropanol+nonane mixtures were calculated using non-equilibrium and equilibrium molecular dynamics (NEMD and EMD) simulation methods. The nonane, isopropanol and nonane+isopropanol mixture simulations were performed in response to the First Industrial Simulation Challenge. Intermolecular interactions were modeled using an anisotropic united-atom Buckingham exponential-6 potential. The force field parameters were optimized using pure component viscosity data. The resulting viscosities are compared with literature values, with the result that the anisotropic united-atom model together with the exponential-6 model can give good predictions of the viscosity of n-alkane and alcohol systems.

Structural and thermodynamic aspects in the molybdenum melts of the system KF–K2MoO4–SiO2

The complex physico-chemical analysis of the system KF–K 2 MoO 4 –SiO 2 , based on the phase diagram, density, surface tension and viscosity measurements, was performed. The phase diagrams of the binary systems as well as that of the ternary system in the range up to 50% SiO 2 were measured using the thermal analysis method. The results proved the presence of the congruently melting compound K 3 FMoO 4 at 751 °C in the binary melt KF–K 2 MoO 4 . The strong positive deviation from ideal behaviour of the ternary system KF–K 2 MoO 4 –SiO 2 was ascribed to the formation of heteropolyanions [SiMo 12 O 40 ] 4− in the melt. In the investigated concentration range of the ternary system, no eutectic point has been found. It lies most probably beyond the investigated part of the system. The probable inaccuracy in the calculated ternary phase diagram is 5.9 °C. The density of the melts of the system KF–K 2 MoO 4 –SiO 2 was measured using the Archimedean method. Based on the obtained density data the molar volume, partial molar volume and excess molar volume of the melts were calculated in order to consider the possible chemical interactions of components. The degree of thermal dissociation of the additive compound K 3 FMoO 4 was calculated based on both the thermodynamic analysis of the phase diagram and the volume properties of the investigated system. It was found that the degree of the thermal dissociation of K 3 FMoO 4 at the melting point attains the value α o =0.81. The dissociation enthalpy, calculated on the basis of the density values is Δ H (dis, K 3 FMoO 4 )=18.8 kJ mol −1 . The surface tension of the molten system KF–K 2 MoO 4 –SiO 2 has been determined using the maximum bubble pressure method. Based on the obtained data the concentration dependence of the surface tension and of the surface tension excess of the investigated system was calculated. The viscosity of melts of the system KF–K 2 MoO 4 –SiO 2 has been measured using the computerised torsional pendulum method. The sum of viscosities of pure components in logarithm values multiplied by their mole fraction was used as an ‘additive’ behaviour. A multiple linear regression analysis was performed to obtain coefficients of the modified Redlich–Kister's type equation. Binary and ternary interactions of the particular components were found. X-ray powder diffraction patterns and IR spectra of the certain quenched powdered samples of both binary and ternary mixtures were recorded. By both techniques the presence of starting compounds and the presence of another compounds, as well, was detected. Some of these compounds were recognized based on the known data. The remaining data were attributed to the possible expected compounds.

Structural and thermodynamic aspects in the molybdenum melts of the system KF–K 2MoO 4–SiO 2

The complex physico-chemical analysis of the system KF–K 2MoO 4–SiO 2, based on the phase diagram, density, surface tension and viscosity measurements, was performed. The phase diagrams of the binary systems as well as that of the ternary system in the range up to 50% SiO 2 were measured using the thermal analysis method. The results proved the presence of the congruently melting compound K 3FMoO 4 at 751 °C in the binary melt KF–K 2MoO 4. The strong positive deviation from ideal behaviour of the ternary system KF–K 2MoO 4–SiO 2 was ascribed to the formation of heteropolyanions [SiMo 12O 40] 4− in the melt. In the investigated concentration range of the ternary system, no eutectic point has been found. It lies most probably beyond the investigated part of the system. The probable inaccuracy in the calculated ternary phase diagram is 5.9 °C. The density of the melts of the system KF–K 2MoO 4–SiO 2 was measured using the Archimedean method. Based on the obtained density data the molar volume, partial molar volume and excess molar volume of the melts were calculated in order to consider the possible chemical interactions of components. The degree of thermal dissociation of the additive compound K 3FMoO 4 was calculated based on both the thermodynamic analysis of the phase diagram and the volume properties of the investigated system. It was found that the degree of the thermal dissociation of K 3FMoO 4 at the melting point attains the value α o=0.81. The dissociation enthalpy, calculated on the basis of the density values is Δ H(dis, K 3FMoO 4)=18.8 kJ mol −1. The surface tension of the molten system KF–K 2MoO 4–SiO 2 has been determined using the maximum bubble pressure method. Based on the obtained data the concentration dependence of the surface tension and of the surface tension excess of the investigated system was calculated. The viscosity of melts of the system KF–K 2MoO 4–SiO 2 has been measured using the computerised torsional pendulum method. The sum of viscosities of pure components in logarithm values multiplied by their mole fraction was used as an ‘additive’ behaviour. A multiple linear regression analysis was performed to obtain coefficients of the modified Redlich–Kister's type equation. Binary and ternary interactions of the particular components were found. X-ray powder diffraction patterns and IR spectra of the certain quenched powdered samples of both binary and ternary mixtures were recorded. By both techniques the presence of starting compounds and the presence of another compounds, as well, was detected. Some of these compounds were recognized based on the known data. The remaining data were attributed to the possible expected compounds.

Liquid Viscosity Model for Polymer Solutions and Mixtures

A simple liquid viscosity model for multicomponent mixtures containing polymers is presented. This model is essentially a new mixing rule for calculating the Newtonian viscosity of mixtures over the entire composition range using the pure-component viscosities. A modified Mark−Houwink model is applied to calculate the Newtonian viscosity of pure polymer melts, and the Andrade/DIPPR correlation model is used to calculate the viscosity of pure conventional components. Two binary parameters, one symmetric and one antisymmetric, are introduced to capture nonideal mixing behavior of Newtonian viscosity in polymer solutions. Applications to polystyrene solutions and poly(ethylene glycol) solutions are presented.

The Prediction of Viscosity for Mixtures Using a Modified Square Well Intermolecular Potential Model

AbstractIn the chemical and process industries, the viscosity of pure components and mixtures is a required fluid property in the areas of hydraulics, heat transfer, and mass transfer. Hence, there is a definite need for a reliable and accurate method for viscosity calculations of mixtures that is applicable over the entire density range for a wide variety of components.The Modified Square Well Intermolecular Potential viscosity model developed by Monnery et al. (1998) to predict pure component viscosities offers a good compromise between theory and applicability. In this work, the square well model is extended to mixtures. A total of 276 binary mixtures, including non‐polar and polar components, were used to regress binary interaction parameters for the mixing rules. The predicted mixture viscosities had a 10% average absolute deviation for the entire density range that included the gas, liquid, and dense phases.

Viscosity and Thermodynamics of Viscous Flow for the Systems of Isomeric Pentanols with Toluene

Viscosities of the isomers of pentanol (1-pentanol, 2-pentanol and 3-pentanol) and their binary solutions with toluene in the whole range of composition have been measured at different temperatures between 303.15 and 323.15 K. Viscosities of pure components have been plotted against temperature and for binary mixtures, against the mole fraction of pentanols at different temperatures. At lower concentrations of pentanols, viscosities increase slowly, but at an increasing rate on the continued addition of pentanols in toluene. The excess viscosities and excess free energies of activation for viscous flow are in the order, 3-pentanol + > 2-pentanol + > 1-pentanol + toluene. Excess entropies are found to be negative for the systems 2-pentanol + toluene and 3-pentanol + toluene in the whole range of composition, but for 1-pentanol + toluene the values are small and they are either positive or negative at different compositions. The disruption of H-bonds in pentanols either by thermal effect or by the force of dispersion is in the order: 3-pentanol > 2-pentanol > 1-pentanol. This effect is considered to be quite significant in explaining the temperature dependence of viscosity of pure pentanols, negative excess values of viscosity, free energy and entropy for viscous flow as well as their orders for all the systems.