Viscosity Of Binary Mixture Research Articles

Viscosity of imidazolium ionic liquids and mixtures of ILs from entropy scaling using the PC-SAFT and ePC-SAFT equations of state

Entropy scaling is a promising method for the development of engineering models for transport properties of ionic liquids (ILs). Here we present two entropy scaling models for the viscosity of ionic liquids and their mixtures at various temperatures and pressures: 1) a molecular-based approach treating each IL as one pure species and using the PC-SAFT equation of state (EoS); and 2) treating each ion as a separate species and using the ePC-SAFT EoS. Both approaches were correlated to viscosity data of 12 ionic liquids from the imidazolium cation class and three different anions comprising 4233 data points with overall average absolute deviations (%AARDs) of less than 8 % over a wide range of temperature and pressures. The ion-based approach was better able to correlate IL viscosity at low temperatures and/or high pressure (to 4011 bar) than the molecular approach. The functional entropy-scaling coefficients for both models were regressed as linear functions of molecular weight, which allowed good prediction of another nine ionic liquids not in the training set. Interestingly, both approaches well predict the viscosity of binary mixtures of imidazolium ionic liquids. In addition, the effect of various reference viscosities and comparison with the Peng-Robinson EoS was performed.

Molecular interaction studies between acetylcholine with primary alcohols

Ultrasonic velocity, density and viscosity of binary mixtures of Acetylcholine and Propanol have been measured at room temperature 303K. Using the measured velocity the thermodynamic parameters such as adiabatic compressibility (β), inter molecular free length (Lf), Acoustic impedance (Z), free volume (VE) have been calculated. It has been established that ultrasonic velocity decreases with increasing the mole fraction. The results show a nonlinear variation of acoustical parameters, confirms the presence of molecular associative nature in this binary mixture.

Some experimental and theoretical studies of diethylene glycol diethyl ether and 2-alkanol mixtures

Experimental density and dynamic viscosity data for the diethylene glycol diethyl ether +2-alkanol (C3 to C6) mixtures have been published at 293.15 K, 303.15 K, 313.15 K, and 323.15 K and at pressure of 0.1 MPa. Excess molar volume and deviation in dynamic viscosity were obtained from experimental data and correlated with Redlich–Kister equation, from the values obtained, the interaction forces were studied. Perturbed chain-statistical associating fluid theory equation of state was used for modeling the density for pure fluids and mixtures. Free volume theory coupled to Perturbed chain-statistical associating fluid theory equation of state was used to modeling the viscosity of pure fluids and mixtures; in the case of binary mixtures, we proposed a simple mixing rule and used the Pourabadeh et al. mixing rule. Good results in the prediction and correlation of experimental liquid density and dynamic viscosity for binary mixtures were obtained, 0.12% and 2.28%, respectively.

Molecular Modeling of Supercritical Processes and the Lattice—Gas Model

The existing possibilities for modeling the kinetics of supercritical processes at the molecular level are considered from the point of view that the Second Law of thermodynamics must be fulfilled. The only approach that ensures the fulfillment of the Second Law of thermodynamics is the molecular theory based on the discrete–continuous lattice gas model. Expressions for the rates of the elementary stage on its basis give a self-consistent description of the equilibrium states of the mixtures under consideration. The common usage today of ideal kinetic models in SC processes in modeling industrial chemistry contradicts the non-ideal equation of states. The used molecular theory is the theory of absolute reaction rates for non-ideal reaction systems, which takes into account intermolecular interactions that change the effective activation energies of elementary stages. This allows the theory to describe the rates of elementary stages of chemical transformations and molecular transport at arbitrary temperatures and reagent densities in different phases. The application of this theory in a wide range of state parameters (pressure and temperature) is considered when calculating the rates of elementary bimolecular reactions and dissipative coefficients under supercritical conditions. Generalized dependencies are calculated within the framework of the law of the corresponding states for the coefficients of compressibility, shear viscosity, and thermal conductivity of pure substances, and for the coefficients of compressibility, self- and mutual diffusion, and shear viscosity of binary mixtures. The effect of density and temperature on the rates of elementary stages under supercritical conditions has been demonstrated for a reaction’s effective energies of activation, diffusion and share viscosity coefficients, and equilibrium constants of adsorption. Differences between models with effective parameters and the prospects for developing them by allowing for differences in size and contributions from the vibrational motions of components are described.

A New Mathematical Model for the Characterization of Viscosity Variations in the Aqueous Solutions of Monoalcohols and Polyalcohols

This study aims to investigate the viscosity of binary mixtures of water with different monoalcohols and polyalcohols. The viscosity values of the mixtures of methanol, ethanol, 1-propanol, and 2-propanol were taken from a study published by Herraez and Belda (2004). The values for ethylene glycol, glycerin, and sorbitol were measured using a similar protocol. The viscosity of the mixture is expressed as a function of the molar fraction of the alcohols that ranges from 0 (pure solvent, water in this case) to 1 (pure solute). To represent the viscosity of these mixtures, a new variable, Φ, was introduced. This representation provides a function, η = f(Φ), that has an exponential nature, with which excellent correlation coefficients are achieved with only one coefficient for monoalcohols or two coefficients for polyalcohols. Additionally, the variable Φ highlights the possible critical points, where physicochemical interactions occur between the components of the mixture.

Molecular interaction between ester with ethanol at different temperature using ultrasonic technique

In this work, thermodynamic and acoustic properties of binary liquid mixtures of ethyl propionate with ethanol are determined at various temperatures and under ambient pressure. Experimental ultrasonic velocity, density, and viscosity of binary mixtures were measured at different temperatures of 308 K, 313 K, 318 K, 323 K, 328 K, and 333 K. Acoustical parameters such as acoustic impedance (Z), adiabatic compressibility (βa), Intermolecular free length (Lf), relaxation time (τ), internal pressure (π), and thermodynamic parameters like Gibb’s free energy (ΔG) and enthalpy (H) have been computed from the above primary parameters. The excess free length (LfE), excess internal pressure (πE) and excess enthalpy (HE) were derived using experimental data. Negative excess values are obtained for the binary system (ethyl propionate + ethanol). The non-linear variations are found for the thermo -acoustic parameters which imply the presence of complex formation in the binary system. The obtained results have been discussed in detail.

Effect of water or ethanol on the excess properties of deep eutectic solvents (tetrabutylammonium bromide + formic acid/propionic acid)

The density and viscosity of binary mixtures of [tetrabutylammonium bromide + formic acid/propionic acid] with water or ethanol were determined in the entire molar fraction range of 288.15–318.15 K. The influences of temperature, deep eutectic solvents (DESs) composition and molar fraction, as well as different solvents on the excess molar volume, apparent molar volume, partial molar volume, viscosity deviation and excess viscous flow activation Gibbs free energy of the binary mixed system were investigated in detail. The interaction of DESs with solvent molecules in binary system mixtures is discussed. It demonstrated the existence of hydrogen bonding between DESs and solvent molecules, and that the interaction between DESs and ethanol was stronger than DESs-water. By introducing the concepts of relative volume and relative viscosity, the viscosity values of the binary mixed system were predicted by combining the Redlich-Kister equation. This study is expected to provide a theoretical reference for the future application of DESs.

Machine learning for predicting the viscosity of binary liquid mixtures

Viscosity is an important parameter in process engineering and is a key design objective for application areas including the coatings, lubricants, personal care, and pharmaceutical industries. The lack of reliable and general methods for predicting the viscosities of mixtures creates a barrier for modern process engineering and product design. In this work, we developed a graph-based neural network architecture and applied it to the problem of predicting the viscosity of binary liquid mixtures as a function of composition and temperature. To obtain a high-quality training dataset, we also developed an automated curation pipeline and applied it to a large dataset collected from the literature by the National Institute of Standards and Technology (NIST) to be used as training data. The resulting model predicts viscosity with an MAE of 0.043 and an RMSE of 0.080 in log cP units (base 10). To improve the dependability of the model, we developed a classifier that evaluated the reliability of a prediction based on the variance between an ensemble of models. Using this approach, the model had an effective MAE of 0.029 and RMSE of 0.047 for predictions that were assessed as reliable (80% of the test set). Overall, this work provides 1) a large set of curated viscosity data that can be used for future machine learning efforts, 2) a new, graph-based deep learning approach for predicting the viscosity of binary mixtures, and 3) an illustrative case study for how deep learning can be used for accurate and reliable property prediction.

Thermodynamic properties, viscosity modelling and FTIR studies of binary liquid mixtures of 2-isopropoxy ethanol with amines at different temperatures

Thermodynamic and spectral analysis for binary liquid mixtures of 2-isoporopxy ethanol with diisopropylamine, di-n-butylamine and tri-n-butylamine has been carried out in the present discussion. For this purpose, measurements of density, speed of sound and viscosity for binary mixtures were carried out over the entire composition range and at temperatures (298.15, 303.15 and 308.15) K. Various excess and deviation parameters were evaluated using the measured properties. Behaviour of calculated parameters was found quite sensitive towards the intermolecular interactions. Change in behaviour of these parameters with composition and temperature has been discussed in terms of intermolecular interactions due to physical and chemical effects among unlike molecules. Excess parameters were correlated with composition using Redlich-Kister polynomial. Existing theories and semi-empirical relations for viscosity were tested. Spectroscopic methods were also utilized to support the results obtained from above calculated parameters qualitatively.

A new correlation to calculate the viscosity of binary mixtures of heavy or extra-heavy crude oil and light hydrocarbons using the Arrhenius-Lederer equation

Heavy crude oils are commonly mixed with lighter crude oils to reduce heavy oil viscosity and to ensure the flow through the pipeline system. Viscosity, as is well known, is a crucial property for designing and sizing offshore and onshore facilities for producing and transporting crude oil. When not available experimentally, the viscosity of mixed crudes can be obtained from theoretical approaches such as the Arrhenius-Lederer equation depending only on bulk properties (density and viscosity) of mixture components, and an adjustable parameter (α), which allows calculations to match experimental data. This work presents a new correlation for calculating the rescaled parameter proposed by Lederer for the Arrhenius equation to determine the viscosity mixtures of heavy and light hydrocarbons. The proposed correlation was developed considering experimental data of binary mixtures of paraffinic hydrocarbons, diesel, and heavy oil over a wide range of temperature conditions (from 293 to 343 K), fluid density ratios (from 1.014 to 1.40), and viscosity ratios (1.3 to 311,000). For viscous fluids, which exhibited non-Newtonian behavior, viscosity on the first Newtonian region is considered. The correlation was tested to predict the viscosity of biodiesel-diesel, heavy crude oil-diesel, bitumen-heptane, and eicosane-decane binary mixtures from 308 to 448 K and pressures up to 10 MPa. Finally, for assessing the predictive capabilities of the new correlation, the viscosity of several mixtures was estimated. The first consisted of mixtures formed by three oils at different compositions, whereas the last consisted of a recombined live oil and supercritical CO2. Predicted viscosities are in better agreement with experimental data than those estimated from Shu’s correlation. The total mean absolute percentage error was 6.66 and 19.32 for the proposed and the Shu correlation, respectively.

Densities, Viscosities, and Derived Properties for Binary Mixtures of Long-Chain Alcohols of 1-Hexanol + 1-Pentanol, + 2-Pentanol, + 2-Methyl-1-butanol, + 1-Heptanol, and + 1-Octanol from 288.15 to 338.15 K

Densities and viscosities for binary mixtures of long-chain alcohols are important to design transfer heat and mass equipment and to interpret the kind of interactions that occur in the studied blends. Current investigation indicated the measurements of densities and viscosities for liquid mixtures of 1-hexanol + 1-pentanol, + 2-pentanol, + 2-methyl-1-butanol, + 1-heptanol, and + 1-octanol from 288.15 to 338.15 K at atmospheric pressure and over the whole range of mole fractions. A vibrating tube densimeter and a glass capillary viscometer were used to measure the density and viscosity of the alcohol binary mixtures, respectively. Experimental measurements of the pure alcohols have been compared with the data reported in the literature using average absolute percentage deviation (AAPD) as a criterion. The obtained results demonstrated for density an AAPD of 0.023% and for viscosity an AAPD of 0.597%, which is a good agreement between the experimental findings and literature data. Excess molar volume and viscosity deviation present negative deviations for all the alcohol mixtures at the conditions considered in this research. These results indicate that the mixture suffers a volume contraction, which is caused by intermolecular forces of attraction between different alcohol molecules. The Redlich–Kister equation is used to fit the excess molar volume and viscosity deviation. Kinematic viscosities of the binary blends have been calculated through the Nava-Ríos et al. and McAllister equations.

Thermodynamic study of binary mixtures of propilophenone + 2-propanol, 2-butanol, 2-pentanol, or 2-hexanol at temperatures of 293.15 to 323.15 K: Modeling by Prigogine-Flory-Patterson theory

In the present work, the density and viscosity of binary mixtures of propiophenone (PP) + 2-propanol, PP + 2-butanol, PP + 2-pentanol, or PP + 2-hehanol were measured over all composition range and in the temperature range of 293.15 to 323.15 K at ambient pressure (0.1 MPa). Using the experimental data of density and viscosity, the excess molar volume and viscosity deviation were calculated and correlated by applying the Redlich-Kister equation. The results show that the excess molar volume of all mixtures is negative over the entire composition range at all temperatures and become more negative with increasing temperature. Also, the viscosity deviation of all mixtures is negative over the whole composition range at all temperatures and become less negative with increasing temperature. The excess molar volumes of mixtures were correlated by using Prigogine-Flory-Patterson (PFP) theory and the agreement between the calculated values with experimental data is good.

Thermodynamic, transport and spectral studies (FTIR) for some binary liquid mixtures of morpholine with isopropyl acetate, N-methylformamide and 2-propanol at various temperatures

ABSTRACT Densities, speeds of sound and viscosities of binary mixtures of morpholine with isopropylacetate, N-methylformamide and 2-propanol including those of pure liquids, over the entire composition range were measured at various temperatures (303.15, 308.15 and 313.15) K and 0.1MPa. Using the experimental data, the excess volume, excess isentropic compressibility, deviation in viscosity, excess partial properties of the components at infinite dilution were calculated. Finally, the Prigogine-Flory-Patterson (PFP) Theory is applied to identify the most predominant molecular interaction. Jouyban Acree model was used to correlate the experimental values of density, speed of sound and viscosity. Further binary mixing and FT-IR spectra were studied at equimolar concentration. From these results, the nature of interaction has been discussed in terms of intermolecular interaction between the mixing components

Densities, viscosities, volumetric properties and intermolecular interactions of binary mixtures of 1-ethyl-2,3-dimethylimidazolium tetrafluoroborate with three solvents

Densities and viscosities of binary mixtures of 1-ethyl-2,3-dimethylimidazolium tetrafluoroborate [EDMIM][BF4] with methanol, acetonitrile and acetone at 293.15 to 333.15 K were studied in this work. Volumetric properties including the apparent molar volume, the excess molar volume, the partial molar volume and the excess partial molar volume were calculated from the density data. The empirical linear formula was used to correlate the densities of the binary systems, and the apparent molar volumes and the viscosity were fitted with the Pitzer model and the Erying dynamic equation, respectively. Finally, the COSMO-RS model was adopted to analyze the interaction mechanism at the molecular level.

Volumetric, acoustic and viscometric properties of binary mixtures containing acetonitrile with glycols at several temperatures: Experimental study and correlations

Density, speed of sound and viscosity of binary mixtures of {acetonitrile + ethylene glycol (EG), or + diethylene glycol (DEG), or + triethylene glycol (TEG)} have been measured as a function of compositions at temperatures of 288.15, 293.15, 298.15 and 303.15 K and under atmospheric pressure. Excess molar volume, partial molar volume, excess partial molar volume, deviation in isentropic compressibility and deviation in viscosity were determined and excess properties have been fitted to the Redlich-Kister equation. The empirical models developed by Grünberg-Nissan, Heric-Brewer, Katti-Chaudhary and Van der Wyk were used to correlate the experimental viscosity data. The excess molar volume was also used to test the applicability of the Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS).

Density, viscosity and excess properties of binary mixtures of ethylene glycol and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

Densities and viscosities of binary mixtures of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [bmim][NTf2], with ethylene glycol (EG) were measured at atmospheric pressure and from 293.15 K to 338.15 K with a step increment of 5 K. A first-order polynomial and Vogel-Fulcher-Tammann (VFT) equation were described using experimental values to estimate the densities and viscosities of the mixtures, respectively. The excess molar volume, viscosity, and Gibbs energy of activation for viscous flow have been calculated and fitted to the Redlich-Kister equation. Besides, the thermal expansion coefficients and partial and apparent molar volumes of [bmim][NTf2] and EG in their binary mixtures have been reported.

Thermodynamic modelling of density and viscosity data of binary mixtures of haloarenes with cyclohexane

ABSTRACT Densities (ρ) and dynamic viscosity () of the binary mixtures haloarenes (2-chlorotoluene (o-CT) or 4-chlorotoluene (p-CT) or 1,3-dichlorobenzene (m-DCB)) (1) + cyclohexane (2) were experimentally measured at T = (298.15–318.15) K and atmospheric pressure. The excess molar volume and deviation in dynamic viscosity were calculated using ρ and data. The values for o-CT or p-CT or m-DCB (1) + cyclohexane (2) are negative at all compositions. The is a temperature dependent property. The values decreases as temperature rise. The values were analysed using Prigogine-Flory-Patterson (PFP) theory too. The values are negative at all compositions. The viscosity increases with the rise in temperature because of the opening of interstitial voids in mixture. Singh equation and Bloomfield and Dewan (BFD) model were applied to predict and values. The viscosities of binary mixtures have been predicted using different correlations.

Feedforward and cascade forward networks for viscosity prediction for binary mixtures of ammonium-based ionic liquids and water

Ionic liquids have been attracting great interest due to some properties, such as low vapor pressure, thermal and chemical stability, non-flammability and the possibility of designing ionic liquids for specific purposes. The development of new processes and the substitution of traditionally used solvents, however, depend on the availability of data for the substances involved, either experimental or modeling data. Neural networks are robust models that can be used for optimization, pattern classification and recognition, property prediction and many other applications. They can use experimental data to, after enough training, learn functional relationships between variables and then generalize them for unseen cases. In this work, neural networks were trained and applied in the prediction of viscosity for binary mixtures of ammonium-based ionic liquids and water using a group contribution approach. The input variables were the temperature, the ionic liquid mass fraction and the amount of each group used to describe the ionic liquids structures. The influence of the hidden neuron number and the addition of an extra hidden layer was investigated. Furthermore, 13 training algorithms were tested. Feedforward and cascade forward networks were compared. The average absolute relative deviations for the testing set varied from almost 200% to 0.1999% depending on the selected parameters. The results showed neural networks can be used successfully to predict viscosity data, but a careful selection of architecture and training algorithm is required.

VISCOMETRIC STUDY ON BINARY LIQUID MIXTURES OF PROPIOPHENONE WITH ANILINE AND N-ALKYL SUBSTITUTED ANILINES, AT 303.15 TO 318.15 K

Densities and viscosities of binary mixtures of Propiophenone with Aniline, N-methylaniline, N, N- dimethylaniline, N, N- diethylaniline were measured over the entire composition range at T = (303.15 to 318.15) K (with 5K interval) and atmospheric pressure. Experimental data were used to calculate the deviation of viscosity Δη, excess Gibb’s free energy G*E activation of viscous flow for each binary system, and these excess thermodynamic properties were fitted to the Redlich-Kister polynomial equation to obtain the fitting coefficients and standard deviations. McAllister’s three-body /four-body interaction models were used for the correlation of viscosity data. The studied systems exhibit good intermolecular interactions due to hydrogen ion transfer and charge dispersion in the carbonyl group and NH2 groups of Aniline and Alkyl Substituted Anilines. Experimental results are useful in various pharmaceutical industries.

Viscometric Properties of Binary Mixtures of 1,4-Butanediol + Cresols at Different Temperatures

The viscosities of binary mixtures of 1,4-butanediol with o-cresol, m-cresol and p-cresol have been determined at 303.15, 308.15, 313.15 and 318.15 K over the entire mole fraction range. The deviation in viscosity,, and excess Gibbs energy of activation (G*E) of viscous flow have been examined in terms of structural changes and interactions. The deviations/excess values were fitted to the Redlich-Kister equation to determine the fitting parameters and the root-mean square deviations. The results obtained for viscosity of binary mixtures were used to test the semi-empirical relations of Bingham, Frenkel, Kendall, HindUbbelhode, Refutas, Sutherland Wassiljiewa, Gambill, McAllister, Hind, Grunberg, Wijk, McAllister 4 body, Tamura Kurata, Katti-Chaudhri and Nhaesi.