Excess Volumes Of Binary Mixtures Research Articles

Measurement of VLE Data by Using an Experimental Installation with Automatic Control: Modeling of Binary Systems of Methyl Acetate or Ethyl Acetate with n-Heptane or 2,2,4-Trimethylpentane at Both 0.1 and 1.5 MPa

The excess volume of binary mixtures and the isobaric vapor–liquid equilibrium (VLE) data at high pressure have been determined. The VLE values for methyl acetate + n-heptane or 2,2,4-trimethylpent...

Excess Volume of Binary Mixtures of Water (Methanol or Ethanol) with an Ionic Liquid [EEIM][DEP] or [BEIM][DEP] at 1 atm and (293.15 to 333.15) K

Densities were measured for the binary mixtures of water (methanol or ethanol) and an ionic liquid (IL) 1,3-diethylimidazolium diethylphosphate [EEIM][DEP] or 1-n-butyl-3-ethylimidazolium diethylphosphate [BEIM][DEP] at 1 atm and (293.15 to 333.15) K using a vibrating-tube densimeter. The molecular volume, standard entropy, and lattice energy of the two ILs were estimated with the Glasser theory. The excess volumes are negative for all binary mixtures studied in the whole composition range, and reach to the maximum at the mole fraction of IL being around 0.3. Besides, they decrease with increasing temperature for the aqueous solution of ILs, whilst a reverse trend is found for the IL solutions of methanol or ethanol at any concentration. The excess molar volumes were correlated successfully by a five-parameter polynomial equation as a function of temperature and mole fraction of IL with average absolute relative deviation (ARD) of density within 0.02%.

Volumetric Properties of Propane, n-Octane, and Their Binary Mixtures at High Pressures

Density, isothermal compressibility, isobaric expansivity, thermal pressure coefficient, and excess volumes for binary mixtures of propane + n-octane are reported over a wide range of temperatures (from 320 to 440 K), and pressures (up to 400 bar) for mixture compositions with 0, 20.4, 42.4, 58.9, 79.7, and 100 wt % propane. Densities were determined using a fully computerized variable-volume view-cell system. A motorized pressure generator is used to bring about changes in the position of a movable piston in the cell at controlled and adjustable rates thereby bringing about changes in the internal volume and thus pressure. A long stroke-length linear variable differential transformer is used to continually monitor the position of the piston and thus the cell volume in real-time. Knowing the initial loading of the cell and the cell volume at any moment as pressure is altered permits generation of continuous density profiles along pressure scans in increasing (compression) or decreasing (decompression) dir...

Density, Speed of Sound, Isentropic Compressibility, and Excess Volume of Binary Mixtures of 1-Amino-2-propanol or 3-Amino-1-propanol with 2-Amino-2-methyl-1-propanol, Diethanolamine, or Triethanolamine from (293.15 to 323.15) K

Density and speed of sound binary mixtures of 1-amino-2-propanol (MIPA) or 3-amino-1-propanol (AP) with 2-amino-1-methyl-1-propanol (AMP), diethanolamine (DEA), or triethanolamine (TEA) were measured over the entire composition range and at temperatures from (293.15 to 323.15) K. The experimental values were used to calculate the isentropic compressibilities, excess molar volumes, and isentropic compressibility deviations. Redlich−Kister type polynomial equations were used to fit the excess molar volumes and isentropic compressibility deviations.

Densities and excess volumes of binary mixtures of N, N-dimethylformamide with aromatic hydrocarbon at different temperature

Density of three binary mixtures formed by N, N-dimethylformamide (DMF) with aromatic hydrocarbon (one of benzene, toluene, and ethylbenzene) has been determined over the full range of compositions at the temperatures range (293.15 to 353.15) K and atmospheric pressure using a vibrating-tube densimeter. From these experiments, excess molar volumes ( V m E ) could be calculated and fitted by the fourth-order Redlich–Kister equation, so the coefficients and the standard error ( σ) could be got. Our result shows V m E decreases when temperature increases in the studied systems.

Densities and excess volumes of binary mixtures of the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate with aromatic compound at T = (298.15 to 313.15) K

The density of two binary mixtures formed by 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6] with aromatic compound (benzyl alcohol or benzaldehyde) has been determined over the full range of compositions at the temperature range from 298.15 K to 313.15 K and at atmospheric pressure using a vibrating-tube densimeter (DMA4500). Excess molar volumes ( V m E ) have been obtained from these experimental results, and been fitted by the fourth-order Redlich–Kister equation. Our results show V m E decreases slightly when temperature increases in the systems studied. The results have been interpreted in terms of ion–dipole interactions and structural factors of the ionic liquid and these organic molecular liquids.

Volumetric and refractive properties of binary mixtures containing 1,3-dioxolane and isomeric chlorobutanes

The relation between refractive index deviations and excess volumes for binary mixtures formed by a cyclic ether and a haloalkane has been tested using several methods: refractive index mixing rules and equations of state. Refractive index deviations, excess volumes and molar refractions have been calculated from experimental data of refractive indices and densities at two temperatures 298.15 and 313.15 K. Results obtained have been discussed in terms of intermolecular interactions. Refractive indices were compared with those predicted by several mixing rules. Excess volumes have also been correlated using several cubic equations of state and finally a relation between parameter b from equations of state and molar refraction has been provided.

Excess volume of polymer/solvent mixtures and proposed model for prediction of activity of solvents based on excess volume data

Density measurements were used to evaluate the excess volume of binary mixtures of poly(ethylene glycol) in water and ethanol solvents, poly(propylene glycol) in water and ethanol solvents, and poly(vinyl alcohol) in water solvent at different temperatures for various molecular weights of polymers. The excess volumes were correlated and expressed by a polynomial in terms of the weight fraction of the polymer. The activity of the solvent was expressed in terms of three parts: excess internal energy, excess entropy, and excess volume. The excess volume was derived from the expression obtained in this work, the excess entropy was derived from Flory's lattice model, and the excess internal energy was used as a weight average of the excess volume and entropy parts. The results indicated good agreement between the activity of the solvent calculated by the proposed model and the experimental data. The proposed model has the advantage that using only simple density measurements the activity values that are necessary in the calculation of thermodynamic properties can be evaluated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1219–1227, 2005

Experimental Densities and Excess Volumes for Binary Mixtures Containing Propionic Acid, Acetone, and Water from 283.15 K to 323.15 K at Atmospheric Pressure

Experimental Densities and Excess Volumes for Binary Mixtures Containing Propionic Acid, Acetone, and Water from 283.15 K to 323.15 K at Atmospheric Pressure

Experimental densities and excess volumes for binary mixtures of (dimethyl sulfoxide + an aromatic hydrocarbon) at temperatures from (293.15 to 353.15) K at atmospheric pressure

Experimental data on density of (dimethyl sulfoxide + benzene, or toluene, or ethylbenzene, or styrene) were obtained at temperatures (293.15, 303.15, 313.15, 323.15, 333.15, 343.15, 353.15) K and atmospheric pressure by means of a vibrating-tube densimeter. From these data, excess molar volume has been calculated. The computed quantities have been fitted to the fourth-order Redlich–Kister equation to derive the coefficients and estimate the standard error values. It was found that the V m E in the systems studied increases with rising temperature.

Experimental Densities and Excess Volumes for Binary Mixtures Containing Propionic Acid, Acetone, and Water from 283.15 K to 323.15 K at Atmospheric Pressure

We present experimental density measurements for the binary systems acetone + water, propionic acid + water, and acetone + propionic acid from 283.15 K to 323.15 K over the entire composition range. A vibrating tube densimeter produced the experimental densities. We have also calculated excess volumes and correlated them with a Redlich−Kister polynomial form.

Densities and excess volumes of binary mixtures of 1,4-dioxane with either ethyl acrylate, or butyl acrylate, or methyl methacrylate, or styrene at T=298.15 K

Densities of binary mixtures of 1,4-dioxane with either ethyl acrylate, or butyl acrylate, or methyl methacrylate, or styrene have been measured as a function of composition at T=298.15 K and atmospheric pressure with an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess volumes were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. The excess volumes are positive for the mixtures of 1,4-dioxane with methyl methacrylate and butyl acrylate and negative for the mixtures of 1,4-dioxane and styrene. The excess volumes for the system 1,4-dioxane and ethyl acrylate are negative for mole fractions x of 1,4-dioxane less than or equal to about 0.44 and positive at x greater than about 0.4498 and positive thereafter.

Excess enthalpies and excess volumes of binary mixtures of hydrofluoroether with alcohols

Excess enthalpies and excess volumes of { x nonaflluorobutylmethylether + ( 1 −x) ethanol or methanol} were measured at T= 298.15 K. Excess enthalpies of both mixtures are positive and flatten in the middle mole fraction because of the concentration fluctuation approaching phase separation. Excess volumes were also large and flatten in the middle mole fraction. Partial molar enthalpies of ethanol or methanol are very large at infinite dilution in comparison with those of nonafluorobutylmethylether because of the breaking of hydrogen bonds of alcohol on mixing. The strong hydrogen bonds of methanol depresses the partial molar volume of methanol at infinite dilution.

Excess volumes of binary mixtures of vinyl acetate and aromatic hydrocarbons

Excess molar volumes of (vinyl acetate + toluene, or ethylbenzene, orp -xylene, or isopropylbenzene, or butylbenzene, or isobutylbenzene, or mesitylene, or t -butylbenzene), were determined from density measurements at T= 298.15 K using a vibrating-tube densimeter. The excess molar volumes are positive over the whole composition range, and increase with the size of the hydrocarbon. Steric hindrance in these mixtures was investigated in terms of the partial excess molar volumes behaviour. The experimental data were used to determine the binary interaction parameters of the Soave–Redlich–Kwong (SRK) equation of state for use in multicomponent excess functions calculations.

Excess Volumes of Binary Mixtures of Benzene + 1-Alkanols at 303.15 K

Excess molar volumes VE of binary mixtures of benzene + 1-propanol, + 1-butanol, + 1-pentanol, + 1-hexanol, + 1-heptanol, + 1-octanol, + 1-nonanol and 1-decanol were measured at 303.15 K. The VE values are positive over the entire range of composition for these mixtures. The results are discussed in terms of intermolecular interactions.

Excess volumes of binary mixtures that contain olive oil with alkyl and vinyl acetates

AbstractThis paper reports densities and excess molar volumes for ethyl acetate, vinyl acetate, propyl acetate, isopropyl acetate, and butyl acetate with olive oil at temperatures from 283.15–298.15 K. Redlich‐Kister polynomials were fitted to the results of excess volumes. All the systems showed slight deviations from ideality. The excess volumes decreased with the number of carbon atoms of the acetate, but increased with an increase of temperature.

Speeds of Sound, Isentropic Compressibilities, and Excess Volumes of Binary Mixtures of Acrylonitrile with Organic Solvents

The isentropic compressibilities KS, excess isentropic compressibilities , and excess molar volumes VE have been determined from the measurements of speeds of sound u and densities ρ of seven binary mixtures of acrylonitrile with ethanenitrile, methyl acetate, ethyl acetate, n-butyl acetate, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide at 303.15 K. Variable-degree polynomials were fitted to the results. The values of the excess functions indicate a varying extent of molecular interaction and interstitial accommodation between unlike components. The experimental speeds of sound have been analyzed in terms of the collision factor theory of Schaaffs (Molekularakustik; Springer-Verlag: Berlin, 1963) and the free length theory of Jacobson (Acta Chem. Scand. A 1952, 6, 1485−1498).

Excess volumes of binary mixtures containing polyhaloalkanes at the temperatureT=298.15 K

Excess molar volumesVmEof {xBr2CH2+(1−x) (BrCH2Cl, or BrCCl3, or FCl2CCF2Cl)}, or {xBrCH2Cl+(1−x) (BrCCl3or FCl2CCF2Cl)}, {xBrCCl3+(1−x) FCl2CCF2Cl}, and {xCl3CF+(1−x) (BrCCl3, or FCl2CCF2Cl)} have been determined from density measurements at the temperature 298.15 K and atmospheric pressure using a vibrating-tube densimeter. The excess molar volumesVmEfor these mixtures are positive except for {xBrCCl3+(1−x)Cl3CF}.

Excess Volumes for Binary Mixtures Formed by Methyl Acetate with Aromatic Hydrocarbons

Excess molar volumes for binary mixtures containing methyl acetate + methylbenzene, ethylbenzene, 1,4-dimethylethylbenzene, 1-methylbenzene, 1,-3,-5-trimethylbenzene or 1,-1-dimethylethylbenzene were determined from density measurements at 298. 15 K using an Anton Paar DMA 58 vibrating tube densitometer. The excess molar volumes were positive throughout the concentration ranges. The excess molar volumes increase with the size of the hydrocarbon.

Excess Volumes of Binary Mixtures Containing Diisopropyl Ether + 1-Butanol or Diisopropyl Ether + Diethyl Ketone and Ethanol + Heptane at High Pressures

Excess molar volumes VE of diisopropyl ether with 1-butanol were measured at pressures of 0.1 MPa, 20 MPa, 40 MPa, and 60 MPa and at temperatures of 278.15 K, 298.15 K, and 323.15 K; mixtures of diisopropyl ether + diethyl ketone, at 278.15 and 298.15 K. VE is negative for all the mixtures studied over the whole concentration range and for all temperatures. Excess molar volumes VE of ethanol with heptane were measured at 298.15 K and 0.1 MPa, 20 MPa, and 60 MPa. VE is positive in all mixtures studied. Results were correlated by polynomial equations of the type VE = x1x2∑iAi(2x1 − 1)i.