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Inthis work experimental vapor–liquid equilibrium (VLE)data and three-phase vapor–liquid–liquid equilibrium(VLLE) data are presented for the carbon dioxide 1-decanol system.The VLE data were measured at five temperatures, (303.2, 308.2, 323.2,333.2, and 343.2) K, and pressures up to 16 MPa. The VLLE data coverpressure–temperature (P–T) values from289 K and 5 MPa to the upper critical end point (UCEP). We have usedtwo models to represent the complex fluid phase behavior (P–Tcritical curve, VLLE line, and VLE isotherms)of the carbon dioxide 1-decanol system: the cubic general equationof state (GEOS) and Peng–Robinson (PR) equation in conjunctionwith van der Waals two parameters conventional mixing rules (2PCMR).A correlation method involving temperature-dependent interaction parametersand a semipredictive approach with independent temperature interactionparameters have been used. Comparisons with experimental data reportedin this work and available in the literature indicate that the topologyof fluid phase behavior is satisfactorily given by the semipredictiveprocedure both for the critical line and in subcritical region, consideringthe relative simple used cubic equations of state. [ABSTRACT FROM AUTHOR]

Enzymaticalcoholysis of fish oil can produce monoacylglycerolsrich in polyunsaturated fatty acids at atmospheric pressure and lowtemperature. Biocatalysis in organic solvents helps to create a homogeneousreaction system for the reactants, ethanol and fish oil. This workpresents liquid–liquid equilibrium at two different temperatures(303.2 K and 323.2 K) and at atmospheric pressure for two solvent-systemsin the ethanolysis of fish oil: ethanol oil tert-pentanol and ethanol oil hexane. Experimental solubility (binodal)curves were obtained by the cloud point method and tie-line compositionwas obtained by density and high-temperature gas chromatography. Theconsistency of experimental tie-line data was checked by using theOthmer–Tobias equation. The experimental liquid–liquiddata were correlated satisfactorily by the nonrandom two liquid modelfor activity coefficient calculations. [ABSTRACT FROM AUTHOR]

The polarity of the ionic liquids [N4111][Tf2N], [N4441][Tf2N], and [choline][Tf2N], as well as their binary mixtures with ethanol has beeninvestigatedusing solvatochromic dyes and expressed in terms of the Reichardtparameter, ETN, and the Kamlet–Taft parameters (π*,α, and β), at 298.15 K. The synergetic behavior revealedessentially by the ethanol [N4441][Tf2N] systemfor the acidity of the solvent shows the potential importance of thissolvent media for some chemical applications. Even though the preferentialsolvation model of Bosch and co-workers has been applied with somestatistical success to the whole composition range of EtOH [N4111][Tf2N] and EtOH [N4441][Tf2N] binary mixtures, the interpretation of the results is somehowdifficult due to the competition of molecular interactions in theevaluation of transition energies for the pairs: dye–solvent(dye–cation and/or dye–anion, dye–EtOH, dye–complexentity) and cation–anion, depending on the composition range.Different patterns of solvent polarity behavior are shown along theentire ionic liquid (IL) composition. [ABSTRACT FROM AUTHOR]

The paper reports the isothermal vapor–liquidequilibria(VLE) of five binary mixtures containing 2-butanol heptane, 2,2,4-trimethylpentane, dodecane, cyclohexane, and methylbenzene at 313.15 K. A statictechnique has been used for the measurements. Data reduction by Barker'smethod provides the parameters of GEmodels.The six-parameter Margules equation, Wilson, nonrandom two-liquid(NRTL), and universal quasichemical activity coefficient (UNIQUAC)models have been used for the correlation of the experimental data.Good results have been obtained for all. The five investigated mixturesexhibit a positive deviation from ideality, and four of them showa maximum pressure azeotrope. Only the mixture 2-butanol dodecanedoes not present an azeotrope. [ABSTRACT FROM AUTHOR]

Liquid–liquid equilibrium (LLE) data are presentedfor ammoniumbased ionic liquids (ILs) dibenzothiophene (DBT) n-dodecane at 298.2 K and atmospheric pressure (∼95 kPa). Molefractions were determined by the refractometry or graphical method.DBT phase distribution, ionic liquid selectivity, and DBT percentextraction were determined. Ionic liquids used here were comparedwith imidazolium in terms of sulfur removal. Hand and Othmer–Tobiascorrelations were used to test the LLE data and gave σ <0.09 (R2> 0.90). The nonrandom two-liquidmodel (NRTL) was used to correlate the LLE data, giving percent root-mean-squaredeviations < 0.22 between experimental and calculated mole fractions. [ABSTRACT FROM AUTHOR]

Experimental results are reported for the solubility of carbon dioxide in liquid mixtures of water and the ionic liquid 1-n-butyl-3-methylimidazolium methylsulfate ([bmim][CH3SO4]). Three (gas-free) solvent compositions were considered with mass fractions of [bmim][CH3SO4] of w′ ≈ 0.15, 0.50, and 0.87 (mole fractions x′ ≈ 0.013, 0.066, and 0.33). In the isothermal experimental series, the temperature was about (293, 333, and 373) K. The total pressure ranged up to about 10 MPa. The molality of carbon dioxide in the solvent mixture of (water [bmim][CH3SO4]) (the mole fraction of carbon dioxide in the liquid) ranged up to approximately 1.64 mol·kg–1(about 0.0332). The experimental results are used to determine Henry's constant of carbon dioxide in the liquid mixtures of (water [bmim][CH3SO4]) as well as the partial molar volume of that gas at infinite dilution in those solvent mixtures. The phase equilibrium is described by applying an extension (to solvent mixtures) of Pitzer's molality scale-based equation for the Gibbs excess energy. [ABSTRACT FROM AUTHOR]

The surface tension of (2-methyl-2-butanol ethanol), (3-methyl-1-butanol ethanol), and (2-methyl-1-butanol ethanol) binary solutions was measured over the entire composition range and at temperatures from (293.15 to 323.15) K. The experimental data were correlated with the temperature, the maximum deviation being less than 0.4 %. [ABSTRACT FROM AUTHOR]

The solubility of solid bisphenol A (4,4′-(propane-2,2-diyl)diphenol) in supercritical carbon dioxide (SC-CO2) has been measured at temperatures of T= 313 K, T= 333 K, and T= 353 K and in the pressure range 12 MPa < P< 20 MPa, using a variable-volume view cell according to the synthetic method. The solubility increases with increasing pressure and temperature, ranging from 1.8·10–5(mole fraction) at T= 313 K and P= 16.4 MPa to 7.7·10–5(mole fraction) at T= 353 K and P= 14.6 MPa. The solubility data obtained have been correlated using the Peng–Robinson equation of state with quadratic mixing rules. The results obtained are useful for the design of processes for the synthesis or recycling of polycarbonate in supercritical CO2. [ABSTRACT FROM AUTHOR]

Experimental results have been obtained for the equilibrium liquid−vapor surface tension of the binary system composed of water polyvinylpirrolidone (PVP). In this work we studied two different samples of PVP, at concentrations of (0.000002, 0.000018, 0.000102, 0.000499, 0.000999, 0.002003, 0.003018, 0.004021, and 0.005111) mass fraction of the polymer, at (288.15, 293.15, 298.15, and 303.15) K. The density has also been determined experimentally, for the same aqueous solutions in the same temperature range studied of surface tension, using two Anton Paar vibrating-tube densimeters (models DMA 60 and DMA 4500M). The values of the surface tension of the binary system decrease as the PVP concentration increases and as the temperature increases. The surface tension results of the binary system were correlated simultaneously as a function of temperature and PVP concentration. From the density results, the partial molar volume and the infinite dilution partial molar volume of the polymer have been calculated, which were correlated successfully with a general equation which takes into account the influence of the polymer concentration and temperature. [ABSTRACT FROM AUTHOR]