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1.
《Fluid Phase Equilibria》1998,152(2):255-263
Isothermal vapor–liquid equilibria (VLE) for mixtures containing 1,1,1-trichloroethane+tetrahydrofuran+propan-2-ol have been measured using a modified version of a Boublik–Benson still at 298.15 K. A test of thermodynamic consistency, like McDermott–Ellis method was applied to the activity coefficients. Excess molar Gibbs free energies were calculated over the entire range composition. Different expressions existing in the literature were used to predict the activity coefficients. 相似文献
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An approach is presented to calculate solid–liquid phase equilibrium for binary mixtures, using expressions for the temperature as a function of the molar fraction. For Margules model the expression gives explicitly the temperature, while for other liquid phase activity models an iterative procedure is required to calculate the temperature. The method is very easy to apply and it can be used for mixtures that have peritectic and eutectic points, or just a eutectic point. The approach was applied to five case studies with binary mixtures of fatty acids and triglycerides. The results were in good agreement with experimental data. 相似文献
4.
R. Trabelsi Shaik Babu H. Salhi N. Ouerfelli A. Toumi 《Physics and Chemistry of Liquids》2018,56(6):801-815
Excess molar volumes and refractive index, molar refraction deviations and isentropic compressibility changes in 1,4-dioxane + isobutyric acid binary mixtures (from 295.15 to 313.15) K. were calculated from experimental density, refractive index and sound velocity data presented in previous work. Here, these experimental values were used to test the applicability of the correlative reduced Redlich–Kister equation as well as their corresponding relative functions which are important to reduce the effect of temperature and, consequently, to reveal the effects of different types of interactions. The results of these observations have been interpreted in terms of structural effects of the solvents. The correlating equation recently proposed by Belda, has also been applied to the present system in order to assess the validity of this equation and to give thermodynamic limiting partial molar quantities interesting to evaluate solute–solvent interaction. 相似文献
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《Physics and Chemistry of Liquids》2012,50(3):346-366
Knowledge and prediction of physicochemical properties of binary mixtures is of great importance for understanding intermolecular interactions. The literature shows that most such systems exhibit non-linear behaviour. Excess molar volumes, viscosity deviations and isentropic compressibility changes in N,N-dimethylacetamide?+?2-methoxyethanol binary mixtures at 298.15, 308.15 and 318.15?K were calculated from experimental density, viscosity and sound velocity data presented in previous work. Here these experimental values were used to test the applicability of the correlative reduced Redlich–Kister equation and the recently proposed Herráez equation as well as their corresponding relative functions. Their correlation ability at different temperatures, and the use of different numbers of parameters, is discussed for the case of limited experimental data. These relative functions are important to reduce the effect of temperature and, consequently, to reveal the effects of different types of interactions. Limiting excess partial molar volume at infinite dilution were deduced from different methods, activation parameters and partial molar Gibbs energy of activation of viscous flow against compositions were investigated. The results of these observations have been interpreted in terms of structural effects of the solvents. In this frame, a correlating equation is recently proposed by Belda and in order to assess the validity of the proposed equation, it has also been applied to the present system for molar volume properties. 相似文献
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《Fluid Phase Equilibria》2002,202(1):29-47
Isothermal vapor–liquid equilibrium (VLE) data for the propane+1,1,1,2,3,3,3-heptafluoropropane (R227ea) binary system were measured at 293.16, 303.14, 313.14, 333.15, 343.16 and 353.18 K and pressures up to 3.5 MPa. The experimental method, used in this work, is of the static-analytic type. It takes advantage of two pneumatic capillary samplers (Rolsi™, Armines’ patent) developed in the Cenerg/TEP laboratory. The peculiarity of R227ea–propane binary system is to present azeotropic behavior at each studied temperature.The six sets of isothermal P, x, y data are represented with the Soave–Redlich–Kwong (SRK) equation of state (EoS) and several mixing rules involving the NRTL model. 相似文献
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《Fluid Phase Equilibria》2004,218(1):95-101
Isothermal vapor–liquid equilibrium (VLE) data have been measured for the binary system carbon dioxide (CO2)+difluoromethane(R32) at eight temperatures between 283.12 and 343.25 K, and at pressures in the range 1.11–7.46 MPa. The experimental method used in this work is of the static-analytic type, taking advantage of two pneumatic capillary samplers (Rolsi™, Armines’ Patent) developed in the Cenerg/TEP laboratory. The data were obtained with uncertainties within ±0.02 K, ±0.002 MPa, and ±1% for molar compositions. The isothermal P, x, and y data are well represented with the Peng–Robinson equation of state (PR EoS) using the Mathias Copeman alpha function and the Wong–Sandler mixing rules involving the NRTL model. 相似文献
8.
Vapor–liquid equilibrium data for the binary systems of carbon monoxide (CO) + diethyl carbonate (DEC) and carbon monoxide + ethyl acetate (EA) were measured at temperatures of 293.2 K, 313.2 K and 333.2 K and the elevated pressures up to 12.00 MPa. The measurements were carried out in a cylindrical autoclave with a moveable piston and an observation window. The experimental data were correlated using the Peng–Robisom (PR) equation of state (EOS) and Peng–Robinson–Stryjek–Vera (PRSV) equation of state with the two-parameter van der Waals II or Panagiotopoulos–Reid mixing rule. The interaction parameters were obtained while correlating. The comparison between calculation results and experimental data indicated that the method of PRSV equation of state with van der Waals II produced the better correlated results. 相似文献
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《Fluid Phase Equilibria》1999,166(2):225-236
A new apparatus designed for the study of vapour–liquid equilibria (VLE) of small molecules at temperatures down to 77 K and pressures up to 40 MPa was built, set-up and used up to 2.8 MPa. It is based on the `static-analytic' method using two pneumatic capillary sampling devices, which allow taking small and reliable in-situ samples and performing direct analyses through gas chromatography. Accurate P, x, y isothermal data obtained for the O2–N2 and Ar–N2 mixtures are well represented by the Soave–Redlich–Kwong equation of state (SRK-EoS). The conclusions which can be drawn from the comparison with literature data are the following: maximum deviations on pressure, temperature and vapour phase composition, between literature experimental data and the calculated ones (using our binary interaction parameters) are not larger than 3.3%, 0.12 K and 4.2%. We also point out inconsistencies in several literature data. 相似文献
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Shaik Babu Radhia Trabelsi Tadikonda Srinivasa Krishna Noureddine Ouerfelli Adel Toumi 《Physics and Chemistry of Liquids》2019,57(4):536-546
In order to understand the effect of different types of interactions in liquid mixtures by applying the correlative reduced Redlich–Kister equation, excess molar volume, excess dielectric constant, deviation in refractive index, deviation in molar refraction and molar polarisation were calculated at the temperature 298.15 K and atmospheric pressure P = 101.325 kPa for the binary mixture Petrofin (1) + Dehpa (2). The experimentally determined data of density and refractive index which were published earlier were used for these calculations. The results were interpreted in terms of structural effects of the solvents. 相似文献
12.
《Physics and Chemistry of Liquids》2012,50(3):275-285
Experimental data of vapour–liquid equilibrium (VLE) for the binary systems tetrahydrofuran, or tetrahydropyran, or 2-methyl-tetrahydrofuran, or 2,5-dimethyl-tetrahydrofuran with bromocyclohexane have been measured in isobaric conditions at two pressures, 40.0 and 101.3?kPa. The equipment used was a dynamic recirculating still. The consistency of the measured VLE data has been tested with the Van Ness’ point-to-point method. The activity coefficients have been correlated with the mole fraction through Wilson, NRTL and UNIQUAC equations. 相似文献
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Isothermal vapor–liquid equilibrium data at 333.15 K are measured for the binary system ethanol + 2,2,4-trimethylpentane and for ternary system di-methyl carbonate (DMC) + ethanol + 2,2,4-trimethylpentane by using headspace gas chromatography. The experimental binary and ternary vapor–liquid equilibrium data were correlated with different activity coefficient models. Excess volume and deviations in molar refractivity data are also reported for the binary systems DMC + ethanol and DMC + 2,2,4-trimethylpentane and the ternary system DMC + ethanol + 2,2,4-trimethylpentane at 298.15 K. These data were correlated with the Redlich-Kister equation for the binary systems and the Cibulka equation for the ternary system, respectively. The ternary excess volume and deviations in molar refractivity data were also compared with estimated values from the binary contribution models of Tsao–Smith, Kohler, Rastogi and Radojkovi?. 相似文献
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Qin Wang Ying-Jie XuZan-Jun Gao Yu QiuXu-Wei Min Xiao-Hong HanGuang-Ming Chen 《Fluid Phase Equilibria》2010
Vapor–liquid equilibrium (VLE) data for the refrigerant mixture ethyl fluoride (HFC-161) + 1,1,1,2,3,3,3-heptafluoroproane (HFC-227ea) are reported in the temperature range from 253.15 K to 313.15 K with a single-phase circulation vapor–liquid equilibrium still. The results of the correlation for the vapor–liquid equilibrium data with Peng–Robinson (PR) equation of state (EOS), combined with the first Modified Huron-Vidal (MHV1) mixing rule and Wilson model, are presented. These results are in a good agreement with experimental data. The average and maximum derivations of vapor molar composition are within 0.0130 and 0.0295 respectively, and the average and maximum relative derivations of pressure are within 1.04% and 2.96%, respectively. The model parameters, determined from these binary data, are given to predict the phase behavior for a later ternary system. The binary system HFC-161 + HFC-227ea is a non-azeotropic mixture and exhibits a negative deviation from Raoult's law. 相似文献
15.
《Physics and Chemistry of Liquids》2012,50(6):535-541
The excess molar volume of the ternary mixture [2-propanol?+?ethyl acetate?+?n-hexane], and its binary constituents; [2-propanol?+?ethyl acetate], [2-propanol?+?n-hexane] and [ethyl acetate?+?n-hexane] were evaluated by the mixtures density measurements over the whole concentration range at three temperatures 298.15, 308.15 and 313.15?K. The excess molar volumes data were fitted to the Redlich–Kister (RK) type equation and the parameters of this equation have been calculated and presented for the studied mixtures. 相似文献
16.
《Fluid Phase Equilibria》1999,165(2):197-208
Experimental isothermal P–x data at 313.15 K for the ternary system (tert-amylmethyl ether (TAME)+n-heptane+methanol) and for one of the unmeasured constituent binary systems, (tert-amylmethyl ether (TAME)+methanol) are reported. Data reduction by Barker's method provides correlations for gE using the Margules equation for the binary systems and the Wohl expansion for the ternary system. Wilson, NRTL and UNIQUAC models have been applied successfully to both the binary and the ternary systems. The presence of azeotropes in the ternary system and constituent binaries are studied as well as the presence of immiscible zones. 相似文献
17.
《Fluid Phase Equilibria》2002,193(1-2):289-301
The experimental isothermal P–x data at T=313.15 K for the two ternary systems (isopropyl ether+n-heptane+1-hexene) and (1-hexene+n-heptane+benzene) are reported. Data reduction by Barker’s method provides correlation for GE. The Wohl expansion, also Wilson, NRTL and UNIQUAC models have been applied successfully to the ternary systems. The experimental data, in this work are not available in the literature. 相似文献
18.
《Physics and Chemistry of Liquids》2012,50(6):721-730
Calculation of excess properties in N,N-dimethylacetamide + 2-ethoxyethanol binary mixtures at (298.15, 308.15 and 318.15) K from experimental density, viscosity and sound velocity values were presented in previous work. Applications of these experimental values to test different correlation equations as well as their corresponding relative functions were also reported. Considering the quasi-equality between the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ?H*, here we can define partial molar activation energy Ea1 and Ea2 for N,N-dimethylacetamide and 2-ethoxyethanol, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all the domains of composition shows the existence of two main distinct behaviours separated by a stabilised structure in a short range of mole fraction in N,N-dimethylacetamide from 0.14 to 0.45. We add that correlation reveals interesting Arrhenius temperature, which is closely related to the vaporisation temperature in the liquid vapour equilibrium. 相似文献
19.
《Fluid Phase Equilibria》2004,217(2):157-164
Experimental isothermal P–x data at T=313.15 K for the binary systems 1,1-dimethylethyl methyl ether (MTBE)+n-hexane and methanol+n-hexane, and the ternary system MTBE+methanol+n-hexane are reported. Data reduction by Barker’s method provides correlations for GE using the Margules equation for the binary systems and the Wohl expansion for the ternary system. Wilson, NRTL and UNIQUAC models have been applied successfully to both the binary and the ternary systems. Moreover, we compare the experimental results for these binary mixtures to the prediction of the UNIFAC (Dortmund) model. Experimental results have been compared to predictions for the ternary system obtained from the Wilson, NRTL, UNIQUAC and UNIFAC models; for the ternary system, the UNIFAC predictions seem poor. The presence of azeotropes in the binary systems has been studied. 相似文献
20.
《Fluid Phase Equilibria》1998,152(2):243-254
Molar excess enthalpies, HE, at 303.15 K and atmospheric pressure, of n-propyl-, n-butyl-, n-pentyl-, n-octyl- or n-decylamine+toluene, as well as the isothermal vapour–liquid equilibria, VLE, of n-butylamine+toluene and of n-butylamine+benzene at 298.15 K have been determined. These experimental results, along with the data available in the literature on molar excess Gibbs energies, GE, activity coefficients at infinite dilution, γi∞, and molar excess enthalpies, HE, for n-alkylamine+toluene mixtures are examined on the basis of the DISQUAC group contribution model. The modified UNIFAC is also used to describe the mixtures. 相似文献