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1.
(p, ρ, T) properties were determined in liquid phase for 1-butanol and 2-butanol at temperatures from 313 K to 363 K and pressures up to 25 MPa using a vibrating tube densimeter. The uncertainty is estimated to be lower than ±0.2 kg · m−3 for the experimental densities. Nitrogen and water were used as reference fluids for the calibration of the vibrating tube densimeter. Experimental densities of 1-butanol and 2-butanol were correlated with a short empirical equation and the 11-parameter Benedict–Webb–Rubin–Starling equation of state (BWRS EoS) using a least square optimization. Statistical values to evaluate the different correlations were reported. Published densities of 1-butanol and 2-butanol are compared with values calculated with the BWRS EoS using the parameters obtained in this work. The experimental data determined here are also compared with available correlations for 1-butanol and 2-butanol.  相似文献   

2.
《Fluid Phase Equilibria》2002,201(2):401-407
Phase equilibria and saturated densities for ethane+1-butanol system at high pressures were measured using a static-circulation apparatus at 313.15 K. The experimental apparatus equipped with three Anton Paar DMA 512S vibrating tube density meters was previously developed for measuring vapor–liquid–liquid equilibrium (VLLE) at high pressures. Co-existing phase composition and saturated density of each phase can be measured by means of the apparatus with a maximum temperature and pressure of 400 K and 20 MPa, respectively. The present experimental results include vapor–liquid equilibria (VLE), liquid–liquid equilibria (LLE), and VLLE. The equilibrium composition and density of each phase were determined by gas chromatography and density measurements, respectively. The experimental data were correlated with various equations of state.  相似文献   

3.
(Liquid + liquid) equilibrium (LLE) data for {water + acrylic acid + (1-butanol, or 2-butanol, or 1-pentanol)} at T = 293.2 K, T = 303.2 K, and T = 313.2 K and atmospheric pressure (≈95 kPa) were determined by Karl Fischer titration and densimetry. All systems present type I binodal curves. The size of immiscibility region changes little with an increase in temperature, but increases according to the solvent, following the order: 2-butanol < 1-butanol < 1-pentanol. Values of solute distribution and solvent selectivities show that 1-pentanol is a better solvent than 1-butanol or 2-butanol for acrylic acid removal from water solutions. Quality of data was ascertain by Hand and Othmer-Tobias equations, giving R2 > 0.916, mass balance and accordance between tie lines and cloud points. The NRTL model was used to correlate experimental data, by estimating new energy parameters, with root mean square deviations below 0.0053 for all systems.  相似文献   

4.
(Liquid + liquid) equilibrium (LLE) and binodal curve data were determined for the systems (water + phenol + tert-butanol) at T = 298.15 K, (water + phenol + 2-butanol) and (water + phenol + 1-butanol) at T = 298.15 K and T = 313.15 K by the combined techniques of densimetry and refractometry. Type I curve (for tert-butanol) and Type II curves (for 1- and 2-butanol) were found. The data were correlated with the NRTL model and the parameters estimated present root mean square deviations below 2% for the system with tert-butanol and lower than 0.8% for the other systems.  相似文献   

5.
The experimental densities for the binary or ternary systems were determined at T = (298.15, 303.15, and 313.15) K. The ionic liquid methyl trioctylammonium bis(trifluoromethylsulfonyl)imide ([MOA]+[Tf2N]) was used for three of the five binary systems studied. The binary systems were ([MOA]+[Tf2N] + 2-propanol or 1-butanol or 2-butanol) and (1-butanol or 2-butanol + ethyl acetate). The ternary systems were {methyl trioctylammonium bis(trifluoromethylsulfonyl)imide + 2-propanol or 1-butanol or 2-butanol + ethyl acetate}. The binary and ternary excess molar volumes for the above systems were calculated from the experimental density values for each temperature. The Redlich–Kister smoothing polynomial was fitted to the binary excess molar volume data. Virial-Based Mixing Rules were used to correlate the binary excess molar volume data. The binary excess molar volume results showed both negative and positive values over the entire composition range for all the temperatures.The ternary excess molar volume data were successfully correlated with the Cibulka equation using the Redlich–Kister binary parameters.  相似文献   

6.
《Fluid Phase Equilibria》2006,239(2):156-160
(Liquid + liquid) equilibrium (LLE) data for (water-1-propanol-solvent) were measured at T = 298.2 K and atmospheric pressure. The solvents were methyl acetate, ethyl acetate and n-propyl acetate. The UNIQUAC and UNIFAC models were used to correlate the experimental data. A comparison of the extracting capabilities of the solvents was made with respect to distribution coefficients, separation factors.  相似文献   

7.
Henry’s law constants and infinite dilution activity coefficients of cis-2-butene, dimethylether, chloroethane, and 1,1-difluoroethane in methanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol in the temperature range of 250 K to 330 K were measured by a gas stripping method and partial molar excess enthalpies were calculated from the activity coefficients. A rigorous formula for evaluating the Henry’s law constants from the gas stripping measurements was used for the data reduction of these highly volatile mixtures. The uncertainty is about 2% for the Henry’s law constants and 3% for the estimated infinite dilution activity coefficients. In the evaluation of the infinite dilution activity coefficients, the nonideality of the solute such as the fugacity coefficient and Poynting correction factor cannot be neglected, especially at higher temperatures. The estimated uncertainty of the infinite dilution activity coefficients includes 1% for nonideality.  相似文献   

8.
《Fluid Phase Equilibria》2002,200(1):41-51
Vapor–liquid equilibrium (VLE) data are reported for the binary mixtures formed by octane and the branched ether 1,1-dimethylpropyl methyl ether (tert-amyl methyl ether or TAME). A Gibbs–van Ness type apparatus was used to obtain total vapor pressure measurements as a function of composition at 298.15, 308.15, 318.15 and 328.15 K. The system shows positive deviations from Raoult’s law. These VLE data are analyzed together with data previously reported for octane+TAME mixtures: VLE data at 323.15 and 423.15 K, excess enthalpy (HmE) data at 298.15 and 313.15 K and excess volume (VmE) data at 298.15 K. The UNIQUAC model, the lattice–fluid (LF) model, and the Flory theory are used to simultaneously correlate VLE and HmE data. The two latter models are then used to predict VmE data. The original UNIFAC group contribution model and the modified UNIFAC (Dortmund model) are used to predict VLE data.  相似文献   

9.
Relative permittivity measurements were made on binary mixtures of (2-butanol + 2-butanone) and (2-butanol or 2-butanone + cyclohexane) for various concentrations at T = (298.2, 308.2, and 318.2) K. Some experimental results are compared with those obtained from theoretical calculations and interpreted in terms of homo- and heterogeneous interactions and structural effects. The molecular dipole moments were determined using Guggenheim–Debye method within the temperature range of (298.2 to 318.2) K. The variations of effective dipole moment and correlation factor, g, with the mole fraction in these materials were investigated using Kirkwood–Frohlich equation. The pure compounds showed a negative and small temperature coefficient of effective dipole moment. In order to obtain valuable information about heterogeneous interaction (interactions between the unlike molecules), the Kirkwood correlation factor, the Bruggeman dielectric factor and the excess permittivity were calculated. In order to predict the permittivity data of polar–apolar binary mixtures, five mixing rules were applied.  相似文献   

10.
The speeds of sound in 1-hexanol and 2-ethyl-1-butanol have been measured over the temperature range from (293.15 to 318.15) K and at pressures up to 101 MPa. The densities have been measured within the temperature range from (283.15 to 343.15 or 353.15) K under atmospheric pressure. For the measurements, a pulse-echo-overlap method and a vibrating tube densimeter have been used. Additionally, in the case of 2-ethyl-1-butanol, the isobaric heat capacities from T = (293.15 to 323.15) K at atmospheric pressure have been measured by means of a DSC calorimeter. The experimental results are then used to calculate the densities and isobaric heat capacities as a function of temperature and pressure by means of a numerical integration technique. The effects of pressure and temperature on these and the related properties are discussed. Densities are correlated by means of the Tait equation.  相似文献   

11.
The vapor pressures of (1,3-pentanediamine + water), or (1,5-diamino-2-methylpentane + water) binary mixtures, and of pure 1,3-pentanediamine or 1,5-diamino-2-methylpentane components were measured by means of a static device at temperatures between (273 and 363) K. The data were correlated with the Antoine equation. From these data excess Gibbs functions (GE) were calculated for several constant temperatures and fitted to a three order Redlich–Kister equation using the Barker’s method. The (1,3-pentanediamine + water) or (1,5-diamino-2-methylpentane + water) binary systems exhibit negative deviations in GE for all investigated temperatures over the whole composition. Additionally, the NRTL UNIQUAC and Modified UNIFAC (Do) models have been used for the correlation or prediction of the total pressure.  相似文献   

12.
A glass dynamic recirculating still was employed for the measurement of isothermal (vapour + liquid) equilibrium (VLE) data for the binary mixtures of diisopropyl ether (DIPE) + alcohol, viz. (DIPE + methanol), (DIPE + ethanol), and (DIPE + 1-butanol) at T = (305.15, 315.15, and 325.15) K, T = (313.15, 323.15, and 333.15) K and T = (318.15, and 338.15) K, respectively. The combined standard uncertainties in the reported system pressures, temperatures and phase compositions are ±0.2 kPa, ±0.1 K and ±0.003, respectively. Maximum pressure azeotropes were observed for all isotherms of the (DIPE + methanol) and (DIPE + ethanol) systems. The experimental results were correlated using both the γϕ and ϕϕ approaches. For the correlation of the VLE data with the γϕ approach, the Wilson, NRTL and UNIQUAC GE models with the truncated two-term virial equation of state (Hayden and O’Connell correlation for second virial coefficient computation) were used. In the ϕϕ correlation approach, the Peng–Robinson equation of state was used with the Wong–Sander mixing rules incorporating the same GE models used in the γϕ approach. Comparisons between the experimental values and predictions using UNIFAC (Dortmund) and the Predictive Soave–Redlich–Kwong (PSRK) model were performed to test the predictive capabilities of these models for the experimental data measured here. The thermodynamic consistency of the experimental data was checked with the Herington area test.  相似文献   

13.
The vapor pressure of pure 2-methyl-1-propanol and 3-methyl-1-butanol, components called congeners that are present in aroma of wine, pisco, and other alcoholic beverages, were measured with a dynamic recirculation apparatus at a pressure range of (15 to 177) kPa with an estimated uncertainty <0.2%. The measurements were performed at temperature ranges of (337 to 392) K for 2-methyl-1-propanol and (358 to 422) K for 3-methyl-1-butanol. Data were correlated using a Wagner-type equation with standard deviations of 0.09 kPa for the vapor pressure of 2-methyl-1-propanol and 0.21 kPa for 3-methyl-1-butanol. The experimental data and correlation were compared with data selected from the literature.  相似文献   

14.
Isobaric (vapour  +  liquid) equilibrium (v.l.e.) of (1,3-dioxolane, or 1,4-dioxane  +  1-butanol, or 2-butanol) at 40.0 kPa and 101.3 kPa have been studied with a dynamic recirculating still. The experimental data for all mixtures were checked for thermodynamic consistency using the method of Van Ness. Activity coefficients calculated from (v.l.e.) data have been correlated with different equations (Wilson, Van Laar, Margulles, NRTL, and UNIQUAC), giving satisfactory results. Predictions with the group contribution methods ASOG and UNIFAC were also obtained.  相似文献   

15.
《Fluid Phase Equilibria》2006,239(2):200-205
Isothermal vapor–liquid equilibrium (VLE) data were measured for the binary systems of nitrogen with 2-propanol, 2-butanol, or 2-pentanol at temperatures from 333.15 to 393.15 K and pressure up to 100 bar. Henry's constants of nitrogen in these three sec-alcohols were determined by using the Krichevesky–Ilinskaya equation. The experimental VLE data were also correlated by the Peng–Robinson and the Patel–Teja equations of state with various mixing rules.  相似文献   

16.
Physico-chemical properties viz., density, viscosity, and refractive index at temperatures = (298.15, 303.15, and 308.15) K and the speed of sound at T = 298.15 K are measured for the binary mixtures of methylcyclohexane with ethanol, propan1-ol, propan-2-ol, butan-1-ol, 2-methyl-1-propanol, and 3-methyl-1-butanol over the entire range of mixture composition. From these data, excess molar volume, deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility have been calculated. These results are fitted to the polynomial equation to derive the coefficients and standard errors. The experimental and calculated quantities are used to study the nature of mixing behaviours between the mixture components.  相似文献   

17.
In this work, we present the experimental measurements of excess molar enthalpies for the binary systems of dibutyl ether with different isomers of pentanol: 1-pentanol, 2-pentanol, 3-pentanol, 3-methyl-2-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-methyl-2-butanol; all of them at T = (298.15 and 308.15) K and atmospheric pressure. Our goal was to determine the influence of the OH-group position on the different isomers of pentanol in the excess molar enthalpies of the binary systems studied. For this purpose we have analysed their experimental effective-reduced dipole moments. All values of excess molar enthalpies for the mixtures studied are positive whereas the results obtained for the effective-reduced dipole moments of the isomers of pentanol are similar.  相似文献   

18.
Vapour pressures of (1-chlorobutane  +  1-butanol, or 2-methyl-2-propanol) at several temperatures between T =  278.15 and T =  323.15 K were measured by a static method. Reduction of the vapour pressures to obtain activity coefficients and excess molar Gibbs energies was carried out by fitting the vapour pressure data to the Redlich–Kister equation according to Barker’s method. For (1-chlorobutane  +  2-methyl-2-propanol) azeotropic mixtures with a minimum boiling temperature were observed over the whole temperature range.  相似文献   

19.
Density data for dilute aqueous solutions of 1-butanol, 2-butanol, 2-methyl-1-propanol (iso-butanol), and 2-methyl-2-propanol (tert-butanol) are presented together with partial molar volumes at infinite dilution calculated from the experimental data. The measurements were performed at temperatures from T = 298.15 K up to T = 573.15 K and at pressure close to the saturated vapour pressure of water, at pressures close to p = 20 MPa and p = 30 MPa. The data were obtained using a high-temperature high-pressure flow vibrating-tube densimeter.  相似文献   

20.
Experimental values of density, refractive index and speed of sound of (hexane  +  cyclohexane  +  1-butanol) were measured at T =  298.15 K and atmospheric pressure. From the experimental data, the corresponding derived properties (excess molar volumes, changes of refractive index on mixing and changes of isentropic compressibility) were computed. Such derived values were correlated using several polynomial equations. Several empirical methods were used in the calculation of the properties of ternary systems from binary data. The Nitta–Chao group contribution model was applied to predict excess molar volume for this mixture.  相似文献   

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