首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 468 毫秒
1.
Total vapour pressures have been measured by the isoteniscope method for triethylamine + n-hexane, triethylamine + n-octane, and tributylamine + n-hexane at 298.15 K. The excess Gibbs free energies GE for the liquid phase have been calculated from the measurements; GE is positive for the triethylamine systems and negative for the tributylamine system. The excess enthalpies HE for these three mixtures and for tributylamine + n-octane have been measured at the same temperature. Except for tributylamine + n-hexane, all these HE's are positive.  相似文献   

2.
Heats of mixingH E at 298.15 K and 1 atm are reported for the ternary liquid mixture of cyclohexane (1) + benzene (2) + 1-chlorobutane (3). A Redlich-Kister type of equation was used to represent and correlate the results.  相似文献   

3.
A semi-continuous dilatometer for measuring excess volume is described. Excess volumes of p-xylene +n-hexane + n-octane, +n-decane, +n-dodecane, +n-tetradecane, and +n-hexadecane have been measured at 298.15 K as a function of composition.  相似文献   

4.
Excess molar volumes, VE, isentropic compressibility deviations, ΔκS, and excess molar enthalpies, HE, for the binary mixtures 2-methyl-tetrahydrofuran with 1-chlorobutane, 2-chlorobutane, 2-methyl-1-chloropropane and 2-methyl-2-chloropropane have been determined at temperatures 298.15 and 313.15 K, excess molar enthalpies were only measured at 298.15 K. We have applied the Prigogine-Flory-Patterson (PFP) theory to these mixtures at 298.15 K.  相似文献   

5.
Excess enthalpies and excess volumes at 298.15 K and atmospheric pressure have been measured for mixtures of n-hexane + (an equimolar mixture of n-tridecane + n-nonadecane). The agreement of the results with the corresponding results for mixtures of n-hexane + n-hexadecane is interpreted as confirmation of the applicability of the principle of congruence to multicomponent mixtures.  相似文献   

6.
Refractive indices for the ternary mixtures formed by each one of the isomers of butanol (1-butanol, 2-butanol, 2-methyl-1-propanol and 2-methyl-2-propanol), with n-hexane and 1-chlorobutane, have been measured at 298.15 K. From these data the refractive index deviations were calculated and fitted by Cibulka’s equation, and the refractive index deviations were related to the corresponding excess volumes of the mixtures. Furthermore, several mixing rules were used to predict both refractive indices and excess volumes of the ternary mixtures from their densities or refractive indices. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   

7.
Experimental densities (ρ) and speeds of sound (u) were obtained for the ternary system (2-butanol + 1-chlorobutane + tetrahydrofuran) at three temperatures: 283.15, 298.15 and 313.15 K. Excess molar volumes (V E ) and isentropic compressibility deviations (Δκ S ) have been calculated from experimental data. A discussion of the thermodynamic behavior of the ternary system in terms of molecular interactions and structural and packing effects is presented.  相似文献   

8.
The speed of sound and excess molar isobaric heat capacity at 298.15 K, and the excess molar volume at 303.15 K are reported for (n-dodecane + n-hexane). The results, in combination with the excess molar volume at 298.15 K published previously, are used to obtain the interaction parameters a12 and b12 for the mixture treated as a pure fluid obeying a generalized van der Waals's equation of state. Similar analyses, using results from our previous investigations, are presented for (di-n-propylether + n-heptane) and (benzene + cyclohexane).  相似文献   

9.
《Fluid Phase Equilibria》1986,25(2):195-208
Awwad, A.M. and Salman, M.A., 1986. Excess molar volumes and viscosities of binary mixtures of cyclohexane and n-alkane at 298.15 K. Fluid Phase Equilibria, 25: 195-208.Excess molar volumes, viscosities, excess molar viscosities, and excess molar activation energies of viscous flow were determined for binary mixtures of cyclohexane + n-pentane, + n-hexane, + n-heptane, + n-octane, + n-nonane, + n-decane, + n-dodecane, + n-tetradecane and + n-hexadecane at 298.15 K. The effect of orientational order of n-alkane on solution molar volumes and viscosities is investigated as well as the adequacy of the Flory theory and free volume theories used to predict solution molar volumes and viscosities. For longer n-alkanes VE, ηE and ΔG*E are positive and associated with the orientational order.  相似文献   

10.
《Fluid Phase Equilibria》2002,193(1-2):109-121
Isothermal vapor–liquid equilibrium (VLE) data at 353.15 K and excess molar volumes (VE) at 298.15 K are reported for the binary systems of ethyl acetate (EA)+cyclohexane and EA+n-hexane and also for the ternary systems of EA+cyclohexane+2-methyl pyrazine (2MP) and EA+n-hexane+2MP. The experimental binary VLE data were correlated with common gE model equations. The correlated Wilson parameters of the constituent binary systems were used to calculate the phase behavior of the ternary mixtures. The calculated ternary VLE data using Wilson parameters were compared with experimental ternary data. The experimental excess molar volumes were correlated with the Redlich–Kister equation for the binary mixtures, and Cibulka’s equation for the ternary mixtures.  相似文献   

11.
Speeds of sound of the ternary mixtures cyclohexane+1,3-dioxolane+2-butanol and n-hexane+1,3-dioxolane+2-butanol have been measured at the temperatures of 298.15 and 313.15 K. Isentropic compressibilities and excess isentropic compressibilities have been calculated from experimental data. We have also compared the experimental isentropic compressibilities with calculated values from the free length theory and the collision factor theory. Experimental results show positive values of excess isentropic compressibilities in almost the whole composition range for the ternary mixture containing cyclohexane, meanwhile they are negative for the mixture containing n-hexane. Such different behaviour of these systems is related to the large free volume shown by n-hexane. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
A previous study on the physical properties of 1-alkanol + n-alkane has establised a correlation between dielectric permittivity at 1 GHz and excess molar volumes for all binary systems that were studied. In order to determine whether this behaviour is similar at lower frequencies, relative permittivity was measured at 100 kHz. The refractive index was measured to explore the effects at higher frequencies. Mixtures under study are in particular the systems (1-butanol + n-hexane, or n-octane, or n-decane) at the temperature of 298.15 K and atmospheric pressure, over the entire composition range. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

13.
14.
Phase diagrams and excess volumes at 298.15 K have been measured for the four binary mixtures carbon disulphide+cyclohexane, +n-hexane, +1,5-hexadiene, and +1,5-hexadiyne. The results are discussed qualitatively in the light of recent theoretical calculations of the structure and thermodynamic properties of mixtures containing anisotropic molecules.  相似文献   

15.
Molar excess enthalpies HE have been measured as a function of mole fraction at atmospheric pressure and 298.15 K for the binary liquid mixtures of ethanal, propanal, butanal and pentanal + benzene or + tetrachloromethane. The results show that the excess enthalpies decrease with increasing the n-alkanal chain length, with negative values for n-pentanal.  相似文献   

16.
Densities have been obtained as a function of composition for ternary-pseudobinary mixtures of [(benzene + tetrachloromethane or n-hexane) + (cyclohexane + tetrachloromethane or n-hexane)] at atmospheric pressure and the temperature 298.15 K, by means of a vibrating-tube densimeter. Excess molar volumes, VmE, partial molar volumes and excess partial molar volumes were calculated from the density data. The values of VmE have been correlated using the Redlich–Kister equation and the coefficients and standard errors were estimated. The experimental and calculated quantities are used to discuss the mixing behavior of the components. The results show that the third component, CCl4 or n-C6H14, have quite different influences on the volumetric properties of binary liquid mixtures of benzene with cyclohexane.  相似文献   

17.
Abstract

The refractive indices of the ternary mixture acetone + methanol + n-hexane have been measured at 288.15 and 298.15 K and atmosphere in the whole composition diagram. Parameters of polynomial equations which represent the composition dependence of physical and derived property are gathered. the use of a multicomponent extension of Heller equation in order to predict excess molar volumes from refractive indices on mixing are tested against literature data, a comparative accuracy with currently available models being obtained.  相似文献   

18.
A Picker flow microcalorimeter was used to determine molar excess heat capacities, CEp, at 298.15 K, as function of concentration, for the eleven liquid mixtures: benzene+n-tetradecane; toluene+n-heptane, and +n-tetradecane; ethylbenzene+n-heptane, +n-decane, +n-dodecane; and +n-tetradecane; n-propylbenzene +n-heptane, and +n-tetradecane; n-butylbenzene+n-heptane, and +n-tetradecane. In addition, molar excess volumes, VE, at 298.15 K, were obtained for each of these systems (except benzene+n-tetradecane) and for toluene+n-hexane. The excess volumes which are generally negative with a short alkane, increase and become positive with increasing chain length of the alkane. The excess heat capacities are negative in all cases. The absolute ¦CEp¦ increased with increasing chain length of the n-alkane. A formal interchange parameter, Cp12, is calculated and its dependence on n-alkane chain length is discussed in terms of molecular orientations.  相似文献   

19.
The performance of the Picker dynamic-flow microcalorimeter, which is able to scan and record (in 20 min) the enthalpy of mixing directly as a function of concentration, has been investigated at 298.15 K by measuring the three standard systems: cyclohexane + n-hexane, benzene + cyclohexane and carbon tetrachloride + benzene. Results agree to within better than 1%, in a large central range of concentration with the most reliable published data.  相似文献   

20.
Calorimetric measurements of molar excess enthalpies, HE, at 298.15 K, of mixtures containing aromatic aldehydes of general formula C6H5(CH2)mCHO (with m = 0, 1 and 2) + n-hexane, n-heptane or benzene are reported, together with the values of HE at equimolar composition compared with the corresponding values of HE for the aromatic ketones in the same solvents. The experimental results clearly indicate that the intermolecular interactions between the carbonyl groups (CHO) are influenced by the intramolecular interactions between the carbonyl and phenyl groups, particularly for the mixtures containing benzaldehyde.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号