THE EQUILIBRIUM DIAGRAMS, HEATS OF MIXING, DIPOLE MOMENTS, DENSITIES, AND BOILING POINTS OF THE SYSTEM ACETONE–CHLOROFORM–BENZENE

1961 ◽  
Vol 39 (4) ◽  
pp. 735-744 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
H. Friesen

The equilibrium diagrams show that a compound, stable in the solid state, is formed in the system chloroform–acetone, but no compound is formed in the binary systems chloroform–benzene and acetone–benzene. The ternary equilibrium diagram, the heats of mixing, and the dipole moments, all show that this compound continues to exist in the presence of benzene, up to a high concentration of benzene. Since a series of ternary mixtures is shown to exist having zero heat of mixing, it was thought that this series of mixtures might behave in a pseudoideal manner, but the determinations of density (molar volume) and boiling point show that this is not so.

1979 ◽  
Vol 44 (3) ◽  
pp. 808-822 ◽  
Author(s):  
Vladimír Dohnal ◽  
Jaroslav Vinš ◽  
Robert Holub

The Wilson, the enthalpic Wilson and the Orye equations were used for the simultaneous correlation of extensive data sets on VLE and heats of mixing of eight binary systems hydrocarbon-n-alcohol, viz. benzene-methanol, -ethanol, -n-propanol, -n-butanol, cyclohexane-ethanol, -n-propanol, -n-butanol and n-heptane-ethanol. The expected quadratic temperature dependence of parameters of these equations makes a good simultaneous description possible of excess free enthalpy and heat of mixing as a function of temperature. The Wilson equation gives demonstrably the best description of the experimental data. All the equations were as well used to predict excess heat capacities for the systems listed and the confidence intervals were estimated for the predicted results. The comparison with experimental data for four of these systems shows that the predicted excess heat capacities are in general in good agreement with the experiment; however, the Wilson equation yielded again the best results.


1968 ◽  
Vol 23 (11) ◽  
pp. 1805-1815 ◽  
Author(s):  
F. Becker ◽  
H. D. Pflug ◽  
M. Kiefer

The relationship between heats of mixing and chemical interactions has been investigated and is now discussed for three liquid binary systems, i. e. diethyl ether-chloroform, nitromethane-sulfuric acid, and isopropanol-isopropylamine. On the basis of a suitable equilibrium model, involving the formation of only one species of intermolecular compounds, equations HM= ƒ (N0Δ) (HM=heat of mixing, N0Δ =mole fraction of component A) are derived. The equations are convenient for representing the experimental data of symmetrical mixing curves, and they also allow us to calculate the thermodynamic quantities of the pertaining equilibrium reactions. Plotting HM versus N0Δ/ (—HM) should give a straight line over the whole concentration range, thus warranting a reliable criterion for the applicability of the equilibrium model. The heats of mixing were measured at 25° and 20°, respectively, using a new type of continuous dilution calorimeter, which supplied a sufficient number of accurate experimental data.


1966 ◽  
Vol 44 (10) ◽  
pp. 1183-1189 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
R. M. Chatterjee

The volume changes on mixing of the three binary mixtures, acetone–chloroform, benzene–chloroform, acetone–benzene, and the ternary mixture, acetone–chloroform–benzene, and their molar refractivities and viscosities, were determined.Determinations of total and partial vapor pressures were made. The systems acetone–chloroform and benzene–chloroform show negative deviations from Raoult's law. The system acetone–benzene shows positive deviations.The excess Gibbs free energies of mixing have been calculated for all systems. By combining these data with previously measured heats of mixing (1), the excess entropy has also been calculated. The curves representing zero excess volume, zero heat of mixing, zero excess free energy of mixing, and zero excess viscosity as functions of composition in the ternary system do not coincide. It, therefore, must be concluded that they result from compensating effects and do not represent ideality.


2000 ◽  
Vol 286 (1) ◽  
pp. 48-57 ◽  
Author(s):  
E Ma ◽  
H.W Sheng ◽  
J.H He ◽  
P.J Schilling

1978 ◽  
Vol 43 (3) ◽  
pp. 829-836 ◽  
Author(s):  
Ján Biroš ◽  
Antonín Živný ◽  
Julius Pouchlý

Part I. — Pressures below 760 mm . In a previous communication (‘Proc.’, A, vol. 82, 1909, p. 396) the approximate boiling points of a number of metals were determined at atmospheric pressure. Apart from the question of finding the exact relation between the boiling point and pressure, it is an important criterion of any method for fixing the temperatures of ebullition to demonstrate that the experimental values obtained are dependent on the pressure. It is specially desirable when dealing with substances boiling at temperatures above 2000° to have some evidence that the points indicated are true boiling points. Previous work on the vaporisation of metals at different pressures has been confined to experiments in a very high vacuum except for metals like bismuth, cadmium, and zinc, which boil at relatively low temperatures under atmospheric pressure. The observations were limited to very low pressures on account of the difficulty of obtaining any material capable of withstanding a vacuum at temperatures over 1400° and the consequent necessity for keeping the boiling point below this limit by using very low pressures. Moreover in the case of the majority of the metals, e. g. , copper, tin, ebullition under reduced pressure has never been observed. The difficulties indicated above were avoided by using a similar type of apparatus to that previously described, and arranging the whole furnace inside a vacuum enclosure, thus permitting of the use of graphite crucibles to contain the metal.


Author(s):  
M. E. Peshekhontseva ◽  
M. A. Maevskiy ◽  
I. S. Gaganov ◽  
A. V. Frolkova

Objectives. The conditions for the effective application of the sharp distillation technique (without a component distributed between the distillate and bottom flows) for the separation of quaternary zeotropic mixtures containing components with similar volatilities were determined. The area of energy advantage for the flowsheet based on the preliminary fractionation of the mixture, compared with the flowsheet, the first distillation column of which works based on the indirect separation mode, was identified for an ethyl acetate–benzene–toluene–butyl acetate system. Energy savings of up to 20% were achieved. The direct and indirect distillation modes can become competitive when the point of the original composition is located near single K-surfaces or in a region with a different ratio of distribution coefficients. Sharp distillation is not suitable for the separation of a mixture containing a pair of components exhibiting relative unity volatility with medium boiling points.Methods. The mathematical modeling in the Aspen Plus V.10.0 software package was chosen as the research method. The simulation was based on the Wilson local composition equation. The relative errors in the description of the phase equilibrium did not exceed 3%.Results. The structure of the vapor–liquid equilibrium diagram and diagram of surfaces of the unit component distribution coefficients were studied for the ethyl acetate–benzene–toluenebutyl acetate and acetone–toluene–butyl acetate–o-xylene systems. Flowsheets based on the sharp, indirect (both systems), or direct (second system) distillation modes were proposed. The distillation process was simulated, and the parameters of the column work were determined (the quality of the substances meets the State Standard requirements of the Russian Federation for minimal energy consumption).Conclusions. Recommendations regarding the use of sharp distillation for the separation of quaternary mixtures containing components with similar volatilities were devised.


1997 ◽  
Vol 12 (12) ◽  
pp. 3254-3259 ◽  
Author(s):  
J. Font ◽  
J. Muntasell ◽  
E. Cesari ◽  
J. Pons

Ball milling has been used as a solid-state mechanical alloying technique in two binary systems of plastic crystals: neopentylglycol/pentaglycerin (NPG/PG), showing a partial solubility in the ordered phase, and 2-amino-2-methyl-1,3-propanediol/tris(hydroxymethyl) (AMP/TRIS) whose immiscibility in this ordered solid phase is almost total. For the AMP/TRIS system the stable state at room temperature was reached by milling. Contrarily, for NPG/PG, DSC measurements reveal that an annealing period is required after milling. These results have been compared with those of the pentaglycerin/pentaerythritol (PG/PE) binary system, previously studied, whose miscibility is total at room temperature.


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