Excess thermodynamic functions for ternary systems. I. Acetone-chloroform-methanol at 50.deg.

Abstract

Extensive heat-of-mixing data taken wlth an isothermal tltration calorimeter for the acetone-chloroform-methanol system at 5OoC are reported, and a correlation of the results Is presented. When combined wlth a correlatlon for the excess Gibbs free energy reported earlier, these results allow calculation of excess entropies.The isothermal titration calorimeter described by Winterhalter and Van Ness (9) has been used without modification for measurement of heats of mixing for the system acetonechloroform-methanol over the full composition range of the ternary system. Included are data for the constituent binaries; for ternary mixtures 15 runs were made by addition of a pure component to an initial mixture made up of known amounts of the other two components. The extent of coverage of the ternary composition diagram is indicated by the lines of Figure 1.The chemicals employed were chromatoquality reagents supplied by Matheson Coleman & Bell; they were used as received with a minimum indicated purity of 99.8 mol %. Data for Binary SystemsThe experimental results for the three binary systems, acetone( 1)-chloroform(2), acetone( l)-methanol(3), and chloroform(2)-methanol(3), are given in Table I (deposited with the ACS Microfilm Depository Service). These data are well correlated by equations of the form: ---Ajpj + AI?~ -HE XixglT (Xjixi + XfljIXix, +

Excess enthalpies of (di-n-butyl ether + 2,2,4-trimethylpentane + heptane, or octane) at the temperature 298.15 K

“…which was adopted for the latter contribution, is similar to the form used by Morris et al (10) with an extra skewing factor (1 − x 1 + x 2 ) −1 inserted. Values of the coefficients c i were obtained from least-squares analyses in which equations (3) and (4) were fitted 1 0with this rise is more extensive for the nC7 mixture.…”

Excess enthalpies of some (1-propanol + methyl tert-butyl ether + C6-hydrocarbon) ternary systems at 298.15 K

“…As in our previous work (I, 2,7, 9, lo), the values of H i were represented as a sum of binary terms (12) with an added ternary contribution and following Moms et al (13), the form was adopted for the ternary term. For each system, the values of the parameters ck were determined by the method of least squares, and the results of the analyses are given in the footnotes of Tables 1-3 …”

Excess enthalpies of { ethyl tert -butylether + hexane + heptane, or octane } at the temperature 298.15 K

“…, x 1 + x 2 = 1, reference 1; ·-·, x 2 = 0, reference 1; --, calculated from the representation of the results by equations (2) to (4), using the ternary term H E m,T given in the footnote of table 3; ----, estimated from the Liebermann and Fried model. which was adopted for the latter contribution is similar to the form used by Morris et al, (8) but with an extra skewing factor (1 − x 1 + x 2 ) −1 inserted. Values of the coefficients c i were obtained from least-squares analyses in which equations (3) and (4) Equations (2) to (4) were also used to calculate the constant H E m,123 contours plotted on the Roozeboom diagrams in figures 3(a) and 4(a).…”