Azeotropic data

Compilation of azeotropic data as well as other physical properties including melting and boiling points. 

VL = vapor-liquid equilibrium data MS = mutual solubility data AZ = azeotropic data... 

There is a considerable amount of experimentaldata for properties of mixtures wherein toluene is a principal constituent. Compilations and bibhographies exist for vapor—hquid equihbrium measurements (9,10), hquid—hquid equihbrium measurements (11), and azeotropic data (12,13). 

The physical and thermodynamic properties of benzene are shown in Table 1 (2). Azeotrope data for benzene with selected compounds are shown in Table 2 (3). Benzene forms minimum-boiling azeotropes with many alcohols and hydrocarbons. Benzene also forms ternary azeotropes. 

Even though the simple distillation process has no practical use as a method for separating mixtures, simple distillation residue curve maps have extremely usehil appHcations. These maps can be used to test the consistency of experimental azeotropic data (16,17,19) to predict the order and content of the cuts in batch distillation (20—22) and, in continuous distillation, to determine whether a given mixture is separable by distillation, identify feasible entrainers/solvents, predict the attainable product compositions, quaHtatively predict the composition profile shape, and synthesize the corresponding distillation sequences (16,23—30). By identifying the limited separations achievable by distillation, residue curve maps are also usehil in synthesizing separation sequences combining distillation with other methods. 

Schematic DRD shown in Fig. 13-59 are particularly useful in determining the imphcations of possibly unknown ternary saddle azeotropes by postulating position 7 at interior positions in the temperature profile. It should also be noted that some combinations of binary azeotropes require the existence of a ternaiy saddle azeotrope. As an example, consider the system acetone (56.4°C), chloroform (61.2°C), and methanol (64.7°C). Methanol forms minimum-boiling azeotropes with both acetone (54.6°C) and chloroform (53.5°C), and acetone-chloroform forms a maximum-boiling azeotrope (64.5°C). Experimentally there are no data for maximum or minimum-boiling ternaiy azeotropes. The temperature profile for this system is 461325, which from Table 13-16 is consistent with DRD 040 and DRD 042. However, Table 13-16 also indicates that the pure component and binary azeotrope data are consistent with three temperature profiles involving a ternaiy saddle azeotrope, namely 4671325, 4617325, and 4613725. All three of these temperature profiles correspond to DRD 107. Experimental residue cui ve trajectories for the acetone-...

List multiple temperature profiles when you have incomplete azeotropic data. 

Horsley, L. H., Azeotropic Data, Advances in Chemistry Series, American Chemici Society, Washington, D.C. 

L.D. Horsley, Tables of Azeotropes and Non azeotropes in Azeotropic Data , Advances in Chemistry Series No 6, ACS... 

Estimation of activity coefficients from azeotropic data... 

Horsley, L. H. Azeotropic Data II Advances in Chemistry 35 American Chemical Society Washington, DC, 1962 p 61. 

The recovery process must also be kept in mind, and fundamental vapor liquid data, such as the formation of azeotropes, should be examined. Azeotropic data can be found in the literature [1], but are sometimes contradictory. Finally, solvents that are unstable, toxic, expensive, and high grade should be avoided, unless the product price is high and the feed flow rate is low. 

Lecat (32) is responsible for most of the azeotropic data on binary and ternary systems. Recently, however, Horsley (25) has compiled extensive tables of azeotropic data, thus making the information more available. These experimental data may be supplemented by estimations of the azeotropic composition and behavior of unknown systems by several reasonably reliable methods. Graphical methods, based on curves developed from experimental data, have been proposed by Lecat (82), Mair et al. (.ffi), Horsley (26), Skol-... 

The theoretical and mathematical treatment of azeotropic data has been covered by several authors, including Benedict and coworkers (1), and Scheibel and Friedland (50). Licht and Denzler (37) have discussed the thermodynamic conditions necessary and sufficient for azeotropism. Colburn (8) has reviewed the calculations associated with azeotropic and extractive distillation, and Hodgson (24) stresses the relationship between azeotropic distillation, extractive distillation, and liquid-liquid extraction. 

There are two publications that list properties of azeotropic mixtures. Timmermans, The Physico-Chemical Constants of Binary Systems in Concentrated Solutions, 4 vols.. Interscience, New York, 1959-1960, is by far the more comprehensive. The other is Azeotropic Data, 2 vols., Advances in Chemistry Series no. 6 and no. 35, American Chemical Society, Washington, 1952, 1962. 

In some cases two or more liquids form constant-boiling mixtures, or azeotropes. Azeotropic mixtures are most likely to be found with components which readily form hydrogen bonds or are otherwise highly associated, especially when the components are dissimilar, for example an alcohol and an aromatic hydrocarbon, but have similar boiling points. (Many systems are summarised in Azeotropic Data - III, L.H.Horsley, Advances in Chemistry Series 116, American Chemical Society, Washington, 1973). 

Data of Azeotropes. The choice of azeotropic entrainer for a desired separation is much more restricted than that of solvents for extractive distillation, although many azeotropic data are known. The most extensive compilation is that of Ogorodnikov, Lesteva, and Kogan (Handbook of Azeotropic Mixtures (in Russian), 1971). It contains data of 21,069 systems, of which 1274 are ternary, 60 multicomponent, and the rest binary. Another compilation Handbook of Chemistry and Physics, 60th ed., CRC Press, Boca Raton, FL, 1979) has data of 685 binary and 119 ternary azeotropes. Shorter lists with grouping according to the major substances also are available in Lange s Handbook of Chemistry... 

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