Binary Mixtures of Nonelectrolytes

Dilute Dispersions of Macromolecules in Nonelectrolytes The Stokes-Einstein equation has already been presented. It was noted that its validity was restricted to large solutes, such as spherical macromolecules and particles in a continuum solvent. The equation has also been found to predict accurately the diffusion coefficient of spherical latex particles and globular proteins. Corrections to Stokes-Einstein for molecules approximating spheroids is given by Tanford Physical Chemistry of Macromolecules, Wiley, New York, (1961). Since solute-solute interactions are ignored in this theory, it applies in the dilute range only. 

Concentrated, Binary Mixtures of Nonelectrolytes Several correlations that predict the composition dependence of DAB are summarized in Table 5-15. Most are based on known values of DAB and Dba- In fact, a rule of thumb states that, for many binary systems, DAB and Dba bound the Dab vs. xa curve. Cullman s [8] equation predicts diffusivities even in lieu of values at infinite dilution, but requires accurate density, viscosity, and activity coefficient data. 

TABLE 5-15 Correlations of Diffusivities for Concentrated, Binary Mixtures of Nonelectrolyte Liquids 

Caldwell-Babb [5] Rathbun-Babb [20] Vignes[28] Leffler-Cullinan [16] 

Asfour-Dullien [1] Siddiqi-Lucas [22] Bosse and Bart no. 1 [3] 

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Dilute Binary Mixtures of Nonelectrolytes with Water as the... 

TABLE 5-18 Correlations for Diffusivities of Dilute/ Binary Mixtures of Nonelectrolytes in Liquids... 

Concentrated, Binary Mixtures of Nonelectrolytes Several correlations that predict the composition dependence of Dab snm-... 

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