log-

= kx2ct

Regarding the definition of relative volatility and combining Eqs. (41) - (43), it is derived:

When component A and B are at infinite dilution, it becomes: aT

where a" and a™ represent relative volatilities at infinite dilution with salt and no salt.

Eq. (45) presents the relationship of salting coefficients and relative volatilities at infinite dilution, and constructs a bridge between microscale and macroscale. Even if the calculated salting coefficients aren't accurate due to the current limitation of scaled particle theory, it isn't difficult to judge the magnitude of ks i and ka by the conventional thermodynamics knowledge and decide whether it is advantageous to improve the relative volatilities with salt. From Eq. (45) it is concluded that if ks \ > ka with low salt concentration, the relative volatilities of components to be separated will be increased by adding salt; the more great the difference between ks\ and ka- the more apparent the effect of improving relative volatility.

The value of a„ can be derived from experiment or calculation using a vapor pressure equation and liquid activity coefficient equation. According to Eq. (45), it is convenient to obtain the values of a" just by calculating salting coefficients according to scaled particle theory.

Differentiating Eqs. (42) and (43) with respect to c, we can write in an ordinary expression:

In terms of scaled particle theory, we obtain

In terms of scaled particle theory, we obtain

<9 log c^ |
= ky = |
~d(g['/2.3kT) |
+ |
d(g[ / 2.3AT) |

{ J |

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