Relationship between effective and ideal separation factors for distillation and sublimation

摘要

General aspects of the relationship between the effective (beta) and ideal (beta(i)) separation factors for the distillation and sublimation of elemental substances containing low-volatile impurities have been established. It has been shown that the difference between beta and beta(i) may be both insignificant and extremely large: 4 to 16 orders of magnitude or even more. In host-impurity systems having the same host, the difference between beta and beta(i) decreases as beta(i) approaches unity, all other factors being the same. The difference between beta and beta(i) is moderate, within one order of magnitude, when beta i differs from unity by no more than three orders of magnitude. In a given host-impurity system, the difference between beta and beta(i) increases with decreasing impurity concentration. In individual systems, the difference between beta and beta(i) increases with increasing yield at a given initial impurity concentration.