Isotachic pattern

Then, band profiles eventually develop into the isotachic pattern of pure component bands moving at the velocity of the displacer front. In Example 12, this occurs at = 0.765. 

Analysis of the Isotachic Pattern When There is Selectivity Reversal at High Concentrations. 446... 

Antia and Horvath [32] have provided an analysis of the isotachic patterns in displacement chromatography that take into accormt the effects of a selectivity reversal. They used for this purpose the multicomponent isotherm generated by the IAS theory. In order to examine the possibility of performing separations even when the single-component isotherms of two components intersect and cross over, they analyzed the stability of the displacement train and the criteria for displacement and for the stability of the resulting botmdaries that are established in an isotachic train. 

In this case, as shown above, a constant pattern is reached, and a shock layer propagates at the velocity predicted by the ideal model [1,3]. The velocity of the isotachic train is the velocity of the front shock of the displacer breakthrough curve... 

Isotachic train Asymptotic solution of the displacement problem. Each component zone pushes in front of it the zones of the less strongly adsorbed components and is pushed by those of the more strongly adsorbed ones (see Chapters 9 and 12). A constant pattern is reached and all the zones move at a constant velocity. 

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