The Product Is a Pure Component

The pure component is a separation product of three-component mixture at direct and indirect splits (1 2,3 or 1,2 3) if this component is the lightest or the heaviest one (i.e., if component point is node point of concentration triangle). 

Let s examine, first, the ideal mixture (ATi K2 K, xdi = 1 Fig. 5.11). We gradually increase the parameter L/V. At L/V Kj (K is phase equilibrium coefficient of component 3 in vertex 1) Eq. (5.9) is not valid for sides 1-2 and 1-3 adjacent with vertex 1. Therefore, vertex 1 is the stable node iV+ (Fig. 5.11a) (i.e., it can not be distillation product point). At such values of the parameter L/V the process, opposite to distillation process, the process of distillation flows mixing is feasible (see Chapter 2). 

AtL/V = Kl, there is first bifurcation, Eq. (5.9) becomes valid for side 1 -3 and not valid for side 1-2, vertex 1 turns into saddle S (Fig. 5.11b). 

At L/V = K2, there is second bifurcation, trajectory tear-off from vertex 1 along sides 1-2 and 1-3 becomes feasible (i.e., inside concentration triangle vertex turns into unstable node N ) (Fig. 5.11c), distillation process for the product point under consideration becomes feasible, trajectory bundle with the saddle point S at side 1-2 and, with the stable node at side 1-3 in the vicinity of vertex 1, appears S  

K are the phase equilibrium coefficients at vertex 1 for components 2 and 3, respectively. 

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