Reactive distillation line diagram

RD is a feasible alternative for systems where the desired products are the nodes in a reactive distillation line diagram and their boiling points differ considerably,... 

Bessling, B., Schembecker, G., and Simmrock, K. H. (1997). Design of Processes with Reactive Distillation Line Diagrams. Ind. Eng. Chem. Res. 36, 3032-3042. 

These analogies become particularly clear if we look at the synthesis of methyl acetate (MeAc) from methanol (MeOH) and acetic acid (HAC) as an example. Essentially, we see diagrams that are similar to the distillation line diagrams of non-reactive systems. As a result of the transformation, the four pure substances lie at the comers of a square and the non-reactive binary systems lie along the edges. 

Jimenez L., Wanhschafft O. and Julka V. (2000). Synthesis of reactive and extractive distillation units using distillation line diagrams. Computer-Aided Chemical Engineering 8, 985-990. 3.2.2... 

The munber of theoretical and reactive stages is determined from the distillation line and from the intersection of the distillation line and chemical equilibrium manifold (GEM) and represents the boimdary of the forward and backward reactions) (Giessler et al., 1999). Since there are multiple pairs of X and product composition that satisfy the mass balance, the method sets one of the product composition as reference point and solves for the other two (for a 3-component system) by using material balance expressions. Thus, two of the components compositions and X lie on the same line of mass balance (LMB) in the diagram and allow the estimation of the ratio D/B at a certain reboil ratio only by exploring the ratio of the line segments (figure 3.1f>). 

Fig. 5.9 shows the geometric representation of these balances in the McCabe-Thiele diagram. The distillate composition xP is located at the intersection of the condenser operating line and the operating line of the RD section. By specifying xP, the number of reactive trays can be estimated from the classical staircase construction. From the intersection of the operating line of the column section with that of the reboiler line, the bottom composition is determined. 

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