Schematic representation of the Film Model

The definition of Damkohler number implies that no reaction takes place if Da 1 and chemical equilibrium limit is reached if Da 1. 

Homogeneous reactive distillation takes place in bubble-cap or sieve trays columns, where the residence time and liquid holdup needed for the chemical reaction are de- 

The solutions of each situation involve the simultaneous formulation of convenient chemical reaction and mass transfer models. For the case of phase equilibrium the widely spread equilibrium-based model (Seader, 1985) should be considered. In the case of rate limited mass transfer non-equilibrium models (Taylor and Krishna, 2000, 1993 Wesselingh, 1997) are to be used. The effect of Damkohler number on the unit performance should be taken into account if the chemical reaction is rate-limited. A detailed overview of the aforementioned situations is given in section 2.5. 

Heterogeneous reactive distillation operation -sometimes referred to as catalytic distillation- is carried out in a catalyst-containing packed column. The chemical reaction takes place (mostly) within the catalyst particle, whereas the packing allows for simultaneous reaction and mass transfer between vapor and liquid phases (Yuxiang and Xien, 1992, a Subawalla and Fair, 1999). As stated by Yuxiang and Xien (1992 ), five mass transfer/reaction processes may occur simultaneously in a reactive bed of catalytic 

In recent years considerable attention has been drawn to the use of multiphase mono- 

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Figure 2.5. Schematic representation of the Film Model. The mass and heat transfer fluxes are assumed to be positive in the direction Uquid —> vapor.

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