Disperse Phase to Wall Mass Transfer

N ow we consider the case of mass transfer from the bubble to a catalyst that is deposited at the wall of the micro reactor channel, at which a dissolved gas is converted rapidly. 

The rate of transfer to the wall may be estimated from film theory as fe = D/6f for a given film thicknes s 5 F. We as sume here that 5 is the same within the slug, i. e. the liquid layer close to the wall is not partaking in the recirculation and the bubble, and obtain 

For the bubble region, the mass transfer rate can be estimated from film theory  

In the slug region, the same approach can be used, with the concentration in the circulating zone the following mass transfer rats is obtained  

The problem of formulating a mass transfer model can now be reduced to the problem of formulating a model that predicts the average slug concentration. Using penetration theory for the caps, it can be shown that 

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