Reactions with More Than One Phase

All of the previous examples have been for reactions completely in one phase. However, there is no restriction in the basic equations in Chapter 12 that says that they must all be in the same phase, as the following examples show. 

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Mass transfer is also important in successfully scaling up a process. Mass transfer (which is not the same as agitation) becomes very important in a reaction with more than one phase and in work-up and purification. For substances to react they must come into contact. In a two-phase system, mass transfer is affected by the rate of diffusion to and across the interfacial boundary and the rate of diffusion of products from the reaction zone. Mass transfer is affected by the size of the interfacial area or surface as well. 

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