Separation of mass transfer from chemical reaction

Separation of mass transfer from chemical reaction 

In most two-phase processes at least one reactant has to be transferred from one phase to the other, to be able to react with the other reactant. In section 4.4 it has been indicated that mass transfer processes create concentration differences, which usually are limited to very thin zones close to the interfaces (diffusion layers). The conditions of the chemical reactions may be such that chemical conversion in that thin zone is negligible or even completely absent. This will be treated first. Chemical reaction and diffusion taking place in the same zone will be treated in section 5.4. 

These situations will be treated in the next three sections. 

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