ABSTRACT
With the exception of the discussion of reactions on surfaces in Chapter 3 and some references to fixed-bed reactors in Chapters 5 and 6 , we have largely been concerned with reactions in homogeneous phases (or pretended so) and corresponding reactor models. Although those models are not completely restricted to reactions in homo geneous phases, there are a number of properties of reactions in heterogeneous systems, particularly when we get down to more detailed analysis, which are suffi ciently important that they must be treated separately.