Reaction time distribution mixing theory

Most chemical reaction engineering textbooks contain material on residence time distribution theory. Levenspiel [17] and Hill [18] present particularly useful introductions as do refs. 9 and 16. The proceedings of a recent summer school [19] contains a brief overview of the field [8] as well as papers describing many specific applications of RTD theory in chemical engineering contexts. Nauman s comprehensive invited review cited earlier [4] is an extremely thorough and yet highly readable contribution to the literature. The book by Nauman and Buffham [20], will no doubt fill a most important gap in the literature on mixing in continuous flow systems. 

These results constitute the first major steps in formalizing statistical theories of reaction dynamics and relating statistical molecular behavior to ergodic theory. Specifically, they demonstrate that by invoking a mixing condition on a well-chosen R we obtain an analytically soluble model for P(t) which is asymptotically well approximated by exponential decay with rate K. The rate of decay is directly affected by the relaxation time t and equals ks(R) in the limit t - 0. A similar approach can be used46 to provide an ergodic theory basis for product distributions. 

It could be that different mechanisms take place on the catalyst surface at the same time (i.e., that different monomers are involved in the chain growth process). Even if two or more different mechanisms operate at the same time, the overall distribution would probably still be as per the ASF theory. The mix of alkenes, alkanes, o genated products, and other products could then depend on the relative contributions of the various mechanisms. In chapter 3 of Reference 7, the possibility of how the various surface species (CO, HCOH, CH2, H, OH, and H2O) may be involved in the reactions occurring on the catalyst surface is proposed. 

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