(667f) Interpretation of the Bourne Segregation Parameters for Serial Competitive Reactions

In order to clarify the information available in the segregation parameters described by John Bourne and coworkers and to develop improved strategies for the minimization of byproducts in reactive mixing, the combined kinetic and diffusion equations have been solved numerically. For serial competitive reactions [A + B ?» C (k1) and C + A ?» D (k2)], the calculations have been carried out for an idealized system in which the two primary reactants are initially present in periodic lamina. The reaction rates, the thicknesses of the lamina, the concentrations and/or the number of moles of each reactant may be varied. The results are presented in terms of four dimensionless parameters: a Damkohler number (k1CA0/DLA2) where CA0 is the initial concentration of reactant A and D is the diffusion coefficient, the ratio of the rate of the byproduct reaction to the primary reaction (k2/k1), the ratio of the number of moles (nA/nB), and the ratio of the thicknesses of the two lamina (LA/LB). Examples will be presented of parameter sets in which the initial conditions lead to (1) low amounts of byproducts and (2) to high amounts of byproducts.