TAP-2 - AN INTERROGATIVE KINETICS APPROACH

The TAP-2 reactor system and the theoretical basis of TAP pulse respon se experiments are discussed. On the basis of the TAP system, an alter native to the traditional kinetic approach in heterogeneous catalysis is developed. This new approach, termed 'interrogative kinetics' invol ves a combination of two types of kinetic experiments called 'state-de fining' (friendly) and 'state-altering' (typical) experiments. The sta te defining kinetic parameter, or 'kinetic parameter of the catalyst' (KPC) is proposed and compared with the kinetic characteristic 'turnov er number'. The theory of TAP pulse response experiments is developed. Two deterministic models based on partial-differential equations are analyzed for the cases of diffusion, irreversible adsorption/reaction and reversible adsorption. The 'standard diffusion curve' that can be used for distinguishing the Knudsen flow regime is described, and simp le criteria of the Knudsen regime are proposed. The concept of relativ e flow is described, and different fingerprints of TAP kinetics for ir reversible adsorption/reaction and reversible adsorption are presented . TAP-2 experimental results on the selective oxidation of n-butane ar e used to illustrate the methodology of interrogative kinetics.