Behavior in Reported Kinetic Data

A search was made of the literature concerned with heterogeneous catalytic reactions to collect all kinetic data appropriate for the identification and quantitative comparison of compensation behavior. This survey necessarily sought every report in which the authors concerned described an observed 

This review is primarily concerned with those kinetic measurements for which reaction rates are referred to equal areas of solid, so that a consistent 

Comparisons made below refer to kinetic data obtained for processes proceeding under similar conditions. All available values of (log A, E) within each group of related reactions were included in the linear regression analysis (Appendix II) and the compensation line was calculated using these formulas. Unless otherwise stated, the units of A are always molecules m-2 sec-1 at 1 Torr pressure of reactants and those of E are kJ mole-1. The compilation of Arrhenius parameters referred to identical reaction conditions is not always easy (or, indeed, possible in some instances) and it may be necessary to recalculate data from literature sources using an extrapolation. Not all details of the necessary corrections are recorded below, but such estimations were always minimized to preserve the objectivity of the conclusions reached. 

The general form of the Arrhenius equation as used in studies of heterogeneous reactions normally includes pressure dependence terms of the form 

Despite these difficulties and limitations (which are not necessarily applicable or significant in all systems) very many instances of apparent obedience to Eq. (2) are found in the literature, which apply to data compiled from observations reported by different workers. This suggests that the level of catalytic activity, rather than the absolute values of A and E, is the dominant characteristic feature of catalytic behavior. 

---