A new idea of the influence of solid materials on kinetics of chemical reactions

Abstract

The mechanism of heterogeneous catalysis is still under discussion. There is no clear theory which explains the mechanism of influence of materials on the rate of chemical reactions. All existing theories assume that specific materials, catalysts, decrease activation energy Ea. We hypothesize that for standard and catalyzed heterogeneous reactions the same Ea (real activation energy) is needed to trigger reaction processes. We propose that the difference between Ea and apparent activation energy (Eapp) can be presented as catalytic reaction activation energy (Ec). This hypothesis is based on the so-called αi model considering tribochemistry, work function, thermionic emission, and the negative ion–radical action mechanism. The proposed model assumes that mechanical work done on a solid material is accumulated in this material and then emitted as electrons and/or photons to the space in which the reaction takes place. The developed model includes a specific angle γ at which the reaction can be initiated, when the stream of energy eγ equals some 3–5 eV. Energy emitted by the surface as pulses of 3–5 eV can reach the value of Ea and trigger a heterogeneous catalytic process. The catalyst emits pulses of a high density energy flux and at the angle γ the value of emitted energy is equal to the real activation energy Ea.