New tendencies in the kinetics of heterogeneous catalytic reactions

Modern tendencies in the kinetics of heterogeneous catalytic reactions asso ciated with the consideration of the interaction of the catalyst with the r eaction medium (including the conjugation of the catalytic reaction with th e transformation of the catalyst) and of the participation of chemisorbed i ntermediates in heterogeneous catalysis were examined. It was shown that th ese effects are responsible for nonlinearity in the kinetic description of catalytic processes even for simple reactions occurring at equivalent activ e sites. These effects complicate the structure of the kinetic scheme and m ake more difficult solving the reverse kinetic problem of establishing the mechanism of a reaction from its kinetic characteristics. For the synthesis of methanol, as an example, it was demonstrated that the kinetic model of reactions involving firmly sorbed products is similar to the classical mode l of two-center reactions. It was argued that the contribution from the non uniformity of the surface is not as great as previously believed.