Kinetic modeling of the methanol-assisted autocatalytic methanol synthesis on Cu/ZnO/Al2O3

Methanol is of rising interest as a potential hydrogen storage molecule and chemical building block producible from green hydrogen and captured carbon dioxide. Although the reaction kinetics have been studied for decades and numerous models are available, new recent insights reveal that a so far not quantitatively considered autocatalytic reaction pathway is of large relevance in heterogeneously catalyzed methanol synthesis over Cu/ZnO/Al 2 O 3 catalysts. Inspired by these recent reports, an extended kinetic model was derived and parameterized exploiting the same data base used to parameterize earlier derived models. Thus, we provide the first model for quantifying the kinetics of the heterogeneously catalyzed methanol synthesis from CO/CO 2 /H 2 which includes a methanol-assisted autocatalytic reaction pathway. Various reduced model variants were derived from the suggested model. A comparison with these reduced models and also with recalibrated further literature models reveals that the incorporation of the autocatalytic reaction pathway is beneficial. This finding encourages further assessment and validation considering a broader data base. • Heterogeneously catalyzed methanol synthesis on CZA catalysts. • Adding an autocatalytic reaction pathway to the conventional network. • Derivation of reaction rate approaches for all assumed reactions. • Parameter estimation of the kinetic model. • Model comparison with reduced models and literature models.