Mechanism for the uncatalysed Belousov–Zhabotinskii reaction in open systems

Abstract

An eight-reaction-step model for the kinetic behaviour of uncatalysed Belousov–Zhabotinskii (BZ) systems in a well stirred, continuous flow reactor is presented on the basis of bromide-ion control. The predicted behaviour is compared with experimental results for the system with gallic acid as the organic substrate. Important features of the model include the production of an organic intermediate with quinone structure, obtained via the reaction of the primary reagents bromate and gallic acid. The quinone can participate in a one-electron transfer process thus playing a similar role in completing the autocatalytic cycle to that of the metal ion in conventional catalysed BZ systems.