Mechanistic studies on the bromate–1,4-cyclohexanedione–ferroin oscillatory system

Abstract

A chemical mechanism including 22 reactions and 15 species is suggested for describing the dynamical behavior of the ferroin controlled BrO₃⁻–1,4-cyclohexanedione (CHD) batch oscillator. The model represents an extended version of the mechanism developed to explain the oscillations in the ferroin-free BrO₃⁻–CHD system. The kinetics and rate constants for some additional reactions such as ones between ferriin and CHD, BrCHD (2-bromo-1,4-cyclohexanedione) and H₂Q (1,4-hydroquinone) and between ferroin and bromate were determined and incorporated in the mechanism of the BrO₃⁻–CHD reaction. The model proposed here simulates satisfactorily the behavior of the BrO₃⁻–CHD–ferroin oscillator at increasing concentration of ferroin and at the condition of [ferroin] = 0 mol dm⁻³.