Simple and Complex pH Oscillations and Bistability in the Phenol-Perturbed Bromite-Hydroxylamine Reaction

Article abstract of DOI:10.1021/j100062a032

The unbuffered reaction between bromite and hydroxylamine at pH 3-7 has been studied under closed and open conditions.The stoichiometry of the batch system depends on the initial concentration ratio of the reactants and on the starting pH.The reaction is strongly autocatalytic in H⁺.Under flow conditions the reaction exhibits bistability between two steady states but does not oscillate.If the flow system is perturbated by an input of phenol, it shows oscillatory behavior in pH, potential of a Pt electrode, and color.A qualitative explanation of the batch and oscillatory behaviors is suggested.The bromite-hydroxylamine-phenol flow system can be characterized as a large-amplitude, long-period, pH-driven oscillator.