Bistability in the Oxidation of Arsenite by Iodate in a Stirred Flow Reactor

Article abstract of DOI:10.1021/ja00410a023

The reaction between arsenite and iodate at 25 deg C and pH 2.25 in a stirred tank reactor exhibits bistability over a range of flow rates and input arsenite and iodate concentrations.Observed steady-state I^- and I2 concentrations and points of transition between bistable and unistable behavior are in excellent agreement with values calculated from a simple model consisting of three overal component processes: (A) IO3^- + 3H3AsO3 = I^- + 3H3AsO4; (B) IO3^- + 5I^- + 6H⁺ = 3I2 + 3H2O; (C) I2 + H3AsO3 + H2O = 2I^- + H3AsO4 + 2H⁺.Implications for the recently discovered arsenite-iodate-chlorite-oscillating reaction are discussed.