A new organic reductant, caffeic acid, gives rise to sustained oscillation in the bromate-manganous-sulfuric acid system. Oscillation pheneomena can be observed in both batch reactors and continuous-flow stirred tank reactors. The activation energies of the oscillating reaction and its induction period have been calculated from the experimental data with good linear dependent coefficients According to the general stability condition, a typical two-dimensional cros-shaped diagram has been shown by a series of experiments with various flow rates and concns. of reactants.

Key words: SULFURIC ACID, POTASSIUM COMPOUNDS, CHEMICAL OSCILLATIONS, MANGANESE ION, BROMATE, CAFFEIC ACID, PHASE DIAGRAM