ELECTROCHEMICAL OBSERVATION OF INSTABILITIES OF THE BELOUSOV-ZHABOTINSKII REACTION IN CSTR

The instabilities of the Belousov-Zhabotinskii reaction were studied i n an isothermal CSTR by varying the space velocity as bifurcation para meter. The time-dependent concentration of bromide ion and redox poten tial were observed, respectively, by a Ag-AgBr electrode and a platinu m-wire electrode under reaction-controlling conditions. The single-pea k periodic and the chaotic oscillations occur alternately with increas ing space velocity. The multipeak oscillations were also observed at h igher space velocities. Two kinds of chaotic oscillations were observe d, chaotic oscillations with amplitudes varying irregularly in the per iodic-chaotic sequence region and chaotic mixing of large and small am plitude in the multipeak oscillations region. An analysis of the phase portraits for these chaotic oscillations indicates that they correspo nd to low dimensional and fractal structures.