KINETIC-MODEL OF THE HYDROGEN OXYGEN REACTION ON PLATINUM - BISTABILITY, CHEMICAL WAVES AND OSCILLATIONS

The kinetic model, developed earlier to describe catalytic ignition in the hydrogen-oxygen reaction on a Pt wire at P(H-2) + P(O2) almost-equal-to 100 Torr and T = 300-500 K, predicts a hysteresis in the reaction rate at low hydrogen partial pressures. Employing this model and taking into account hydrogen surface diffusion, we analyze the stability of the steady-state regimes in the bistable region at T = 200-500 K and P(H-2) + P(O2) = 10(-6)-10(2) Torr, and estimate the velocity of propagation of the chemical waves which are possible in this case. Including oxide formation on the Pt surface into the reaction scheme, we also explore oscillations in the hydrogen oxidation at P(H-2) + P(O2) almost-equal-to 100 Torr and T = 400-500 K.