Oxygen Production in the Oscillatory Bray−Liebhafsky Reaction

Abstract

The volume of gaseous oxygen produced during the Bray-Liebhafsky (BL) oscillating reaction was measured. The rates of oscillatory O 2 evolution were calculated and the geometrical effects of the Pt electrode surface, stirring rate, and addition of the surfactant on the oscillatory behavior were studied. A significant stirring rate and detergent effect is observed. The oxygen evolution results obtained are in satisfactory agreement with oscillatory behavior of the BL reaction monitored by potentiometric measurements. The idea that physical and chemical processes might couple in the gas evolving oscillators and similar systems was first suggested over fifteen years ago by Bowers and Noyes. The possibility that chemical processes may couple with both oxygen and iodine nucleation and evolution in order to cause, enhance, or suppress oscillations in the BL system is indicated.

Oxygen Production and Numerical Simulations of the Interphase Transport in the Modified Oscillating Briggs−Rauscher Reaction

“…The second hole was for a glass tube (diameter 0.5 cm), which was connected via tubing to a 250-mL closed Erlenmeyer-like flask reservoir containing 220 mL of water placed above the level of the reaction vessel. The details of our experimental arrangement for measuring the production of oxygen in the BL system were designed in our previous work …”

“…We were able to calculate the rates of oxygen evolution and to study the effects of the stirring rate on the rate of oxygen production and on the oscillations in the BR reaction. In our earlier papers on the BL reaction, , we showed that the rate of interphase transport of I 2 and O 2 can be greatly influenced by stirring and that such physical processes can inhibit oscillations.…”

“…First, the oscillatory parameters are changed. The period of oscillations is increased to several minutes, and the oscillations in the rate of oxygen production can be followed relatively easily, as described in our earlier paper concerning the Bray−Liebhafsky reaction. Second, the evolution of CO 2 , which might be a gaseous product in the case of malonic acid and which is not included in the models, is ruled out for acetone.…”

Numerical Simulation of the Behaviors of the Bray-Liebhafsky Oscillating Chemical Reaction by a Four-variable Model

“…Although a large number of works [11][12][13][14] devoted to the mechanism of the BL reaction for a long time, the overall mechanism has still not been elucidated, and is complicated by the fact that the system is also sensitive to light [15], pressure and stirring [16,17], microwaves [18,19] and oxygen [20,21]. It seems to be too difficult to obtain enough relevant information on the kinetics of this system.…”

Computational Simulation of Bray-Liebhafsky (BL) Oscillating Chemical Reaction

“…However, one process might be faster than the other during a short interval. Processes (B) and (C) alternately dominate over the whole system and result in the concentration of iodine and the rate of oxygen gas evolution change periodically [9][10][11][12]. Although the overall stoichiometry of the BL reaction seems to be simple, it is not easy to describe the mechanism.…”