Oscillatory glow

Linnett and various co-workers [57, 58] also observed oscillatory glow, somewhat intermittently, in their studies of the reaction with extensively-dried reactants (see above) in vessels with untreated surfaces. These authors unfortunately used the phrase multiple explosions to describe the phenomenon which they observed only by eye. Later, meticulous work exploiting instrumental monitoring of the reaction by Bond et al. [59, 60] revealed that the ignition limit reported by the Linnett group on the basis of a detectable emission actually corresponds to the limit for steady glow. 

Fig. 5.30. Representative trains of oscillatory glow for CO + O2 mixtures in a closed system (a) chloropicrin-treated reactor with p = 33 Torr, = 841 K giving a total of 94 oscillations over 3 hr (b) and (c) light emission and reactant consumption in a clean reactor with p = 22 Torr and T, = 900 K. (Reprinted with permission from reference [60], Royal Society...

Fig. 5.31. The co-existence of (a) steady glow and (b) oscillatory glow for the CO -I- O2 reaction (dry mixtures) in an ageing reactor. (Reprinted with permission from reference [60], Royal Society of London.)...

Steady and oscillatory glow responses occupy separate regions of the parameter plane under continuous flow conditions. It is possible that the flow of reactants in the period before the reaction is monitored (and this period must be rigorously reproduced in any given set of experiments if reproducible results are to be obtained) provides a consistent degree of surface conditioning in such experiments [65]. Oscillatory glow, which is... 

THE GLOW REACTION IN THE CARBON MONOXIDE-OXYGEN SYSTEM AND ITS RELATION TO THE EXPLOSION REGION OSCILLATORY BEHAVIOUR... 

With an alumina coated vessel (but not with silica), Linnett et al. [511] also observed oscillatory behaviour inside the glow region. Instead of a single glow corresponding with reaction, they observed a series of successive glows, and these were particularly numerous in CO-rich mixtures. Linnett et al. worked with moist gases. However, similar oscillatory... 

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