Effect of SO2 on the chain reaction of hydrogen oxidation: Intermittent flames

Conjugated processes of the chemical transformation of sulfur dioxide under the effect of chain gas-phase reactions

“…One such analysis was per formed in [12] using the phenomenology of intermit tent flames. Solving a system of differential equations over all active centers H, O, and OH with and without reactions (e) and (j) in the quasi stationary approxi mation yields the same equation ( 4 ) Reactions (1)-(4) determine the principal model of the process responsible for self ignition.…”

“…An interesting result was obtained [9,10] for the chain oxidation of hydrogen with SO 2 additives at the same temperatures but at low pressures in the range of the spontaneous ignition of hydrogen-oxygen mix tures. Under these conditions, the leading active cen ters are H and O atoms and OH radicals rather than НО 2 radicals, and sulfur dioxide is transformed into elemental sulfur [9,10].…”

“…Under these conditions, the leading active cen ters are H and O atoms and OH radicals rather than НО 2 radicals, and sulfur dioxide is transformed into elemental sulfur [9,10]. At the same time, sulfur diox ide does not react in a hydrogen medium with no oxy gen at these temperatures (450-500°С).…”

“…At certain rates of gas flow through the reac tor, the continuous flame mode becomes the so called intermittent flame mode of consecutive self ignitions [9,10]. This is obviously a new kinetic manifestation of branched chain reactions.…”

“…In this work, we studied the effect SO 2 has on the dynamics of the spontaneous combustion of hydrogenoxygen mixtures using a procedure for detecting the flashes of light [12] that accompany spontaneous igni tion. The results were analyzed using the theory of branched chain reactions and data on the chemical conversion of SO 2 under the effect of chain reactions of hydrocarbon oxidation and slow hydrogen oxidation.…”