Investigation of low-pressure flames of a number of compounds containing sulfur by the ESR method

Abstract

Low-pressure flames of H 2 S, CS 2 , sulfur and COS vapors have been studied by the ESR method. High concentrations of atomic hydrogen, oxygen, and SO and OH radicals were discovered in the hydrogen sulfide flame. It has been established that the combustion of hydrogen sulfide proceeds in two steps. Initially hydrogen sulfide is, oxidized to the intermediate compounds SO and H 2 . After the consumption of H 2 S and SO, which are inhibitors for the hydrogen oxidation, combustion of H 2 starts, accompanied by the formation of OH radicals and H and O atoms. High concentrations of atomic oxygen and SO radicals were discovered in the rarefied flames of CS 2 mixtures with O 2 rich in oxygen, α=(O 2 )/(CS 2 ) ⋍2.5 It has been shown that, near the point α-2.5, the concentration of atoms is the greatest, while that of SO radicals is the least. It has been established that such a behavior of O atoms and SO radicals is connected with the reaction O+COS=CO+SO. SO radicals and very high concentrations of O atoms were found in the low-pressure flames of sulfur vapor amounting to 30% of the initial O 2 . A considerable amount of O atoms and SO radicals were detected in the flame of COS mixtures with O 2 .