The combustion of aromatic and alicyclic hydrocarbons. III. Ignition and cool-flame characteristics

Abstract

In a previous communication (Burgoyne 1937), attention was drawn to certain apparently anomalous features of the slow combustion of n -butyl benzene, and it was shown, inter alia , that the observed irregularities in the temperature coefficient of the reaction could be accounted for by the occurrence of cool-flame ignitions of the same type as those exhibited by the higher aliphatic hydrocarbons (Townend and Chamberlain 1936). These circumstances suggested that a general survey of the ignition characteristics of the aromatic hydrocarbons would be desirable as an aid to elucidating the mechanism of their combustion; and the present paper embodies the results for the series previously studied, together with two members of the alicyclic series which have been included to serve as a connecting link with the paraffins and olefines. Owing to the wide variations in reactivity towards oxygen of the compounds in question, it was found impracticable to employ the same experimental technique throughout the series; for whilst the ignitions of the more reactive members could safely be studied in silica and glass vessels, the remainder involved high pressures and required the use of steel apparatus. Comparative experiments, however, showed that no essential alteration in the ignition characteristics resulted from the substitution of one material for the other.