Photolysis of azomethane–propane mixtures. Arrhenius parameters for the hydrogen abstraction reactions of methyl with azomethane and with propane

Abstract

Mixtures of up to 14% azcjmethane in propane have been photolyzed using mainly 366 nm radiation in the ranges of 323-453 K and 25-200 torr. Detailed measurements were made of the yields of nitrogen, methane, and ethane. Other products observed were isobutane, n-butane, ethene, and propene. A detailed mechanism is proposed and shown to account for the observed variation of product yields with experimental conditions. The quantum yield of the molecular processis found to be given by the temperature-independent equationThe values of rate constants obtained are log k3(cm3/mol sec) = 12.03 f 0.15 -40.8 f 1.1 kJlmoll(2.3RT) log k4(cm3/mol sec) = 11.42 f 0.15 -40.7 f 1.1 kJlmoll(2.3RT) where the reactions are (3) (4)and it is assumed that the rate constant for the reactionis given by log k5(cm3/mol sec) = 13.4

High Temperature Reactions of CH3 2. H‐Abstraction from Alkanes

“…These authors, however, were not concerned with any possibilities of structure changes of the glass during the reaction. It has already been confirmed that the stoichiometric glass is stable below the glass transition region (T,) and crystallization occurs on long time heating above 700°C [8,9]. However, this is not the case for nonstoichiometric glasses, which are expected to be produced during the reduction.…”