Mechanism of Autoignition in Benzene-Air Mixtures '6.. J. LEVEDA4HL
A. BECKERS Technische Hochschule, Aachen, Germany
.Yational Rureair of Standards, Washinlrton, D . C .
L T H O U G H considerable research has been done on the slow oxidation of benzene, the rapid autoignition reactions occurring a t higher temperatures and pressures have not been thoroughly investigated. T h e present work on benzene-air autoignition indicates t h a t this reaction can be approximately described b y a second-order rate equation with low activation energj-, arid t h a t the benzene molecule degrades t o acct)-lenes and oxidized products. T h e first experiments were conducted with a rapid compression machine (2) t o obtain a n espression relating the rate of reaction t o the temperature and partial pressures of the reactants. T h e machine was developed under the direction of F. -1.F. Schmidt, Institut fur Warmetechnik und 1-erbrennungsniotoren, Technische Ilochschule, Aachen. Homogeneous fuel-air mixtures TTere compressed rapidly t o temppratures and pressures on the order of 800" K. and 20 atni. T h e succeeding combustion occurred a t constant volume in a few milliseconds, n-hile pressure was continuously recorded. An esperiment t o detect the reaction products of partial autoignition of benzene was carried out in :I single-cylinder, variable-compression-ratio C F I i ciigine (21, from which the spark plug had been removed anti which promoted reaction by compressing the premised charge t o a high temperature and pressure of ahout 900" I
