A study of sensitized explosions. IV. The carbon monoxide-oxygen reaction catalysed by nitrogen peroxide

Abstract

The work of Hadman, Thompson and Hinshelwood (1932 a, b ) has shown that the reaction between pure carbon monoxide and oxygen is characterized by a region of ignition above 650° C, bounded by upper and lower critical pressure limits outside which the rate of oxidation falls to negligibly small values in the dry gases. Sagulin, Kowalsky, Kopp and Semenoff (1930) have reported that the region of ignition of moist carbon monoxide is extended more than 200° C towards lower temperatures in the presence of 0.1% nitrogen peroxide, although larger concentrations than this exert an anti-catalytic effect. Another aspect of the catalytic influence of nitrogen peroxide on the carbon monoxide-oxygen reaction is revealed by the work of Crist and Roehling (1935) and Crist and Calhoun (1936), who have found that steady reaction occurs in nitrogen peroxide sensitized mixtures at 527° C and 750 mm. total pressure. The rate of reaction varies with concentration of nitrogen peroxide in a manner shown by curve B in fig. 1, which has been taken from the paper by Crist and Roehling (1935). This graph, as shown by Crist and Roehling (1935), can be represented as the sum of two simpler curves A and C , depicting respectively distinct catalytic functions of nitrogen peroxide. Curve C was shown to be explained by a mechanism in which nitrogen peroxide, by alternate oxidation and reduction, plays the part of an oxygen carrier in accordance with the following formal equations: CO + NO 2 = CO 2 + NO, 2NO + O 2 = 2NO 2 .