Oxidation of carbon monoxide by methoxy-radicals

Abstract

The thermal decomposition of dimethyl peroxide (DMP) in a static system was investigated over the temperature range 123–153°C at varying pressures of carbon monoxide. The reaction of methoxy-radicals with carbon monoxide produces carbon dioxide and methyl radicals. The rate constant of reaction (2) CH₃O·+ CO [graphic omitted] CO₂+ CH₃(2) was determined to be: k₂/l. mol^–1 s^–1= 10^{10.2 ± 0.6} exp–(11.800 ± 1500/RT)(R in cal mol^–1 K^–1).

At low carbon monoxide pressures production of carbon dioxide is first order in carbon monoxide and half order in DMP while at high carbon monoxide pressures (> 120 Torr) it is zero order in carbon monoxide and first order in DMP. At high pressures of carbon monoxide and at 127°C reaction (2) is the main reaction of methoxy-radicals.

These data are rationalized by a simple free-radical mechanism.