Methane, photolytic decomposition

Ozin and co-workers 157) suggested that the photoinduced activation of methane by Cu atoms in 12 K matrices to produce CuH, CH3, CUCH3, and H atoms proceeds via a mechanism which involves the photolytic decomposition of the intermediate HCUCH3. This complex was not isolated but was identified by its IR and ESR spectra. The authors suggested that Cu—CH3 bond homolysis to give CuH and CH3 radicals is the principal mode of photodecomposition. 

X lO M/sec at 25°C) [82,83]. This presumably explains both the slow rate of photolytic decomposition under strictly anaerobic conditions as well as the marked acceleration of the photolytic decomposition rate in the presence of air due to trapping of the radicals by oxygen. In the latter case the final products are cobalt(III) (i.e. aquocobalamin from methylcobalamin) and formaldehyde, with traces of methanol, methane and formic acid. 

Decomposition. Acetaldehyde decomposes at temperatures above 400°C, forming principally methane and carbon monoxide [630-08-0]. The activation energy of the pyrolysis reaction is 97.7 kj/mol (408.8 kcal/mol) (27). There have been many investigations of the photolytic and radical-induced decomposition of acetaldehyde and deuterated acetaldehyde (28—30). 

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