IONIC REACTION-MECHANISMS IN PRE-MIXED FLAMES DISCLOSED BY STABLE-ISOTOPE LABELING

The methane-oxygen fuel system was investigated using deuterium labell ing methods. The pre-mixed-flames were burnt on a simple quartz burner and sampled directly by a VG PlasmaQuad instrument, which consists of a quadrupole mass spectrometer equipped with a high-temperature molec ular beam inlet. The genesis of the predominant ions C3H3+ and C2H3Oand their eventual routes of decomposition are discussed. The proposed mechanisms are supported by thermochemical considerations and appropr iate tandem mass spectrometric experiments on alternatively generated ions.