The formation and destruction of hydrogen cyanide from atmospheric and fuel nitrogen in rich atmospheric-pressure flames

摘要: Abstract A novel method involving direct sampling of natural flame ions into a mass spectrometer has been used to measure the concentration HCN, NH 3 and NO in atmospheric-pressure flames. It is found that HCN formed from N 2 reaction zone rich hydrocarbon flames subsequently completely oxidized within flame, part NO. This corresponds Fenimore's ‘prompt NO’. The amount proportional concentration, but not very dependent on nature fuel (CH 4 , C H ) or temperature (between 2000 2560 K). varies strongly with equivalence ratio greater, richer flame. In contrast nitrogen compounds fuel, whatever their (NO, CH CN pyridine), are converted quantitatively subsequent disappearance studied, between 2300 K rate consistent + OH → NCO being rate-limiting step constant approximately 1 × 10 −10 cm molecule −1 s although other mechanisms may be important at lower temperatures.