Identification of oxygenated ions in premixed flames of dimethyl ether and oxygen

The structure of characteristic flame-ions in premixed flames of dimethyl ether and oxygen was studied by ion-molecule reactions with ammonia and collision activation with argon. The results obtained show that the flame-ions m/z 45 and m/z 47 are the methoxymethyl cation, CH3OCH2+, and protonated dimethyl ether, (CH3)(2)OH+. The flame-ion m/z 61 is a mixture of the trimethyloxonium ion, (CH3)(3)O+ and lesser amounts of protonated methyl formate and/or protonated ethyl methyl ether. The viability of an ionic mechanism to soot formation for dimethyl ether-oxygen flames is discussed on the background of ions present in the dimethyl ether flames and the reactivity of the ions.