Study of hydrocarbons conversion in air using an homogeneous pre-ionised discharge

A photo-triggered discharge was used to study plasma kinetic processes involved in ethene and propene conversion in the air-like gas mixture (20% O-2) at a total pressure of 400 mbar, at ambient temperature, and for a specific deposited electrical energy less than 20 J/L. Initial concentration value of hydrocarbon molecules ranged from 800 up to 2700 ppm. Hydrocarbons and by-products concentrations at the reactor exit were monitored using FTIR spectroscopy. Owing to the medium homogeneity, experimental results were compared to a self-consistent 0D-model taking into account all relevant reactions for the gas mixtures under investigation. It appeared that, in conditions of the experiment, the removal of ethene is due to partial oxidation by reaction with oxygen atoms and ozone molecules, and also by reactions with OH radicals which are produced in the afterglow. Reactions with O were dominating processes for propene.