Experimental and modeling study of the oxidation of acetaldehyde in an atmospheric-pressure pulsed corona discharge

摘要

This paper reports the results obtained for the degradation of acetaldehyde by an atmospheric plasma corona discharge working in a pulsed regime. It was shown that a few hundred ppm of acetaldehyde diluted in a pure N _2 gas flow can be removed up to 80% by a discharge fed with an electric power lower than 1W. Under the same conditions, adding up to 5% of O _2 allowed the removal of up to 95% of the initial acetaldehyde. The main identified end products were CO _2, CO and methanol. A quasi-homogeneous zero-dimensional chemical model was developed to investigate the respective efficiency of the discharge and post-discharge periods in the global removal of the pollutant. The identified main pathways of acetaldehyde degradation were quenching of N _2 metastable states during plasma pulses and oxidation by O and OH radicals during the post-discharge. This latter contribution increased with input power because of ozone accumulation in the gas mixture acting as an additional oxygen reservoir.