Detailed Characterization of 2-Heptanone Conversion by Dielectric Barrier Discharge in N2 and N2/O2 Mixtures

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Molecules, spectroscopy, kinetics, environment, & general theory, 2010-01, Vol.114 (1), p.397-407
• Main Authors: Chiper, Alina Silvia, Blin-Simiand, Nicole, Heninger, Michel, Mestdagh, Hélène, Boissel, Pierre, Jorand, François, Lemaire, Joël, Leprovost, Julien, Pasquiers, Stéphane, Popa, Gheorghe, Postel, Christian
• Format: Article
• Language: English
• Subjects: A: Atmospheric, Environmental and Green Chemistry
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp907295d

The products of 2-heptanone conversion by dielectric barrier discharge plasma are analyzed under different conditions: alternating current (ac) or pulsed mode of excitation, variable energy, variable composition of the carrier gas. The efficiency of the conversion is higher using a pulse excitation mode than an ac mode. With a small oxygen percentage (about 2−3%) added to nitrogen, 2-heptanone is about 30% more efficiently removed than in pure nitrogen, while the 2-heptanone removal decreases with an oxygen percentage higher than 3%. A new analysis method, based on chemical ionization mass spectrometry, is used for volatile organic compound detection along with chromatography. Several products issued from 2-heptanone conversion with ac excitation are identified in nitrogen and in air, and a chemical scheme is proposed to explain their formation and their treatment by the discharge. It appears that byproducts are issued not only from oxidation reactions, but also from C−C bond cleavage by collisions with electrons or nitrogen excited states.