Carbon dioxide reforming of methane at near room temperature in low energy pulsed plasma

The reforming of methane by carbon dioxide was studied in a pulsed plasma reactor. The products mainly consisted of syngas and C-2 hydrocarbons. Compared to the previous similar works, the electrical pulse energy injected into the reactor was much lower, 5-8 mJ, while the frequency was increased up to 5 kHz. At these low energy densities, the chemical energy efficiency was appreciably improved. The latter was higher than 30% throughout the experiments while reached the maximum of about 55% at the reactants ratio CO2/CH4 = 3. Although, the reactor temperature was typically 70 degrees C, the hydrogen production efficiency of at least 50% was achieved. The better performance at lower energy densities is attributed to the fast saturation of the molecular dissociation rate by the excitation level or equivalently by the pulse energy. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.