PULSED DBD-CATALYST HYBRID REACTOR FOR ENVIRONMENTAL CLEAN-UP: VOCS OXIDATION IN AIR AT LOW TEMPERATURE
Résumé
The combination of pulsed dielectric barrier discharge with palladium supported on alumina catalysts (0.5 and 1 wt%Pd) was investigated for the oxidation of volatile organic compounds (CH4, C3H6, and C7H8) in air at atmospheric pressure, temperature up to 500°C, and input plasma energy up to 145 J/L. The plasma-catalysis interaction revealed the benefit effect of the plasma on the CH4, C3H6, and C7H8 oxidation even at low temperature leading to high selectivity in CO2 than only-plasma reaction. At room temperature, the plasma could activate both alumina and Pd/Al2O3 catalysts. For such systems, the light-off curves were shifted toward lower temperatures as the plasma input energy increased. At a given energy, the plasma-catalyst was helpful in minimizing the by-products formation. At low temperature, these mechanisms could be explained by the plasma-induced interactions between reactive species and catalyst active sites whereas at higher temperature the thermal processes become predominant overtaking the contribution of the plasma-activated processes.