Low temperature oxidation of high levels of CO and gas phase hydrocarbons (HCs) emissions, as created by HCCI-like combustion engines, has been investigated. Performances of commercial Euro5 Diesel oxidation catalyst (DOC, Pt-Pd/Al2O3) were evaluated by determining its light-off temperature when it is placed downstream of a pilot-scale multi-DBDs reactor powered by an AC generator delivering an average power in the range 50-300 W. DOC performances with and without plasma have been systematically compared under various operating conditions (input energy density, space velocity, flow rate, temperature). Results demonstrate the capability of the plasma to lower the DOC light-off temperature (T50) for CO and HCs. Improvement of T50 by about 60°C was obtained and could explained through chemical exothermic mechanisms involving the plasma species over the active catalytic sites. This approach show that DOC and plasma work synergistically to promote selectively HCs oxidation at low temperature. C3H6 exhibit the high oxidation rate followed by C7H8, C10H22, and CH4.
