Effect of catalyst composition and reactor configuration on benzene oxidation with a nonthermal plasma-catalyst combined reactor

Plasma-catalysis system comprising surface discharge reactor (SDR)and catalysts were constructed and tested for benzene decomposition. In benzene oxidation with SDR, benzene conversion and the amount of COx formed monotonically increased with input energy, but the benzene decomposition behavior was not related with ozone formation. The loading of metal oxides, Al₂O₃, TiO₂ and CeO₂ in SDR greatly promoted benzene oxidation and CO₂ formation. The highest activity was obtained with manganese oxides dispersed on ultrastable zeolite Y (Mn/USY). In the range of low input power, the amount of ozone formed increased with the input power, and ozone can be efficiently consumed in benzene oxidation by loading the Mn/USY catalyst in the latter part of SDR. In the higher power range where the amount of ozone decreased with increasing the power, the loading of Mn/USY catalyst inside the reactor was more effective because not only ozone but also short-lived species formed in SDR were utilized for benzene oxidation. The addition of water vapor to reaction gas did not affect benzene conversion and COx formation with SDR-Mn/USY catalyst system. The preadsorbed benzene on the Mn/USY catalyst can be oxidized to CO₂ with high selectivity compared with homogeneous oxidation of benzene in SDR.