The plasma enhanced surface reactions in a packed bed dielectric barrier discharge reactor

The conversion and utilization of CO2 is one of the greatest global challenges. Plasma assisted catalysis provide a new resolution to this problem. However, the energy efficiency and conversion rates of the plasma process are still insufficient for industrial applications. The key reasons are the highly complex interaction between gaseous plasma and catalytic materials, especially in packed bed dielectric barrier discharges. Our study fills this critical gap by developing a novel numerical approach to study how the ns pulse driving plasma trigger the heterogeneous reactions on the Ni/gamma-Al2O3 catalyst surface. The development of plasma inside the reactor is in the form of surface ionization wave (SIW) + filamentary microdischarges. The high electron power in the SIW region and the high ion power density in the sheath region on the catalysts surface provide enough energy to trigger heterogenous reactions. The heterogeneous reactions not only generate the local high CO density region near the Ni/gamma-Al2O3 surface, but also increases the space averaged density of CO. The extension of activation time of catalytic material can significantly increase the conversion efficiency of CO2.