Temperature dependence of plasma-catalysis using a nonthermal, atmospheric pressure packed bed; the destruction of benzene and toluene

A nonthermal, atmospheric pressure, packed-bed plasma reactor has been used to study the effect of temperature on the plasma-catalytic destruction of toluene and benzene in air. The plasma reactor was packed with BaTiO3 beads to which TiO2, gamma-Al2O3, and Ag, Pt, or Pd impregnated catalysts were added. The reactor can be heated up to similar to 500 degrees C, and the destruction efficiencies for toluene and benzene were determined for plasma alone, catalyst alone, and the combined plasma-catalyst configuration. Comparisons have been made to determine the relative contributions of the catalyst and plasma and to discover any synergistic effects. Plasma-catalysis shows greater destruction than catalysis alone with increasing temperature for both benzene and toluene. Catalysis alone has a threshold temperature of similar to 300 degrees C for the destruction of toluene and benzene, but plasma-catalysis with Pd- and Pt-impregnated alumina achieves > 95% destruction at this temperature and has a threshold of similar to 100 degrees C. Toluene is more easily destroyed than benzene at all temperatures, by all catalysts.