Nonthermal plasma chemical processing assisted by catalysis and adsorption

Nonthermal plasma reactions assisted by catalysis or adsorption were investigated by using a reactor packed with ceramic pellets, mainly BaTiO3, mixed with catalyst or adsorbent pellets. The reaction conducted was the decomposition of benzene in air at atmospheric pressure and at room temperature. Using the pellets without a catalyst or adsorbent, the decomposition activity was increased with an increase in the dielectric constant of the pellets and the byproducts of CO and N2O were revealed to be produced from lattice oxygen of the pellets. In catalyst-hybrid reactors packed with a mixture of BaTiO3 and Al2O3 or metal catalyst on Al2O3, the decomposition gave the reduction of byproducts such as CO and N2O. In adsorbent-hybrid reactors packed with a mixture of BaTiO3 and Molecular Sieves, the formation of NOx was reduced. Based on the formation of the main product of CO2, a remarkable increase of the decomposition activity was found in the adsorbent-hybrid reactors while a slight increase in the catalyst-hybrid reactors. The decomposition energy efficiency in the adsorbent-hybrid reactor could be improved if the adsorption and plasma discharge were carried out cyclically at optimized intervals.