Oxidation Process of Xylene in Air Under Electron Beam Irradiation with TiO2 and Ag/TiO2

Oxidation of xylene and its organic irradiation byproducts in air using plasma-driven catalyst (PDC: TiO₂ and Ag/TiO₂) pellet layers was studied under electron beam (EB) irradiation. The layers were placed in an irradiation or a non- irradiation space in order to distinguish the oxidation of xylene/byproducts by EB irradiation, by catalytic process, and by a combination of the two. The oxidation reactions on the surface of the PDC pellets were also extracted by means of the difference in the concentrations of xylene and byproducts in the presence of the PDC layer or a non-catalyst (stainless-steel) layer with the same volume. For irradiated xylene/air mixtures, xylene was exclusively decomposed in the gas phase in an irradiation space. Introduction of the PDC layer to an irradiation space resulted in the suppression of xylene decomposition. On the other hand, production of CO₂ was observed in the gas phase of an irradiation space and on the surface of the PDC pellets placed in irradiation and non-irradiation spaces. The concentration of CO₂, produced in the gas phase and on the PDC pellet surface, became higher when the layer was placed in the vicinity of an irradiation space. The production of CO₂ is enhanced by loading of Ag to the TiO₂ pellet surface. The highest concentration of CO₂ was obtained for Ag/TiO₂ with Ag contents greater than 5wt%. The production of CO₂ from byproducts on the PDC pellet surface was evaluated from the difference in the concentrations of xylene and byproducts between the PDC and the SUS pellet layers.