(69c) Characteristics and Kinetics of Decomposition of CO2 In a Dielectric-Packed Discharge Reactor

The characteristics of carbon dioxide decomposition in a dielectric-packed barrier discharge reactor have been studied in the present work. A variety of factors including dielectric materials, input energy and electrode length for the decomposition of CO₂ were examined. To further understand the reaction mechanism of CO₂ decomposition in dielectric barrier discharge plasma, the oxidation of CO in plasma was also investigated. It showed that both the presence of dielectric materials and the increase of input energy promote decomposition of carbon dioxide. Dielectric materials induce the enhancement of electric field strength, resulting in increase of average electron energy, which is favorable for electron impact reactions, and surfaces of dielectric materials play an important role in the combination of oxygen radicals, favoring the conversion of CO₂. In a hollow reactor, keeping other conditions constant, the electrode length does not affect the conversion of CO₂, whereas in a dielectric-packed reactor, the conversion of CO₂ increases with the increase of electrode length. Kinetics study showed that the decomposition of CO₂ as well as the oxidation of CO in hollow or packed plasma reactors are all first-ordered.