Effect of filling materials on CO2 conversion with a dielectric barrier discharge reactor

Recently, CO2 decomposition technology has attracted great attention. The direct product of CO2 conversion using the DBD plasma technology is CO. This technology can reduce CO2 emissions and achieve economic benefits. In order to further improve the conversion and energy efficiency, the effect of filled dielectric materials (layered double hydroxides and their derivatives, quartz wool, TiO2, MgO, CaO) on the CO2 discharge performance and reaction performance was investigated. The results indicated that the CO2 conversion and energy efficiency were significantly higher than that of the non-packed reactor. The filling of dielectric materials can not only increase the gas residence time and the conversion, but also change the discharge model to improve energy efficiency. The dielectric constant, pore structure and acid-base properties of the dielectric materials also affected the CO2 decomposition. Among several packing materials, the CO2 conversion and energy efficiency of the filled MgO reactor were the highest. Under the experimental conditions, when the input power was increased from 30 W to 60 W, the conversion increased from 14.9% to 23.6% and the energy efficiency decreased from 8.9% to 6.1%. This is because MgO has abundant pore structure, appropriate dielectric constant and alkaline active sites. The main adsorption of CO2 on MgO is chemical adsorption, which is conducive to the decomposition of CO2.