Study On Catalytic Decomposition Of Carbon Dioxide By Dielectric Barrier Discharge Plasma

With more and more serious global climate change and environmental pollution,an action plan for peak carbon dioxide emissions and carbon neutral is proposed for implemented.As the most direct and simple reaction for CO₂ utilization,CO₂decomposition could not only greatly reduce CO₂ emissions,but also obtain key chemical material CO.Plasma Technology offers an approach for CO₂ decomposition being conducted at room temperature and atmospheric pressure.Dielectric Barrier Discharge（DBD）plasma was adopted to study CO₂decomposition.The reactor was designed and optimized firstly.At the discharge gap 2mm,copper foil as the external electrode and the aluminum rod as the internal electrode,there was a better CO₂ decomposition performance due to enhancement of the discharge plasma and CO₂ conversion was 10.1%.Different oxides including alkali oxides,ceramic oxides and molecular sieves were packed in the DBD plasma reactor and the CO₂ decomposition was tested.Among them,Al₂O₃obtained a higher CO₂ conversion of 15.1%that is 1.5 times the value in the empty plasma reactor,which was attributed to the larger specific surface area,pore volume and better low-temperature adsorption performance of Al₂O₃.As for supported catalyst,Ni O/Zr O₂ treated by H₂ and plasma was better than that of the untreated sample with CO₂ conversion being increased from was 10.9%to 13.0%.Perovskite catalysts such as MgTiO₃,CaTiO₃,Sr Ti O₃ and Ba Ti O₃ were prepared by molten salt method.Among them,the Mg Ti O₃ exhibited best activity with the highest CO₂ conversion achieved due to the combined effects of better low-temperature adsorption performance,bigger grain sizes and higher dielectric constant of the dielectric.The Mg Ti O₃ with different grain sizes were obtained by different calcination temperatures and synthesis methods,while CO₂ conversion had a positive relation with the grain size of Mg Ti O₃.The accumulated channels formed between the Mg Ti O₃ with larger grain sizes were beneficial for enhancing discharge plasma and then increased CO₂ conversion.