电工技术学报2025，Vol.40Issue(21)：6832-6843,12.DOI:10.19595/j.cnki.1000-6753.tces.241853
磁场增强介质阻挡放电CO2分解反应研究
CO2 Decomposition in Dielectric Barrier Discharge Enhanced by Magnetic Field
摘要
Abstract
Direct CO2 decomposition is a typical form to convert CO2 into valuable chemical feedstocks and fuels.However,stringent reaction conditions are required in the conventional methods due to the intrinsic thermal stability of CO2,which frequently result in suboptimal conversion and energy efficiencies.Low-temperature plasma technology(e.g.,dielectric barrier discharge,DBD)offers a highly reactive environment for the activation and conversion of CO2.CO2 decomposition in DBD has been a hot topic,but its reaction performance is still not satisfactory.Introducing an external magnetic field into DBD can enhance discharge intensity,and consequently improve the performance for practical applications,which presents an innovative approach to improve CO2 decomposition performance.Nonetheless,there is limited research on the effects of magnetic fields on the discharge characteristics of DBD and the corresponding CO2 decomposition performance.The optimization of reaction parameters has yet to be clearly established,and underlying mechanisms have not been deeply understood.Herein,a comprehensive investigation has been performed on CO2 decomposition in DBD enhanced by magnetic field. The DBD reactor comprises the stainless steel inner rod and outer mesh electrodes,the NdFeB ring magnet,and the quartz dielectric tube.It is powered by a nanosecond pulsed power supply.The outer electrode is grounded after connected to a reference capacitor.Voltage and current measurements are obtained using a Tektronix high voltage probe,a Pin-tech voltage probe and a Pearson current coil,respectively.All signals are recorded using a Tektronix digital oscilloscope.Electrical characteristics are derived from voltage-current waveform analysis and the equivalent circuit model of DBD.An Andor spectrometer has been employed to identify the type and intensity of reactive species within the discharge space.Additionally,a Fotric thermal imaging device has been utilized to quantify temperature variations outside the reactor during discharge.The discharge characteristics has been discussed based on the results of electrical,optical and temperature characteristics.A PANNA gas chromatography has been utilized to analyze the gaseous components before and after the reaction.Reaction performance has been evaluated based on the conversion of CO2 to CO and the overall process energy efficiency. The following conclusions can be drawn from the study:(1)In the coaxial DBD system for the direct CO2 decomposition,increasing the voltage amplitude results in a significant enhancement in discharge power.Introducing a magnetic field leads to further improvements in total power and energy utilization efficiency of the power supply.In the presence of a magnetic field,the peak value of the gap voltage and the energy utilization efficiency have been achieved at the voltage amplitude of 24 kV.(2)The presence of a magnetic field enhances the discharge intensity and promote the production of energetic electrons and other reactive species,which increases their possibility of collisions with CO2 molecules,leading to the increase in both CO2 conversion and CO yield.Introducing the magnetic field leads to the largest enhancement of 14.9%for CO2 conversion when the voltage amplitude is 22 kV,while the largest enhancement for CO yield(11.9%)at the voltage amplitude of 20 kV.(3)The positive influence of magnetic field on CO2 decomposition surpasses the negative influence of the resulted heat loss,which promotes the overall energy efficiency while increasing CO2 conversion.The maximum energy efficiency of 0.101 mmol/kJ is achieved at an input voltage amplitude of 18 kV,which is increased by 6.4%compared to that obtained in the absence of a magnetic field.Further enhancement in the process energy is expected to be achieved by the optimization of the operating parameters and the development of suitable catalysts.关键词
外部磁场/介质阻挡放电/CO2直接分解/放电特性/能量效率Key words
External magnetic field/dielectric barrier discharge/direct CO2 decomposition/discharge characteristics/energy efficiency分类
信息技术与安全科学引用本文复制引用
吕锡昂,马添翼,梅丹华,陈慧敏,方志..磁场增强介质阻挡放电CO2分解反应研究[J].电工技术学报,2025,40(21):6832-6843,12.基金项目
国家自然科学基金面上项目资助(52177149). （52177149）
