介质阻挡放电等离子体甲烷/水蒸气重整制氢

Hydrogen production from methane/steam by dielectric barrier discharge plasma reforming

采用自制的介质阻挡放电实验系统,进行了甲烷/水蒸气大气压下重整制氢实验研究。考察了水碳比(水蒸气/甲烷物质的量比)、气体总流量、放电电压和放电频率对甲烷转化率及氢气等主要产物产率的影响。结果表明,甲烷转化率和氢气产率随着水碳比和放电电压的增加而增大,随着气体总流量和放电频率的增加呈现先增大后减小的变化规律。在放电电压18.6 k V、放电频率9.8 k Hz、水碳比3.4、反应气体总流量79 mL/min时,获最大氢气产率(14.38%)。此外,利用发射光谱对放电过程中的活性基团进行了原位诊断,得到了CH~·、OH~·、H_2及H_α活性粒子的光谱信号强度随实验参数的变化规律,并结合放电机理推测了氢气的生成路径。

The hydrogen production by methane/steam reforming at atmospheric pressure was investigated by using a self-made dielectric barrier discharge experimental system. The effect of water/carbon ratio( steam/methane molar ratio),total gas flow,discharge voltage and discharge frequency on the methane conversion,hydrogen and other major product yields was examined. The experimental results showthat the methane conversion rate and hydrogen yield increase with the increase of water carbon ratio and discharge voltage,and the methane conversion rate and hydrogen yield increase first and then decrease with the increase of total gas flowrate and discharge frequency. The maximum hydrogen yield( 14.38%) can be obtained at the discharge voltage of 18. 6 kV,discharge frequency of 9. 8 kHz,water/carbon ratio of 3. 4,and total reaction gas flowrate of 79 mL/min. In addition, The active group in the discharge process was diagnosed by in-situ emission spectroscopy,and the changing trend in the spectral signal intensity of CH·,OH·,H2 and Hα active particles with the experimental parameters was obtained. The possible generation path of hydrogen is predicted by combining with the discharge mechanism.