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

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 show that 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 flow rate 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 flow rate 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 H_α active particles with the experimental parameters was obtained. The possible generation path of hydrogen is predicted by combining with the discharge mechanism.