Abstract:
A kind of rotating gliding arc (RGA) argon plasma co-driven by tangential flow and magnetic field was investigated and used for hydrogen production from methane decomposition.In order to obtain insights into the physical characteristics of the RGA plasma, optical emission spectroscopy (OES) analysis was used to determine the electron temperature and electron density.In addition, the effects of feed flow rate and CH
4/Ar ratio on the performance of the methane decomposition process in this RGA plasma were also investigated.Results have shown that, the RGA plasma is a kind of unique plasma between thermal and non-thermal plasma, with electron temperature of 1.0-2.0 eV and electron density of 10
15 cm
-3.In this system, the CH
4 conversion could be 22.1%-70.2% and it increased with the increase of flow rate or CH
4/Ar ratio.The H
2 selectivity varied from 21.2% to 61.2%, and with the augment of flow rate, the H
2 selectivity first varied slightly and then increased.A comparison of different non-thermal plasmas (e.g., microwave, radio frequency, and dielectric barrier discharge) showed that the RGA plasma could provide a relatively high CH
4 conversion and H
2 selectivity, as well as a relatively low energy consumption for H
2 production, while maintaining a high flow rate (i.e., processing capacity) of 6-20 L/min.