1. Insight into gliding arc (GA) plasma reduction of CO2 with H2: GA characteristics and reaction mechanism
- Author
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Ai-Min Zhu, Jing-Lin Liu, Xiao-Song Li, and Jing-Bao Liu
- Subjects
Electron density ,Reaction mechanism ,Range (particle radiation) ,Materials science ,Acoustics and Ultrasonics ,Plasma parameters ,Analytical chemistry ,02 engineering and technology ,Plasma ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Spectral line ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Arc (geometry) ,Electron temperature ,0210 nano-technology - Abstract
As an intermedia between cold and thermal plasmas, warm plasma generated by gliding arc (GA) discharge possesses high conversions and high energy efficiencies for CO2 conversion. However, there is little understanding for the arc characteristics in CO2-based atmosphere and reaction mechanism of CO2 in GA plasma from experimental approach. For this purpose, a magnetically driven GA plasma with a constant length of arc is designed to study GA characteristics and reaction mechanism by changing H2/CO2 molar ratio (from pure CO2 to pure H2). In the entire range of H2/CO2 ratio, the arc channel shows a glow-like feature. The plasma parameters are arc temperature of 2200–3600 K, electron density of ~1.6 × 1014 cm−3 and electron temperature of ~3 eV. From pure CO2 to pure H2, arc diameter decreases from 1.3 to 0.6 mm, whereas rotational frequency increases from 20 to 64 Hz. Based upon the optical emission spectra of CO, OH, H and O species, chemluminescence spectra of CO and O recombination and CO production rate detected online by gas chromatographs, the reaction mechanism at low and high H2/CO2 molar ratios is disclosed.
- Published
- 2019