Steam reforming of methane in a gliding arc discharge reactor to produce hydrogen and its chemical kinetics study

[Display omitted] •A GAD reactor was used for SMR for hydrogen production.•The characteristics of OES in the SMR plasma process were investigated.•A 0-D chemical kinetic model was developed to describe the SMR plasma process.•The H atom plays a major role in CH4 conversion and H2 production.•The reaction pathways and mechanisms in the SMR plasma process were clarified. A knife-type gliding arc discharge plasma reactor was developed for steam-methane reforming (SMR) H2 production. The kinetic model was established for industrial application. The effects of steam to carbon molar ratio, residence time and input power on SMR reactions were investigated. The experimental results indicated the S/C molar ratio of 2.01, the residence time of 13.8 s, and the input power of 36.0 W, the energy yield of hydrogen reached 173.6 L·(kW·h)−1, H2 and CO were also identified as the main gaseous products. Optical emission spectroscopy was used to diagnose chemically active species in plasma processes. The corresponding zero-dimensional chemical kinetic model was established, which includes 166 electron impact reactions and heavy particle reactions. The calculated results were in good agreement with the experimental results. The model results revealed the reaction CH4 + H → CH3 + H2 initiated by the H atom was the dominant reaction of CH4 conversion, and was also the main way of H2 generation.