Mechanism study on gliding arc (GA) plasma reforming: Reaction and energy pathways for H2 production from methanol steam reforming

Abstract

Aiming on deeply understanding the gliding arc methanol steam reforming (GA-MSR), its reaction mechanism was studied in terms of reaction and energy transfer pathways by combining experiment and plasma kinetics simulation in CH3OH concentration (CME) range of 5%-100%. Via monitoring the consumption and production rates of each species, the roles of species play during GA-MSR are revealed. The important reactive species are identified as H, OH and CH3, which induce the main dehydrogenation pathway of CH3OH→(CH2OH + CH3O) → CH2O → HCO → CO for CH3OH converting to syngas. With the increase of CME, the concentrations of H and CH3 are enhanced, but OH concentration is weakened. The concentration variation trends of the important reactive species regulate that CO2 by-produces at low CME and hydrocarbons do at high CME. In addition, the energy pathways, which are very important but always ignored for plasma reforming, are disclosed advancedly for the energy-strongly coupling GA-MSR. The positive effect of CME on the energy transfer from plasma to chemical energy and the major energy loss pathway of heat loss are uncovered. The energy pathways studies also show why a very high energy efficiency (>80%) could be achieved in GA-MSR, which could be further improved by avoid energy loss from the system.