Plasma catalytic collaborative decomposition of methanol to hydrogen production

Abstract

A novel plasma-assisted methanol decomposition kinetic model is developed through experimental investigations which can reasonably predict the species concentration at different voltages. The methanol decomposition does not occur at 600 K without plasma, whereas it initiates at 450 K under plasma conditions. This is attributed to the new reactions between the high-energy electrons and Ar∗ with the methanol under the electric field. However, under plasma alone, H₂ selectivity is low as the formation of CH₃, which decreases the fluxes of H-abstraction reactions, such as CH₂OH + HCH₂O + H₂. With plasma-catalyst, 15 % increase in H₂ selectivity and 12 % increase in CH₃OH conversion are achieved at 493 K and methanol tends to be converted more to CH₃O than to CH₂OH or CH₃ compared with plasma alone, which increases the CH₃O adsorbed on the surface of catalyst, facilitating the chain reaction (CH₃O→CH₂O→CO + H₂) and inhibits the conversion of CH₃O/CH₂OH to CH₃ and CH₂ by plasma, and as a result, the CH₃OH conversion rate and H₂ yield rate increase.