Controlling Parameters in the Efficiency of Hydrogen Production via Electrification with Multi-Phase Plasma Processing Technology

Abstract

A nanosecond pulsed non-equilibrium plasma reactor is used to crack hydrocarbons into hydrogen and lighter intermediates at atmospheric pressure and warm temperature. The effects of power, capacitance, breakdown voltage, pulsing frequency, energy per pulse, and carrier gas type are investigated for product generation. Multiple gaseous products including hydrogen and hydrocarbons are calculated and compared at different conditions. A statistical analysis is performed on hydrogen yield for different experimental conditions to determine the significance of the studied parameters. Comparable hydrogen yields are produced when using methane (4 to 22 g-H2/kWh) as a carrier gas as compared to argon (7 to 14 g-H2/kWh). Although, notably, the methane carrier is more selective to hydrogen and sensitive to other operating parameters, the argon is not. Statistical analysis shows that plasma power, capacitance, and energy per pulse appear to influence hydrogen yield while pulsing frequency and breakdown voltage do not. A higher yield of hydrogen is achieved with low plasma power and a low energy per pulse, with a low capacitance for both cases of pure CH4 and pure Ar. The results show that low plasma power based on a low energy per pulse of <10 mJ is preferable for hydrogen production in a batch reactor. This CO2-free hydrogen production method produces hydrogen from fossil fuels at less than USD 2/kg in electricity.