Catalysis Today, Vol.351, 103-112, 2020
Nanosecond pulse plasma dry reforming of natural gas
CO2 conversion into value-added chemicals and fuels is one of the greatest challenges of human society. Plasma-assisted catalysis is an emerging and rapidly expanding field of research offering promising solutions to this problem. However, conversion rates and energy efficiency of the plasma processes remain insufficient for widespread industrial adoption. The key reasons are highly-complex and ultra-fast reaction kinetics in the gas phase and at the interface with catalytic and supporting materials, which form intricate 3D micro-porous structures, especially in packed bed dielectric barrier discharge (PB-DBD). Our work fills this critical gap in knowledge by developing a novel simulation approach to maximize the conversion rates and energy efficiency of the ns pulse driving PB-DBD based on precise studies of plasma dynamics with sub-ns and sub-mu m resolution. The high instantaneous power leads to the expansion of plasma is in the form of surface ionization waves coupled with filamentary microdischarges. The strong electron dissociation reaction in these discharge region results in CO and H-2 density of ns pulse PB-DBD are higher than those of other approaches to plasma catalysis. The extremely low duty cycle of ns pulse also decreases the backward recombination reaction. Therefore, the conversion rate and the energy efficiency of plasma catalysis are improved. This approach is generic, is validated by experimental results, and can be applied to other plasma catalysis systems.