Plasma-induced methane catalytic cracking: Effects of experimental conditions.

Low-carbon conversion of hydrocarbon fuels and feedstocks, as well as the macroscopic production of H 2 , are central focus in the advancement of high-value and efficient conversion of CH 4. The effects of Ar addition ratio, discharge power and temperature on the results of plasma methane cracking were investigated on a dielectric barrier discharge (DBD) plasma experimental system. The results show that the addition of Ar can improve the methane conversion, and the optimal ratio of CH 4 conversion to H 2 production after the effect is CH 4 : Ar = 1:1, at which the methane conversion reaches 49.62% and the H 2 selectivity reaches 52.66%. The plasma at 25 °C can make the methane conversion close to the effect of catalytic cracking at 600 °C, while the H 2 selectivity is lower, the H 2 generation is 32.59% lower than the latter, and the products have more C 2 –C 4 hydrocarbon impurities. The solid byproduct resulting from the DBD plasma cracking of methane primarily consisted of carbon black, possessing an average particle size of 62.21 nm. The incorporation of Ar and the amplification of power augment the CH* radical intensities, which suggests both conditions contribute positively to the dissociation of the CH 4 molecule. [Display omitted] • The optimal ratio of CH 4 to Ar stands at 1:1. • Plasma operating at 25 °C can mimic the catalytic thermal cracking effect at 600 °C. • The generation of the solid-phase product, carbon black is induced by the plasma. • An increase in the C 2 –C 4 product is observed under plasma activity. [ABSTRACT FROM AUTHOR]