Plasma-induced methane catalytic cracking: Effects of experimental conditions

Low-carbon conversion of hydrocarbon fuels and feedstocks, as well as the macroscopic production of H2, are central focus in the advancement of high-value and efficient conversion of CH4. 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 CH4 conversion to H2 production after the effect is CH4: Ar = 1:1, at which the methane conversion reaches 49.62% and the H2 selectivity reaches 52.66%. The plasma at 25 degrees C can make the methane conversion close to the effect of catalytic cracking at 600 degrees C, while the H2 selectivity is lower, the H2 generation is 32.59% lower than the latter, and the products have more C2-C4 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 CH4 molecule.