Study on the dehydrogenative coupling of methane in a thermal diffusion column reactor

In order to realize efficient conversion of methane, thermal diffusion column reactor was used to dehydrogenative coupling of methane. C₂ to oily products were observed. Due to the thermal diffusion effect, the direction of flow of methane into the vertically set reactor has a great influence on methane conversion and Q product's selectivity. It is found that downward flowing results in a higher C₂ product's selectivity. At the carbon pyrogen surface temperature of 1470 K, methane conversion was about 36%, C₂ product's selectivity reached 40%, in which the molar percentage of acetylene and ethylene was above 95%. Addition of hydrogen into methane greatly increased the C₂ product's selectivity. At the molar ratio of H₂/CH₄ = 1/2, C₂ product's selectivity was promoted up to 68.3%, meanwhile methane conversion remained at a high level of 23%. A large amount of hydrogen was produced from the dehydrogenation of methane. At the carbon pyrogen temperature 1470 K, molar percentage of hydrogen of more than 40% was measured in the effluent gas out of dehydrogenation of downward flowing methane.