Hybrid plasma-thermal system for methane conversion to ethylene and hydrogen

By combining dielectric barrier discharge plasma and external heating, we exploit a two-stage hybrid plasma-thermal system (HPTS), i.e., a plasma stage followed by a thermal stage, for direct non-oxidative coupling of CH4 to C2H4 and H2, yielding a CH4 conversion of ca. 17 %. In the two-stage HPTS, the plasma first converts CH4 into C2H6 and C3H8, which in the thermal stage leads to a high C2H4 selectivity of ca. 63 % by pyrolysis, with H2 selectivity of ca. 64 %.