Non-Oxidative Ethane Dehydrogenation in a Packed-Bed DBD Plasma Reactor

Abstract

Plasma-assisted conversion of ethane (C2H6) can produce value-added chemical building blocks using green electricity. Here we employ a simple packed-bed coaxial dielectric barrier discharge (DBD) reactor to convert C2H6 at mild operating conditions unattainable by conventional thermocatalysis. Ethylene (C2H4), acetylene (C2H2), and methane (CH4) are the main products along with small fractions of C3 and C4 hydrocarbons. Interestingly, the C2H4 selectivity is primarily correlated to C2H6 conversion, dominated by electron dissociation and recombination reactions irrespective of the dielectric properties of the packed bed material (SiO2, Al2O3, ZrO2, TiO2, and BaTiO3), packing material size, supplied power, and C2H6 concentration. While a distortion of the electric field and discharge propagation results in varying dissipated power as materials change, the C2H4 energy yield remains constant. The particle size appears to affect conversion mainly due to pressure alterations. Pd/SiO2 catalyst can change the selectivity, favoring saturated species by expending hydrogen.