Simultaneous production of H2 and C2 hydrocarbons by using a novel configuration solid-electrolyte + fixed bed reactor

Abstract

A novel combined single chamber solid electrolyte plus fixed bed reactor configuration was developed for the simultaneous production of H2 and C2 hydrocarbons from a humidified CH4 atmosphere. Hence, a Pt/YSZ/Ag solid electrolyte cell was placed on the top of an active oxidative coupling catalyst powder bed Ce–Na2WO4/SiO2. H2 was produced via steam electrolysis in a Pt cathode of the solid electrolyte cell (H2O + 2e− → H2 + O2−). Simultaneously, the produced O2− ions were electrochemically pumped to the Ag anode, leading to the C2s production, via oxidative coupling of CH4 (4CH4 + 3O2− → C2H4 + C2H6 + 3H2O + 6e−). Additionally, non-reacted O2− molecules desorbed to the gas phase (2O2− → O2+4e−) and reacted with CH4 in the catalyst bed leading to an increase of C2s yield. The influence of different reaction parameters was investigated together with long-term reaction experiments, confirming the stability of this configuration for its practical application. The obtained results demonstrated that the addition of an active catalyst bed strongly enhances both: the efficiency of the single chamber steam electrolysis and the oxidative coupling process.