Steam electrolysis with simultaneous production of C2 hydrocarbons in a solid electrolyte cell

• Published in: International journal of hydrogen energy 2014-01, Vol.39 (2), p.675-683
• Main Authors: Kyriakou, V., Garagounis, I., Stoukides, M.
• Format: Article
• Language: English
• Subjects: Alternative fuels. Production and utilization; Anodes; Applied sciences; Cathodes; Conversion; Electrodes; Electrolysis; Electrolytic cells; Energy; Exact sciences and technology; Fuels; Hydrocarbons; Hydrogen; Hydrogen production; Methane; Methane coupling; Solid electrolyte cells; Steam electrolysis
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2013.10.129

The production of hydrogen from steam electrolysis with simultaneous conversion of methane to C2 hydrocarbons was investigated. The reaction system was studied in a solid state oxygen ion (O2−) conducting cell at temperatures between 700 °C and 840 °C. Methane and steam, diluted in nitrogen, were introduced over the anode (Ag) and the cathode (Pt), respectively. When oxygen was electrochemically “pumped” from the cathode to the anode, steam was electrolyzed to produce gaseous H2 and CH4 was converted to C2H4, C2H6 and CO2. The conversion of methane and the C2 yield increased when a perovskite of the form SrZr0.95Y0.05O3−a (SZY) was placed on the anodic electrode to serve as a methane coupling catalyst. At the anode, C2 yields exceeding 7.6% were obtained, while an up to 65% H2 yield was achieved at the cathode. [Display omitted] •An O2− conducting cell producing C2s and H2 from CH4 and H2O was demonstrated.•Addition of a CH4 coupling catalyst over the anode improved C2 yield by 60%.•An up to 65% of steam feed was electrolyzed on the Pt cathode.