Extreme management strategy and thermodynamic analysis of high temperature H2O/CO2 co-electrolysis for energy conversion. (January 2022)

• Record Type: Journal Article
• Authors: Qi, Huiying; Zhang, Junfeng; Tu, Baofeng; Yin, Yanxia; Zhang, Tonghuan; Liu, Di; Zhang, Fujun; Su, Xin; Cui, Daan; Cheng, Mojie
• Is Part Of: Renewable energy. Volume 183(2022)
• Page Start: 229
• Page End: 241
• Publication Date: 2022-01
• Subjects: Solid oxide electrolysis cell -- Co-electrolysis -- Syngas -- Conversion -- Carbon deposition; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2021.10.096
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: H2 O/CO2 co-electrolysis through solid oxide electrolysis cell (SOEC) combined with renewable energy system and Fischer-Tropsch system to produce fuels is a promising way to convert electrical energy into chemical energy. In this work, fuel composition, conversions of H2 O and CO2, selectivity to H2, CO and CH4, and yields of H2, CO and CH4 for H2 O/CO2 co-electrolysis are investigated based on the thermodynamic equilibrium under the boundary condition without carbon deposition. High selectivity to CH4 can be reached at suitable MH2O /MCO2 ratio and low temperature, while high selectivity to CO and H2 can be reached at high temperature according to the thermodynamic equilibrium results. When the operating temperature of SOEC is low, the conversions of H2 O and CO2 cannot reach high due to carbon deposition, which can be improved by increasing MH2O /MCO2 ratio. When the operating temperature of SOEC is high, the conversions of H2 O and CO2 can reach high without carbon deposition, which can be higher than 90% at 1073 K according to the thermodynamic equilibrium results. The syngas with different H2 /CO ratios for Fischer-Tropsch synthesis of different fuels can be produced by selecting appropriate co-electrolysis condition. Highlights: Fuel composition, conversion, selectivity and yield for SOEC are investigated. High H2 O/CO2 ratio should be used to avoid carbon deposition at low temperature. High CH4 selectivity can be reached at suitable H2 O/CO2 ratio and low temperature. Different syngas can be produced by selecting suitable operating condition of SOEC. High CO selectivity can be reached by co-electrolysis at high temperature.