High-Temperature Co-Electrolysis of Carbon Dioxide and Steam for the Production of Syngas; Equilibrium Model and Single-Cell Test.

O'Brien, J. E. ; Stoots, C. M. ; Herring, J. S. ; Hartvigsen, J. J.

Technical Information Center Oak Ridge Tennessee

关键词: Hydrogen production;    Carbon dioxide;    Steam;    Syngas;    Electrolysis;   

RP-ID  :  DE2007912907

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

This paper presents results of recent experiments conducted at the INL studying coelectrolysis of steam and carbon dioxide in a 10-cell high-temperature solid-oxide electrolysis stack. Coelectrolysis is complicated by the fact that the reverse shift reaction occurs concurrently with the electrolytic reduction reactions. All reactions must be properly accounted for when evaluating results. Electrochemical performance of the stack was evaluated over a range of temperatures, compositions, and flow rates. The apparatus used for these tests is heavily instrumented, with precision mass-flow controllers, on-line dewpoint and CO2 sensors, and numerous pressure and temperature measurement stations. It also includes a gas chromatograph for analyzing outlet gas compositions. Comparisons of measured compositions to predictions obtained from a chemical equilibrium co-electrolysis model are presented, along with corresponding polarization curves. Results indicate excellent agreement between predicted and measured outlet compositions. Coelectrolysis significantly increases the yield of syngas over the reverse water gas shift reaction equilibrium composition. The process appears to be a promising technique for large-scale syngas production.