The oscillating Fischer-Tropsch reaction

• 成果类型: Article
• 署名作者: Zhang, Rui; Wang, Yong; Gaspard, Pierre; Kruse, Norbert
• 署名单位: Washington State University; United States Department of Energy (DOE); Pacific Northwest National Laboratory; Universite Libre de Bruxelles; Universite Libre de Bruxelles
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10449
• DOI: 10.1126/science.adh8463
• 发表日期: 2023-10-06
• 页码: 99-103
• 关键词: co hydrogenation; higher alcohols; cobalt carbide; surface-areas; lower olefins; catalysts; mechanism; STABILITY; kinetics; BEHAVIOR

摘要

The mechanistic steps that underlie the formation of higher hydrocarbons in catalytic carbon monoxide (CO) hydrogenation at atmospheric pressure over cobalt-based catalysts (Fischer-Tropsch synthesis) have remained poorly understood. We reveal nonisothermal rate-and-selectivity oscillations that are self-sustained over extended periods of time (>24 hours) for a cobalt/cerium oxide catalyst with an atomic ratio of cobalt to cerium of 2:1 (Co2Ce1) at 220 degrees C and equal partial pressures of the reactants. A microkinetic mechanism was used to generate rate-and-selectivity oscillations through forced temperature oscillations. Experimental and theoretical oscillations were in good agreement over an extended range of reactant pressure ratios. Additionally, phase portraits for hydrocarbon production were constructed that support the thermokinetic origin of our rate-and-selectivity oscillations.