在高密度超临界介质中,在碳支持的铁基催化剂上在现场形成的碳化物上的化
Tatiana V Bogdan1,2, Aleksey E Koklin1, Igor I Mishanin1
1Laboratory of Heterogeneous Catalysis and Processes in Supercritical Media, N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences (ZIOC RAS), Leninsky Prospect, 47, 119991, Moscow, Russia.
ChemPlusChem
|July 16, 2024
概括
碳载体上的铁基催化剂通过化有效地将二氧化碳转化为有价值的C2+碳化合物. 这项研究强调了铁碳化物在菲舍-托普施合成中对于增强C2+选择性的关键作用.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 二氧化碳化通常产生二氧化碳或甲,但碳化合物产量有限.
- 从二氧化碳中产生更高的碳化合物是可持续化学合成的理想选择.
- 在碳支上的铁基催化剂被研究用于二氧化碳转化.
研究的目的:
- 为了研究基于碳的铁基催化剂 (Fe,FeCr,FeK) 上的二氧化碳化.
- 了解催化剂结构和活性相在产品选择性中的作用.
- 为了从CO2中获得C2+碳化合物的高选择性.
主要方法:
- 使用XRD,TEM,XPS,Mössbauer光谱和现场磁力学进行催化剂表征.
- 在超临界条件下 (400°C,8.5MPa) 进行的CO2化反应.
- 对反应产物的分析,以确定各种碳化合物和二氧化碳的选择性.
主要成果:
- 螺旋式氧化物阶段 (Fe3O4, γ-Fe2O3, Fe1+xCr2-xO4) 仅生产了CO.
- 铁碳化物,在费舍-托普施合成中活跃,在Fe-和FeK-催化剂上形成.
- 在超临界条件下,20Fe1K/C催化剂实现了对C1-C12+碳化合物的72%选择性.
- 缺乏铁碳化物的FeCr/C催化剂产生了90-100%的CO选择性.
结论:
- 铁碳化物对于通过费舍尔-托普施合成通过二氧化碳化实现对C2+碳化合物的高选择性至关重要.
- 催化剂的组成和预激活对于形成活性铁碳化物至关重要.
- 碳支持的铁催化剂,特别是FeK,显示出有效的二氧化碳转化为有价值的碳化合物的巨大潜力.
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