基于MIL-68(Al) 的工程催化剂,在低温下对二氧化碳和一氧化碳的化具有高稳定性
Saeideh Salimi1, S Morteza F Farnia1, Kamran Akhbari1
1School of Chemistry, College of Science, University of Tehran, P.O. Box 14155-6455 Tehran, Iran.
Inorganic chemistry
|October 19, 2023
概括
这项研究使用MOF模板策略开发了高效的中孔酸催化剂,用于二氧化碳转化. 最好的催化剂实现了92.4%的二氧化碳转化,展示了增值化学生产的有前途途途.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 通过催化化来减少大气中的二氧化碳并将其转化为有价值的化学物质是一个关键的全球挑战.
- 金属有机框架 (MOFs) 提供高表面积和可调节结构,使它们成为催化剂合成的有前途平台.
研究的目的:
- 为二氧化碳化合成高效和稳定的中孔类催化剂.
- 研究和铁纳米粒子 (NP) 负载和分布对催化性能的影响.
- 探索MIL-68的实用性,作为催化剂制备的模板.
主要方法:
- 用MIL-68 (((Al) 作为前催化剂合成中孔类催化剂,封装Ni或Ni-FeNP.
- 使用PXRD,BET-N2,TEM,FE-SEM,ICP-OES,EDX-map,CO2-TPD,H2-TPR和H2-TPD等技术进行催化剂物理化学性质的表征.
- 在各种条件下对CO2甲化反应的催化性能进行评估.
主要成果:
- 促进的催化剂 (含Fe) 的颗粒大小和孔径较小,Ni NP分布均.
- 铁的促进促进了二氧化碳吸附/激活和减少过程, CO2-TPD 和 H2-TPR 证明了这一点.
- 5Fe·15Ni@Al2O3 MIL-68(Al) 催化剂表现出卓越的性能 (92.4%的转换率,在350°C时99.6%的选择性) 和降低的激活能量 (42.5 kJ mol-1).
- 这两种催化剂类型都表现出高稳定性 (>100小时) 和在250°C时完全将CO化为CH4.
结论:
- MOF模板策略在创建稳定,高性能CO2甲化催化剂方面非常有效.
- 增强的催化活性归因于NP均分布,强烈的金属支相互作用,以及酸物种的形成.
- 开发的催化剂为将二氧化碳转化为甲提供了可行的途径,甲是一种有价值的化学原料.
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