燃料化学学报（中英文）2025，Vol.53Issue(10)：1482-1499,18.DOI:10.1016/S1872-5813(25)60554-8
Pt改性FeZn催化剂提升常压CO2-FTS反应合成α-烯烃的稳定性研究
Study on the enhancement of stability in ambient pressure CO2-FTS for the production of α-olefins by Pt-modified FeZn catalysts
摘要
Abstract
The CO2-FTS under ambient pressure for α-olefins synthesis offers advantages such as safety,lower operating cost,and saving equipment investment.However,the reaction has encountered challenges including high selectivity for CO and CH4,as well as poor catalyst stability.To address these issues,Cu,Co,Ru,and Pt-modified FeZn catalysts were designed and synthesized for the ambient pressure CO2-FTS reaction.The results show that the introduction of Pt significantly improves the stability of CO2 conversion,reducing the selectivity for by-products CO and CH4,and promoting the formation of valuable C2+hydrocarbon products.When optimized content of 6％Pt was incorporated into the FeZn catalyst,the CO2 conversion rate increased from 22.5％to 27.3％,and no obvious deactivation was observed over 20 h.Correspondingly,the average selectivity for CO and CH4 decreased obviously from 93.1％and 52.9％to 80.0％and 20.5％,respectively.Especially,when the H2/CO2 ratio was increased from 3 to 7,CO2 conversion enhanced up to 48.6％,CO selectivity sharply decreased to 24.0％,and at the same time,the selectivity for C2+hydrocarbon products increased noticeably.More importantly,the undesired selectivity to CH4 was further lower toward about 13.1％,high α-olefins content was achieved like 90％C=2-C=4in the C2-C4 hydrocarbon fraction,and the selectivity to CO and CH4 became stable.Characterization results from XRD,H2-TPR,CO-TPD,CO2-TPD,H2-D2 exchange,TEM,Raman,XPS and MES indicate that the introduction of Pt significantly enhances the adsorption and dissociation of CO,as well as the dissociation of H2,thus promoting the hydrogenation and coupling of surface CO* species to form C2+hydrocarbons and reducing the carbon deposits.It should be mentioned that the addition of Pt into FeZn catalyst has eliminated the formation of graphite carbon and reduced the thickness of amorphous carbon layer around the iron carbide nanoparticles.Moreover,Pt improves the carbonization ability of Fe species in the catalyst,increases the content of the active phase x-Fe5C2 for FTS,and decreases the crystaline size of x-Fe5C2 particles.关键词
CO2加氢/常压/α-烯烃/Pt助剂/H2/CO2比Key words
CO2 hydrogenation/ambient pressure/α-olefins/Pt promoter/H2/CO2 ratio分类
化学化工引用本文复制引用
李章师,李玉峰,何环环,王长旭,刘冰,刘小浩..Pt改性FeZn催化剂提升常压CO2-FTS反应合成α-烯烃的稳定性研究[J].燃料化学学报（中英文）,2025,53(10):1482-1499,18.基金项目
This project was supported by the National Key Research and Development Program of China(2023YFB4103201)and the National Natural Science Foundation of China(22379053).国家重点研发计划(2023YFB4103201)和国家自然科学基金(22379053)资助 （2023YFB4103201）
