Microreactors for Syngas Conversion to Higher Alkanes: Effect of Ruthenium on Silica-Supported Iron-Cobalt Nanocatalysts

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• 作者：Shihuai Zhao ; Venkata S. Nagineni ; Naidu V. Seetala ; Debasish Kuila
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2008
• 出版时间：March 5, 2008
• 年：2008
• 卷：47
• 期：5
• 页码：1684 - 1688
• 全文大小：275K
• 年卷期：v.47,no.5(March 5, 2008)
• ISSN：1520-5045

文摘

The effect of ruthenium (Ru, 0.4 wt %) as a promoter on silica-supported iron and cobalt nanocatalysts (~3wt % each) for syngas (H₂ and CO) conversion to higher alkanes was studied in a silicon microreactor.Fe-Co/SiO₂ catalysts with and without Ru were synthesized by a sol-gel methods. The high specific surfacearea (325 m²/g) from BET analysis can be attributed to the porous structure of silica supported by its SEMimages. The FE-STEM image indicated that the catalyst particle size is <10 nm. The magnetic studies of Cocatalysts using a vibrating sample magnetometer suggest that Ru does not influence the reduction of cobaltoxide to cobalt, the active form of Co catalysts in silica. The highest conversion of CO (~78%) was observedwith a Ru-Fe-Co/SiO₂ catalyst at 220 s/entities/deg.gif">C, 1 atm, total flow rate of 0.4 sccm, and H₂/CO ratio of 3:1 inmicroreactors containing 25 s/entities/mgr.gif">m channels. The addition of Ru to the Fe-Co/SiO₂ catalyst increased COconversion by 16% but lowered selectivity to propane by 10%. The catalysts remained active after 25 h ofreaction, although the magnetic properties indicated that ~85% of metal nanoparticles formed non-ferromagneticspecies.