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

Abstract

The effect of ruthenium (Ru, 0.4 wt %) as a promoter on silica-supported iron and cobalt nanocatalysts (∼3 wt % 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 surface area (325 m2/g) from BET analysis can be attributed to the porous structure of silica supported by its SEM images. The FE-STEM image indicated that the catalyst particle size is <10 nm. The magnetic studies of Co catalysts using a vibrating sample magnetometer suggest that Ru does not influence the reduction of cobalt oxide to cobalt, the active form of Co catalysts in silica. The highest conversion of CO (∼78%) was observed with a Ru−Fe−Co/SiO2 catalyst at 220 °C, 1 atm, total flow rate of 0.4 sccm, and H2/CO ratio of 3:1 in microreactors containing 25 μm channels. The addition of Ru to the Fe−Co/SiO2 catalyst increased CO conversion by 16% but lowered selectivity to propane by 10%. The catalysts remained active after 25 h of reaction, although the magnetic properties indicated that ∼85% of metal nanoparticles formed non-ferromagnetic species.

Bimetallic Nanocatalysts in Mesoporous Silica for Hydrogen Production from Coal-Derived Fuels

“…The stability of the PdNi bimetallic catalyst is superior to that observed in our previous studies in sol-gel matrix with Fe-Co-Ru catalysts for Fischer-Tropsch reactions and Co or Ni catalysts for the SRM reactions. In both cases, the sol-gel encapsulated catalysts deactivated more easily [1]. The current results are indeed significant and suggest the stability of the Pd-Ni catalyst in mesoporous silica.…”

“…Coal is gasified to produce syngas which is condensed using F-T catalysts to yield methanol and light hydrocarbons [1,2] which are further processed into gasoline and diesel.…”

“…Catalytic SRM for hydrogen production using conventional macroscale reactors [4,5] and microreactors [1,6] is well known in literature. Most of the commercial catalysts available for steam reforming reactions are not environmentally viable due to their high carbon monoxide conversion.…”

Kinetics of Fischer–Tropsch Synthesis in a 3-D Printed Stainless Steel Microreactor Using Different Mesoporous Silica Supported Co-Ru Catalysts

“…Therefore, the selection of support and study of its interaction with the incorporated metal ion plays an important role in catalysis. In our previous studies, sol-gel encapsulated catalysts were used in silicon microreactors for FT synthesis [37][38][39]. While Al 2 O 3 and SiO 2 sol-gel supports show similar behavior in formation of higher alkanes such as ethane, propane, and butane for the reactions at 1 atm, TiO 2 has a profound effect on FT synthesis [40] and the stability of the catalysts are observed in reverse order from that observed with SiO 2 and Al 2 O 3 .…”

Bimetallic nanocatalysts in mesoporous silica for steam reforming reactions to produce H2 for fuel cells

“…Methanol is the most suitable source of H2 due to its availability, high H/C ratio, easy production, and can be conveniently stored and also transported for in-situ H2 production [1]. Catalytic steam reforming of methanol (SRM) for H2 production using conventional macroscale reactors [2,3] and microreactors [4,5] has been investigated before. Most of the commercial catalysts available for steam reforming reactions (SRRs) are not environmentally viable due to their high carbon monoxide conversion.…”