Rhodium‐Catalyzed Methanation and Methane Steam Reforming Reactions on Rhodium–Perovskite Systems: Metal–Support Interaction

Abstract

Metal–support interaction in rhodium–perovskite systems was studied using LSF (La0.6Sr0.4FeO3−δ) and STF (SrTi0.7Fe0.3O3−δ) supports to disentangle different manifestations of strong or reactive metal–support interaction. Electron microscopy and catalytic characterization in methane steam reforming/CO2 methanation reveal that reduction in hydrogen at 673 K and 873 K causes different extents of Fe exsolution. Depending on the perovskite reducibility, Fe–Rh alloy particles are observed. No signs of strong metal–support interaction (i.e., encapsulation of metal particles) by reduced oxide species were observed. As re‐oxidation in oxygen at 873 K did not fully restore the initial structures, the interaction between Rh and the perovskites manifests itself in irreversible alloy formation. Catalytic effects are the suppression of methane reactivity with increasing prereduction temperature. The results show the limits of the strong metal–support interaction concept in complex metal–oxide systems.

Noble-metal-free and Pt nanoparticles-loaded, mesoporous oxides as efficient catalysts for CO2 hydrogenation and dry reforming with methane

“…The produced SNG is easy to store and can be transported in existing natural gas pipelines. A variety of transition metals such as Ni [44][45][46], Co [47][48][49], Pd [50,51], Ru [52][53][54], Rh [55,56] have been widely investigated as active components for CO 2 methanation.…”

Structural investigations of La0.6Sr0.4FeO3−δ under reducing conditions: kinetic and thermodynamic limitations for phase transformations and iron exsolution phenomena

“…In order to obtain a spectrum of pure FeO (being prone to disproportionation into Fe and Fe 3 O 4 ), iron(II) oxalate (FeC 2 O 4 ) was thermally decomposed using the in situ heating stage within the spectrometer chamber by heating it to a temperature of 573 K. Further details are given in a previous work. 17 Transmission electron microscopy images were collected by a 200 kV JEOL analytical high-resolution electron microscope equipped with an energy-dispersive X-ray spectrometer (EDX) and an electron energy-loss spectrometer (EELS).…”

“…Simultaneous Thermal Analysis (STA) was conducted in an STA 409 PC LUXX (Netzsch, Germany) device under Air, He and 5% H 2 in Ar using 100 mg of sample powder that was placed in alumina crucibles. The released gaseous species (m/z ¼ 2, 16,17,18,44) were analyzed simultaneously in an OMNi Star GSD 320 mass spectrometer (Pfeiffer Vacuum, Germany). Fig.…”

Impacts of SiC Carrier and Nickel Precursor of NiLa/support Catalysts for CO2 Selective Hydrogenation to Synthetic Natural Gas (SNG)

“…In the recent years, methane has been considered as a promising energy source due to its clean nature, high calorie value and combusting efficiency . It is apparent that CO 2 should be considered as main carbon source for methane (CO 2 +4H 2 →CH 4 +2H 2 O) concerning the less consumption of fossil fuels .…”