Rh‐promoted YZr‐supported Ni catalyst (5Ni/YZr) is investigated for DRM and characterized with X‐... more Rh‐promoted YZr‐supported Ni catalyst (5Ni/YZr) is investigated for DRM and characterized with X‐ray diffraction, Raman, infrared spectroscopy, cyclic reduction–oxidation–reduction temperature programmed experiment, thermogravimetry, and transmission electron microscope. Over 5Ni/YZr, some active sites become inactive under the CO2 stream and limit H2 yield to ∼71%. Upon 4 wt% Rh addition over 5Ni/YZr; more than one type of stable active sites (Rh and Ni) generates, moderate basic sites are enhanced, wide ranges of CO2‐interacted surface species (especially bidentate CO2‐adsorbed species) are grown and graphitic carbon proportion over spent catalyst declines. This resulted in 87.35% H2 yield and 86.73% CO yield up to 420 min. 5Ni4Rh/YZr catalyst maintains ∼80% H2 yield at the end of 27 h of DRM reaction.
A better understanding of the reaction mechanism and kinetics of dry reforming of methane (DRM) r... more A better understanding of the reaction mechanism and kinetics of dry reforming of methane (DRM) remains challenging, necessitating additional research to develop robust catalytic systems with high catalytic performance, low cost, and high stability. Herein, we prepared a zirconia-alumina-supported Ni-Fe catalyst and used it for DRM. Different partial pressures and temperatures are used to test the dry reforming of methane reaction as a detailed kinetic study. The optimal reaction conditions for DRM catalysis are 800°C reaction temperature, 43.42 kPa CO2 partial pressure, and 57.9 kPa CH4 partial pressure. At these optimal reaction conditions, the catalyst shows a 0.436 kPa2 equilibrium constant, a 0.7725 m o l C H 4 /gCat/h rate of CH4 consumption, a 0.00651 m o l C H 4 /m2/h arial rate of CH4 consumption, a 1.6515 m o l H 2 /gCat/h rate of H2 formation, a 1.4386 molCO/gCat/h rate of CO formation. This study’s findings will inspire the cost-effective production of robust catalyti...
Finding a robust catalytic system for hydrogen production via dry reforming of methane (DRM) rema... more Finding a robust catalytic system for hydrogen production via dry reforming of methane (DRM) remains a challenge. Herein, MNi0.9Zr1−xYxO3 (M = Ce, La, and La0.6Ce0.4; x = 0.00, 0.05, 0.07, and 0.09) catalyst was prepared by the sol–gel method, tested for DRM and characterized by surface area and porosity, X‐ray diffraction, H2‐temperature programmed reduction, thermogravimetry, and transmission electron microscopy. In La0.6Ce0.4NiO3 catalyst, the substitution of Ni by 0.1% Zr results in a constant high catalytic activity (83% hydrogen yield at 800°C) due to the presence of reducible “NiO‐species interacted strongly with the support” (stable metallic Ni over reduced catalyst) and redox input by ceria phase for laying instant lattice oxygen during lag‐off period of CO2. Substitution of Ni by Zr and Y in the CeNiO3 catalyst system nurtures Ni3Y (providing highly stable metallic Ni for CH4 decomposition) and cerium yttrium oxide phases (providing strong redox input). CeNi0.9Zr0.01Y0.09O...
Samarium oxide (Sm2O3) is a versatile surface for CO2 and H2 interaction and conversion. Samarium... more Samarium oxide (Sm2O3) is a versatile surface for CO2 and H2 interaction and conversion. Samarium oxide-supported Ni, samarium oxide-supported Co-Ni, and samarium oxide-supported Ru-Ni catalysts were tested for CO2 methanation and were characterized by X-ray diffraction, nitrogen physisorption, infrared spectroscopy, H2-temperature programmed reduction, and X-ray photoelectron spectroscopy. Limited H2 dissociation and widely available surface carbonate and formate species over 20 wt.% Ni, dispersed over Sm2O3, resulted in ~98% CH4 selectivity. The low selectivity for CO could be due to the reforming reaction between CH4 (methanation product) and CO2. Co-impregnation of cobalt with nickel over Sm2O3 had high surface adsorbed oxygen and higher CO selectivity. On the other hand, co-impregnation of ruthenium and nickel over Sm2O3 led to more than one catalytic active site, carbonate species, lack of formate species, and 94% CH4 selectivity. It indicated the following route of CH4 synthe...
Rh‐promoted YZr‐supported Ni catalyst (5Ni/YZr) is investigated for DRM and characterized with X‐... more Rh‐promoted YZr‐supported Ni catalyst (5Ni/YZr) is investigated for DRM and characterized with X‐ray diffraction, Raman, infrared spectroscopy, cyclic reduction–oxidation–reduction temperature programmed experiment, thermogravimetry, and transmission electron microscope. Over 5Ni/YZr, some active sites become inactive under the CO2 stream and limit H2 yield to ∼71%. Upon 4 wt% Rh addition over 5Ni/YZr; more than one type of stable active sites (Rh and Ni) generates, moderate basic sites are enhanced, wide ranges of CO2‐interacted surface species (especially bidentate CO2‐adsorbed species) are grown and graphitic carbon proportion over spent catalyst declines. This resulted in 87.35% H2 yield and 86.73% CO yield up to 420 min. 5Ni4Rh/YZr catalyst maintains ∼80% H2 yield at the end of 27 h of DRM reaction.
A better understanding of the reaction mechanism and kinetics of dry reforming of methane (DRM) r... more A better understanding of the reaction mechanism and kinetics of dry reforming of methane (DRM) remains challenging, necessitating additional research to develop robust catalytic systems with high catalytic performance, low cost, and high stability. Herein, we prepared a zirconia-alumina-supported Ni-Fe catalyst and used it for DRM. Different partial pressures and temperatures are used to test the dry reforming of methane reaction as a detailed kinetic study. The optimal reaction conditions for DRM catalysis are 800°C reaction temperature, 43.42 kPa CO2 partial pressure, and 57.9 kPa CH4 partial pressure. At these optimal reaction conditions, the catalyst shows a 0.436 kPa2 equilibrium constant, a 0.7725 m o l C H 4 /gCat/h rate of CH4 consumption, a 0.00651 m o l C H 4 /m2/h arial rate of CH4 consumption, a 1.6515 m o l H 2 /gCat/h rate of H2 formation, a 1.4386 molCO/gCat/h rate of CO formation. This study’s findings will inspire the cost-effective production of robust catalyti...
Finding a robust catalytic system for hydrogen production via dry reforming of methane (DRM) rema... more Finding a robust catalytic system for hydrogen production via dry reforming of methane (DRM) remains a challenge. Herein, MNi0.9Zr1−xYxO3 (M = Ce, La, and La0.6Ce0.4; x = 0.00, 0.05, 0.07, and 0.09) catalyst was prepared by the sol–gel method, tested for DRM and characterized by surface area and porosity, X‐ray diffraction, H2‐temperature programmed reduction, thermogravimetry, and transmission electron microscopy. In La0.6Ce0.4NiO3 catalyst, the substitution of Ni by 0.1% Zr results in a constant high catalytic activity (83% hydrogen yield at 800°C) due to the presence of reducible “NiO‐species interacted strongly with the support” (stable metallic Ni over reduced catalyst) and redox input by ceria phase for laying instant lattice oxygen during lag‐off period of CO2. Substitution of Ni by Zr and Y in the CeNiO3 catalyst system nurtures Ni3Y (providing highly stable metallic Ni for CH4 decomposition) and cerium yttrium oxide phases (providing strong redox input). CeNi0.9Zr0.01Y0.09O...
Samarium oxide (Sm2O3) is a versatile surface for CO2 and H2 interaction and conversion. Samarium... more Samarium oxide (Sm2O3) is a versatile surface for CO2 and H2 interaction and conversion. Samarium oxide-supported Ni, samarium oxide-supported Co-Ni, and samarium oxide-supported Ru-Ni catalysts were tested for CO2 methanation and were characterized by X-ray diffraction, nitrogen physisorption, infrared spectroscopy, H2-temperature programmed reduction, and X-ray photoelectron spectroscopy. Limited H2 dissociation and widely available surface carbonate and formate species over 20 wt.% Ni, dispersed over Sm2O3, resulted in ~98% CH4 selectivity. The low selectivity for CO could be due to the reforming reaction between CH4 (methanation product) and CO2. Co-impregnation of cobalt with nickel over Sm2O3 had high surface adsorbed oxygen and higher CO selectivity. On the other hand, co-impregnation of ruthenium and nickel over Sm2O3 led to more than one catalytic active site, carbonate species, lack of formate species, and 94% CH4 selectivity. It indicated the following route of CH4 synthe...
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