Steam CO2 Reforming Of Methane Research Articles

Studies on the steam CO2 reforming of methane over ordered mesoporous nickel–magnesium–alumina catalysts

Ordered mesoporous materials have received much attention because of their high surface area and ordered pore structure. The Mg-promoted ordered mesoporous nickel–alumina catalysts (M-Mg x NA), which were prepared using the evaporation induced self-assembly method, were investigated in the Steam CO2 Reforming (SCR) of methane. The fresh and spent catalysts were characterized by various analytical techniques such as N2 physisorption, small-angle X-ray scattering, X-ray diffraction, temperature-programmed reduction, thermogravimetric analysis, transmission electron microscopy and CO2-temperature programmed desorption analysis. We have found that the M-Mg x NA catalyst has a larger surface area and a narrower pore size distribution than the Ni/Al2O3 catalyst (NA); furthermore, the M-Mg x NA catalyst exhibits high catalytic stability under the tested conditions of 600 °C, 1 bar and feed molar ratio of CH4:CO2:H2O = 1:1:1. We consider that the ordered mesoporosity prevents the nickel particles from sintering because of the confinement effect and decreases the particle size in the SCR reaction. Thus, the Mg-promoted ordered mesoporous nickel-alumina catalyst shows enhanced resistance to carbon formation during the steam CO2 reforming of methane.

Modified Nano-Perovskite Catalysts for the Steam and CO2 Reforming of Methane.

This paper describes the synthesis and characterization of La0.8Sr0.2NiO3 nano-perovskite type catalyst for steam-CO2 reforming (SCR) and CO2 reforming (DR) of methane. Effect of gelation agents such as PVA, EDTA and PAA on nano-perovskite structures was investigated. XRD, H2-TPR and FT-IR analysis were used to characterize the prepared catalysts. The catalytic reaction was performed in a fixed bed reactor system at 1 atm and 800 °C. The feed ratio of CH4:H2O:CO2 as reactants was adjusted according to the SCR and DR reactions. As a result, CH4 and CO2 conversions of PVA agent catalyst were higher than that of PAA and EDTA agent catalyst for DR reaction because the PVA agent catalyst had a well-established perovskite, a high absorption, a high reducibility. However, the PAA agent catalyst had a higher reactivity due to its high interaction of catalysts for SCR of methane due to its strong interaction of catalysts.

Steam CO2 reforming of methane over La1−xCexNiO3 perovskite catalysts

Steam CO2 reforming of methane was carried out over cerium substituted perovskite catalysts. Among the catalysts studied, La0.9Ce0.1NiO3 showed the best performance with 49% of methane and 14% of CO2 conversion under the tested conditions. The chemical and structural properties of the catalysts before and after the reaction were studied by N2 physisorption, X-ray diffraction, CO2-TPD, TPH, TPR, TGA and TEM. It was found that most of Ce existed as CeO2 rather than being incorporated in perovskite lattice because of large difference in ionic radii between La3+ and Ce4+. Few substitution of Ce in A site resulted in high degree of reduction for active Ni species with good catalytic activity which was further decreased with increasing Ce concentration; substitution of large amount of Ce species led to methanation of CO2 and formation of large nickel cluster. TPH and TGA analysis revealed that Ce substituted catalyst has better resistance to coke deposition compared to non-promoted perovskite catalyst.

Preparation and Characterization of Ni-Based Perovskite Catalyst for Steam CO2 Reforming of Methane

Steam CO2 reforming of methane was investigated over Ni-based perovskite catalyst to produce desired H2/CO ratio by adjusting the feed ratio of CH4, CO2 and H2O for floating GTL process application. La modified perovskites were prepared by the Pechini method and calcined in air and the Ni-based catalysts were prepared by dispersing Ni on the La modified perovskite by an incipient wetness impregnation. The catalysts before and after the reaction were characterized by N2 physisoprtion, CO chemisoprtion, XRD, TPR and SEM techniques. To control desired H2/CO ratio, simulation for SCR was carried out by Aspen plus, and product distribution for SCR was investigated in a fixed bed reactor system using feed ratio estimated by simulation. The Ni-based perovskite catalysts were found to give CH4 and CO2 conversions of up to 82% and 60% respectively to yield a H2/CO product ratio close to 2.

Steam-CO2 reforming of methane on Ni/γ-Al2O3-deposited metallic foam catalyst for GTL-FPSO process

The steam-CO2 reforming (SCR) of methane on a Ni/γ-Al2O3-deposited metallic foam catalyst was assessed for the GTL-FPSO (gas to liquids-floating production, storage and offloading) process. The metallic foam catalyst was prepared by the wash-coating of a γ-Al2O3 layer and the subsequent impregnation of a Ni catalyst. The prepared Ni/γ-Al2O3/Ni foam catalyst was characterized by scanning electron microscopy and X-ray diffraction. The SCR reaction on the Ni/γ-Al2O3/Ni foam catalyst was evaluated at different temperatures and space velocities. A uniform and robust catalyst layer was formed on the surface of the Ni foam. The metallic foam catalyst showed a higher CH4 conversion than a pellet catalyst. The durability of the metallic foam catalyst was evaluated at a space velocity of 130,000h−1 for 50h. The CH4 conversion decreased by 10% compared to that after the reaction was initiated.