Template-Assisted Wet-Combustion Synthesis of Fibrous Nickel-Based Catalyst for Carbon Dioxide Methanation and Methane Steam Reforming

Abstract

Efficient capture and recycling of CO enable not only prevention of global warming but also the supply of useful low-carbon fuels. The catalytic conversion of CO into an organic compound is a promising recycling approach which opens new concepts and opportunities for catalytic and industrial development. Here we report about template-assisted wet-combustion synthesis of a one-dimensional nickel-based catalyst for carbon dioxide methanation and methane steam reforming. Because of a high temperature achieved in a short time during reaction and a large amount of evolved gases, the wet-combustion synthesis yields homogeneously precipitated nanoparticles of NiO with average particle size of 4 nm on alumina nanofibers covered with a NiAlO nanolayer. The as-synthesized core-shell structured fibers exhibit outstanding activity in steam reforming of methane and sufficient activity in carbon dioxide methanation with 100% selectivity toward methane formation. The as-synthesized catalyst shows stable operation under the reaction conditions for at least 50 h.

In Situ Growth of NiFe Alloy Nanoparticles Embedded into N-Doped Bamboo-like Carbon Nanotubes as a Bifunctional Electrocatalyst for Zn–Air Batteries

“…As observed in Figure c, the high-resolution C 1s spectrum can be deconvoluted into two components corresponding to the carbon species in different functional bonds: C–C (∼284.8 eV) and C–N (∼286.0 eV). , The XPS N 1s spectrum of NiFe@NBCNT is deconvoluted into two peaks centered at ∼398.8 and ∼401.1 eV, corresponding to the pyridinic-N and graphitic-N species, respectively (Figure d). , It is generally accepted that the graphitic-N moiety acts as the vital role in the ORR process and that pyridinic-N structures are responsible for the formation of C–N sites. , As shown in Figure e, the Ni 2p spectrum presents two main structures, resulting from the spin–orbit splitting of the p orbital whose main peaks at ∼854.1 and ∼871.9 eV, together with two satellite peaks at ∼862.1 and ∼880.3 eV, correspond to the Ni 2+ 2p 3/2 and Ni 2p 1/2 , respectively. In the Fe 2p spectrum, the peaks of Fe 2p 3/2 at ∼711.6 eV and Fe 2p 1/2 at ∼725.3 eV are combined with the satellite peaks at ∼707.1 and ∼720.6 eV, which can be ascribed to the formation of Fe­(OH) 2 or FeOOH, which are also consistent with many previous reports. − Indeed, the XRD pattern confirmed that the NiFe alloy is still a major phase in NiFe@NBCNT hybrids. The presence of Ni 2+ and the Fe 3+ /Fe 2+ species in the catalyst may be ascribed to the reason that the surface of the NiFe alloy is easily oxidized to its oxide or hydroxide, which makes the metallic Ni or Fe located inside the sample not enough to be detected by XPS.…”

A Short Review on Ni Based Catalysts and Related Engineering Issues for Methane Steam Reforming

“…The catalysts that were calcined at 750 • C showed the highest methane conversion in all cases. The catalysts that were calcined at 900 • C were tested with a water/methane ratio 1 at 600, 700, and 900 • C showing higher deactivation with respect to ones calcined at 600 • C. Aghayan et al reported the preparation of a one-dimensional nickel-based catalysts, by template assisted wet-combustion synthesis, for methane steam reforming and methanation reactions [25]. The catalysts were prepared by the infiltration of nickel nitrate and glycine solution in the blocks of nanofibers of mesoporous self-oriented γ-alumina, and subsequent calcined at 400 • C for 30 min.…”

Barium promoted Ni/Sm2O3 catalysts for enhanced CO2 methanation

“…H 2 -TPR analysis of 5Ni–5Ba/Sm 2 O 3 showed the catalyst was fully reduced at temperature below 500 °C, thus high temperature reduction may cause particle sintering. 38 Nevertheless, all the catalysts showed 100% selectivity towards CH 4 . The results obtained on the effect of reduction temperature is highly important to show the role of Ba in improving the activity of Ni catalysts particularly for CO 2 methanation at low temperature.…”