Effect of Calcination Temperature on Cu-Modified Ni Catalysts Supported on Mesocellular Silica for Methane Decomposition

Abstract

Catalytic methane decomposition has been considered suitable for the green and sustainable production of high-purity H 2 to help reduce greenhouse gas emissions. This research developed a copper-modified nickel-supported mesocellular silica NiCu/MS( x ) catalyst synthesized at different calcination temperatures to improve the activity and stability in the CH 4 decomposition reaction at 600 °C. Ni and Cu metals were loaded on a mesocellular silica (MS) support using a co-impregnation method and calcined at different temperatures (500, 600, 700, and 800 °C). The NiCu/MS(600) catalyst not only had the highest H 2 yield (32.78%), which was 1.47–3.87 times higher than those of the other NiCu/MS( x ) catalysts, but also showed better stability during the reaction. Calcination at 600 °C helps improve the active nickel dispersion, the reducibility of the NiCu catalyst, and the interaction of the NiCu–MS support, leading to the formation of fishbone and platelet carbon nanofibers via a tip-growth mechanism, resulting in the NiCu metals remaining active during the reaction.

Highly Efficient Conversion of Greenhouse Gases Using a Quadruple Mixed Oxide-Supported Nickel Catalyst in Reforming Process

“…The Ni 2p 3/2 binding energy peak of the used catalyst could be deconvoluted into three peaks of 853.2, 857.2, and 863.3 which were assigned to the metallic nickel, Ni 2+ state, and the satellite peaks of complex nickel, respectively. , The oxide quad-blend Ce–Mg–Zn–Al support could help stabilize the active metallic nickel, especially with the composition of Ce–Mg-0.5Zn–Al-supported nickel catalyst having the highest metallic nickel intensity, resulting in the Ni/CeMg0.5ZnAl catalyst showing the highest conversion, as well as better catalyst stability during the reaction. The C 1s spectra, accounting for the spin–orbit coupling, can be represented by five distinct peaks at 284.2, 285.0, 285.7, 286.4, and 287.6 eV, which correspond to the carbide phase, sp 2 -carbon (CC), sp 3 -carbon (C–C), C–O, and CO functional groups, respectively . The concentration of sp 2 -carbon and sp 3 -carbon hybridization and the relative sp 2 /sp 3 intensity ratio are evaluated from the XPS measurements, as shown in Table S2.…”

“…The Ni 2p 3/2 binding energy peak of the used catalyst could be deconvoluted into three peaks of 853.2, 857.2, and 863.3 which were assigned to the metallic nickel, Ni 2+ state, and the satellite peaks of complex nickel, respectively. 6,27 The oxide quad-blend Ce−Mg−Zn−Al support could help stabilize the 50 The concentration of sp 2 -carbon and sp 3 -carbon hybridization and the relative sp 2 /sp 3 intensity ratio are evaluated from the XPS measurements, as shown in Table S2. The structure of coke deposited on the catalyst surface consisted of sp 2 -and sp 3 -hybridization: a higher amount of coke deposition contained a higher carbon structure of sp 2hybridization.…”

Ni-Based Bimetallic Catalysts for Hydrogen Production Via (Sorption-Enhanced) Steam Methane Reforming

“…The presence of nickel oxide and hydroxide species in the samples is due to the passivation layers formed on the surface of the fine Ni particles at room temperature [35,36]. In the Cu 2p spectrum, the peaks at 934.4 and 954 eV correspond to CuO (Cu 2+ ) 2p 3/2 and Cu 0 2p ½, respectively [37,38]. The Fe 2p spectrum contains three main peaks with relatively low intensity at 707, 711.5, and 724.8 eV, which correspond to Fe 0 2p 3/ 2, a combination of Fe 2+ 2p 3/2 and Fe 3+ 2p 3/2, and a combination of Fe 2+ 2p 1/2 and Fe 3+ 2p 1/2 [39,40].…”

Hydrogen Production via Methane Decomposition over Alumina Doped with Titanium Oxide‐Supported Iron Catalyst for Various Calcination Temperatures

“…Increasing calcination temperature increases particle size, pore diameter, and crystal size while decreasing pore volume and specific surface area. The CH 4 conversion is favored by increasing the calcination temperature up to a certain point, but after that point, it causes a reduction in its catalytic activity, mainly caused by the agglomeration of the particles and reduction in the specific surface area [40] . At higher calcination temperatures, particle agglomeration occurs, resulting in larger crystal sizes and a reduction in specific surface area due to the collapse of the porous structure [41] .…”

“…The CH 4 conversion is favored by increasing the calcination temperature up to a certain point, but after that point, it causes a reduction in its catalytic activity, mainly caused by the agglomeration of the particles and reduction in the specific surface area. [40] At higher calcination temperatures, particle agglomeration occurs, resulting in larger crystal sizes and a reduction in specific surface area due to the collapse of the porous structure. [41] For example, Al‐Fatesh and his colleagues [41] examined iron catalysts supported on alumina prepared with three different methods and used two calcination temperatures.…”