Effective suppression of deactivation by utilizing Ni-doped ordered mesoporous alumina-supported catalysts for the production of hydrogen and CO gas mixture from methane

Kim, Daegak; Jeon, Jonghyun; Lee, Won Suk; Lee, Jinwon; Ha, Kyoung-Su

doi:10.1016/j.ijhydene.2017.08.044

Cited by 9 publications

(4 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The result of SAXS of the χ-Fe 5 C 2 @SiO 2 _H catalyst in Figure 4 c shows a slightly broadened peak at approximately 0.13 Å −1 , and the pore structure could be considered similar to that of MCM-41 since the peak appears very similar to the reflection of the (100) plane of MCM-41 in terms of q vector and profile. The pores of the silica shell appeared to have a wormhole-like and short-range morphology, as shown in TEM images, and it could be corroborated by SAXS results that the pore structure seemed to be a partially ordered mesoporous structure; similar structures can be found in literature elsewhere [ 19 , 22 , 23 , 24 ]. The wall thickness of the pore structure was calculated using the d-spacing of the (100) plane and pore size from the N 2 -physisorption result.…”

Section: Resultssupporting

confidence: 84%

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Cha

Kim²,

Choi³

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

Among various iron carbide phases, χ-Fe5C2, a highly active phase in Fischer–Tropsch synthesis, was directly synthesized using a wet-chemical route, which makes a pre-activation step unnecessary. In addition, χ-Fe5C2 nanoparticles were encapsulated with mesoporous silica for protection from deactivation. Further structural analysis showed that the protective silica shell had a partially ordered mesoporous structure with a short range. According to the XRD result, the sintering of χ-Fe5C2 crystals did not seem to be significant, which was believed to be the beneficial effect of the protective shell providing restrictive geometrical space for nanoparticles. More interestingly, the protective silica shell was also found to be effective in maintaining the phase of χ-Fe5C2 against re-oxidation and transformation to other iron carbide phases. Fischer–Tropsch activity of χ-Fe5C2 in this study was comparable to or higher than those from previous reports. In addition, CO2 selectivity was found to be very low after stabilization.

show abstract

Section: Resultssupporting

confidence: 84%

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Cha

Kim²,

Choi³

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

show abstract

“…Therefore, considerable effort has been devoted to exploring and optimizing their properties. [33][34][35][36] Perhaps most important is the fact that it is relatively difficult to obtain high surface area spinel-based active catalysts due to the fact that high temperature processing is required simply to produce the spinel structure. Such high temperature processing frequently equates to extensive loss of surface area.…”

Section: Introductionmentioning

confidence: 99%

“…Alumina supported nickel catalysts are relatively inexpensive compared to other types of catalysts. Therefore, considerable effort has been devoted to exploring and optimizing their properties . Perhaps most important is the fact that it is relatively difficult to obtain high surface area spinel‐based active catalysts due to the fact that high temperature processing is required simply to produce the spinel structure.…”

Section: Introductionmentioning

confidence: 99%

Chemical modification in and on single phase [NiO]_0.5[Al₂O₃]_0.5 nanopowders produces “chocolate chip‐like” Ni_x@[NiO]_0.5‐x[Al₂O₃]_0.5 nanocomposite nanopowders

Wang

Sun

et al. 2019

J Am Ceram Soc

View full text Add to dashboard Cite

Phase‐pure [NiO]0.5[Al2O3]0.5 spinel nanoparticles (NPs) with limited aggregation were obtained via liquid‐feed flame spray pyrolysis (LF‐FSP) by combusting metalloorganic precursor solutions. Thereafter “chocolate chip‐like” Nix[NiO0.5‐x][Al2O3]0.5 nanoparticles consisting of primary [NiO0.5‐x][Al2O3]0.5 particles with average particle sizes of 40‐60 nm decorated with Ni metal particles (<10 nm in diameter) dispersed on the surface were synthesized by heat treating the spinel NPs at 800°C/7 h in flowing 5% H2:N2 100 mL/min in a fluidized bed reactor. The synthesized materials were characterized using TEM, XRD, FTIR, and TGA/DTA. The Ni depleted areas consist primarily of γ‐Al2O3. The Ni content (800°C) was determined by TGA to be ≈11.3 wt.% based on TGA oxidation behavior. The successful synthesis of such nanocomposites with limited aggregation on a high temperature support provides a facile route to synthesize well‐defined NP catalysts. This work serves as a baseline study for an accompanying paper, wherein thin, flexible, dense films made from these same NPs are used as regenerable catalysts for carbon nanotube syntheses.

show abstract

“…This combined methane reforming route is known as autothermal methane reforming [13][14][15]. SRM and ATR, although they give a good H 2 /CO ratio, requires special precautions and they are at the stage of laboratory testing [16][17][18]. Carbon dioxide conversion of methane, also called "dry" reforming of methane, is of particular interest, since it allows for utilization at one time two greenhouse gases -methane and carbon dioxide.…”

Section: Introductionmentioning

confidence: 99%

Dry Reforming of Methane on Carriers and Oxide Catalysts to Synthesis-Gas

Dossumov

Yergaziyeva

Myltykbayeva

et al. 2018

Eurasian Chem. Tech. J.

View full text Add to dashboard Cite

The catalytic activity of carriers: θ‒Al2O3, γ‒Al2O3, 5A, 4A, 3A and 13X and the oxides of metals of variable valency ‒ NiO, La2O3, CuO, MoO3, MgO, V2O5, WO3, CoO, Cr2O3, ZnO, ZrO2, CeO2, Fe2O3, supported on the effective carrier γ‒Al2O3 by the method of capillary impregnation of the support with solutions of nitric salts of metals were investigated in the process of carbon dioxide conversion of methane (DRM). The optimal technological regimes for the process were: the reaction temperature -800 °C, the space velocity of the initial reactants ‒ 1500 h-1 with a methane to carbon dioxide ratio equal to 1. It was found that among the studied catalysts the highest activity is shown by the NiO/γ‒Al2O3 catalyst, where the yields of hydrogen and carbon monoxide reaches 45.4 and 42.4% by volume, respectively, when methane conversion is 89%. The XRF method showed that the content of alumina and nickel oxide after the reaction remained unchanged at 96.7 and 3.0%, respectively. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), small angle X-ray scattering (XRS) determined that nickel-containing NiO/γ‒Al2O3 catalyst form nickel nanoparticles (6.4‒10 and 50‒150 nm) and a uniform their distribution on the surface of the carrier takes place. These physical chemical characteristics have a positive effect on the activity of NiO/γ‒Al2O3 catalyst in the process of carbon dioxide conversion of methane to synthesis gas.

show abstract

Effective suppression of deactivation by utilizing Ni-doped ordered mesoporous alumina-supported catalysts for the production of hydrogen and CO gas mixture from methane

Cited by 9 publications

References 55 publications

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Chemical modification in and on single phase [NiO]_0.5[Al₂O₃]_0.5 nanopowders produces “chocolate chip‐like” Ni_x@[NiO]_0.5‐x[Al₂O₃]_0.5 nanocomposite nanopowders

Dry Reforming of Methane on Carriers and Oxide Catalysts to Synthesis-Gas

Contact Info

Product

Resources

About

Effective suppression of deactivation by utilizing Ni-doped ordered mesoporous alumina-supported catalysts for the production of hydrogen and CO gas mixture from methane

Cited by 9 publications

References 55 publications

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer–Tropsch Synthesis

Chemical modification in and on single phase [NiO]0.5[Al2O3]0.5 nanopowders produces “chocolate chip‐like” Nix@[NiO]0.5‐x[Al2O3]0.5 nanocomposite nanopowders

Dry Reforming of Methane on Carriers and Oxide Catalysts to Synthesis-Gas

Contact Info

Product

Resources

About

Chemical modification in and on single phase [NiO]_0.5[Al₂O₃]_0.5 nanopowders produces “chocolate chip‐like” Ni_x@[NiO]_0.5‐x[Al₂O₃]_0.5 nanocomposite nanopowders