CO2 Methanation Using Multimodal Ni/SiO2 Catalysts: Effect of Support Modification by MgO, CeO2, and La2O3

Ni/oxide-SiO2 (oxide: MgO, CeO2, La2O3, 10 wt.% target concentration) catalyst samples were prepared by successive impregnation of silica matrix, first with supplementary oxide, and then with Ni (10 wt.% target concentration). The silica matrix with multimodal pore structure was prepared by solvothermal method. The catalyst samples were structurally characterized by N2 adsorption-desorption, XRD, SEM/TEM, and functionally evaluated by temperature programmed reduction (TPR), and temperature programmed desorption of hydrogen (H2-TPD), or carbon dioxide (CO2-TPD). The addition of MgO and La2O3 leads to a better dispersion of Ni on the catalytic surface. Ni/LaSi and Ni/CeSi present a higher proportion of moderate strength basic sites for CO2 activation compared to Ni/Si, while Ni/MgSi lower. CO2 methanation was performed in the temperature range of 150–350 °C and at atmospheric pressure, all silica supported Ni catalysts showing good CO2 conversion and CH4 selectivity. The best catalytic activity was obtained for Ni/LaSi: CO2 conversion of 83% and methane selectivity of 98%, at temperatures as low as 250 °C. The used catalysts preserved the multimodal pore structure with approximately the same pore size for the low and medium mesopores. Except for Ni/CeSi, no particle sintering occurs, and no carbon deposition was observed for any of the tested catalysts.

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Methanation of CO2 Using MIL-53-Based Catalysts: Ni/MIL-53–Al2O3 versus Ni/MIL-53

Catalysts ◽

10.3390/catal11111412 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1412

Author(s):

Oana Grad ◽

Gabriela Blanita ◽

Mihaela D. Lazar ◽

Maria Mihet

Keyword(s):

Prolonged Exposure ◽

Reaction Medium ◽

Catalytic Performance ◽

The Novel ◽

Co2 Conversion ◽

Co2 Methanation ◽

Nanoparticle Deposition ◽

Metallic Particles ◽

Al2o3 Composite ◽

Methane Selectivity

MIL-53 and the MIL-53–Al2O3 composite synthesized by a solvothermal procedure, with water as the only solvent besides CrCl3 and benzene-1,4-dicarboxylic acid (BDC), were used as catalytic supports to obtain the novel MIL-53-based catalysts Ni(10 wt.%)/MIL-53 and Ni(10 wt.%)/MIL-53–Al2O3. Ni nanoparticle deposition by an adapted double-solvent method leads to the uniform distribution of metallic particles, both smaller (≤10 nm) and larger ones (10–30 nm). MIL-53–Al2O3 and Ni/MIL-53–Al2O3 show superior thermal stability to MIL-53 and Ni/MIL-53, while MIL-53–Al2O3 samples combine the features of both MIL-53 and alumina in terms of porosity. The investigation of temperature’s effect on the catalytic performance in the methanation process (CO2:H2 = 1:5.2, GHSV = 4650 h−1) revealed that Ni/MIL-53 is more active at temperatures below 300 °C, and Ni/MIL-53–Al2O3 above 300 °C. Both catalysts show maximum CO2 conversion at 350 °C: 75.5% for Ni/MIL-53 (methane selectivity of 93%) and 88.8% for Ni/MIL-53–Al2O3 (methane selectivity of 98%). Stability tests performed at 280 °C prove that Ni/MIL-53–Al2O3 is a possible candidate for the CO2 methanation process due to its high CO2 conversion and CH4 selectivity, corroborated by the preservation of the structure and crystallinity of MIL-53 after prolonged exposure in the reaction medium.

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Low Temperature Methanation of CO2 on High Ni Content Ni-Ce-ZrOδ Catalysts Prepared via One-Pot Hydrothermal Synthesis

Catalysts ◽

10.3390/catal10010032 ◽

2019 ◽

Vol 10 (1) ◽

pp. 32 ◽

Cited By ~ 2

Author(s):

Vissanu Meeyoo ◽

Noppadol Panchan ◽

Nat Phongprueksathat ◽

Atsadang Traitangwong ◽

Xinpeng Guo ◽

...

Keyword(s):

Hydrothermal Synthesis ◽

Low Temperature ◽

High Surface ◽

Oxygen Species ◽

Co2 Conversion ◽

One Pot ◽

Co2 Methanation ◽

Surface Areas ◽

Ni Content ◽

Methane Selectivity

Ni-Ce-Zr-Oδ catalysts were prepared via one-pot hydrothermal synthesis. It was found that Ni can be partially incorporated into the Ce-Zr lattice, increasing surface oxygen species. The catalysts possess high surface areas even at high Ni loadings. The catalyst with Ni content of 71.5 wt.% is able to activate CO2 methanation even at a low temperature (200 °C). Its CO2 conversion and methane selectivity were reported at 80% and 100%, respectively. The catalyst was stable for 48 h during the course of CO2 methanation at 300 °C. Catalysts with the addition of medium basic sites were found to have better catalytic activity for CO2 methanation.

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Three-Dimensional Mesoporous Ni-CeO2 Catalysts with Ni Embedded in the Pore Walls for CO2 Methanation

Catalysts ◽

10.3390/catal10050523 ◽

2020 ◽

Vol 10 (5) ◽

pp. 523 ◽

Cited By ~ 3

Author(s):

Luhui Wang ◽

Junang Hu ◽

Hui Liu ◽

Qinhong Wei ◽

Dandan Gong ◽

...

Keyword(s):

Three Dimensional ◽

Nitrogen Adsorption ◽

Combustion Method ◽

Catalytic Performance ◽

Oxide Interface ◽

Solution Combustion ◽

Co2 Methanation ◽

Transmission Electron ◽

Temperature Programmed ◽

Adsorption Desorption

Mesoporous Ni-based catalysts with Ni confined in nanochannels are widely used in CO2 methanation. However, when Ni loadings are high, the nanochannels are easily blocked by nickel particles, which reduces the catalytic performance. In this work, three-dimensional mesoporous Ni-CeO2-CSC catalysts with high Ni loadings (20−80 wt %) were prepared using a colloidal solution combustion method, and characterized by nitrogen adsorption–desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM) and H2 temperature programmed reduction (H2-TPR). Among the catalysts with different Ni loadings, the 50% Ni-CeO2-CSC with 50 wt % Ni loading exhibited the best catalytic performance in CO2 methanation. Furthermore, the 50% Ni-CeO2-CSC catalyst was stable for 50 h at 300° and 350 °C in CO2 methanation. The characterization results illustrate that the 50% Ni-CeO2-CSC catalyst has Ni particles smaller than 5 nm embedded in the pore walls, and the Ni particles interact with CeO2. On the contrary, the 50% Ni-CeO2-CP catalyst, prepared using the traditional coprecipitation method, is less active and selective for CO2 methanation due to the larger size of the Ni and CeO2 particles. The special three-dimensional mesoporous embedded structure in the 50% Ni-CeO2-CSC can provide more metal–oxide interface and stabilize small Ni particles in pore walls, which makes the catalyst more active and stable in CO2 methanation.

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CO2 Hydrogenation on NixMg1−xAl2O4: A Comparative Study of MgAl2O4 and NiAl2O4

Catalysts ◽

10.3390/catal11091026 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1026

Author(s):

Boseok Seo ◽

Eunhee Ko ◽

Jinho Boo ◽

Minkyu Kim ◽

Dohyung Kang ◽

...

Keyword(s):

Density Functional ◽

Chemical Properties ◽

Density Functional Theory Calculations ◽

Co2 Hydrogenation ◽

Precipitation Method ◽

Co2 Methanation ◽

Temperature Programmed ◽

Fundamental Insight ◽

Adsorption Desorption ◽

Physical And Chemical

Due to the increasing attention focused on global warming, many studies on reducing CO2 emissions and developing sustainable energy strategies have recently been performed. One of the approaches is CO2 methanation, transforming CO2 into methane. Such transformation (CO2 + 4H2 → CH4 + 2H2O) provides advantages of carbon liquification, storage, etc. In this study, we investigated CO2 methanation on nickel–magnesium–alumina catalysts both experimentally and computationally. We synthesized the catalysts using a precipitation method, and performed X-ray diffraction, temperature-programmed reduction, and N2 adsorption–desorption tests to characterize their physical and chemical properties. NiAl2O4 and MgAl2O4 phases were clearly observed in the catalysts. In addition, we conducted CO2 hydrogenation experiments by varying with temperatures to understand the reaction. Our results showed that CO2 conversion increases with Ni concentration and that MgAl2O4 exhibits high selectivity for CO. Density functional theory calculations explained the origin of this selectivity. Simulations predicted that adsorbed CO on MgAl2O4(100) weakly binds to the surface and prefers to desorb from the surface than undergoing further hydrogenation. Electronic structure analysis showed that the absence of a d orbital in MgAl2O4(100) is responsible for the weak binding of CO to MgAl2O4. We believe that this finding regarding the origin of the CO selectivity of MgAl2O4 provides fundamental insight for the design methanation catalysts.

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Effect of Support and Chelating Ligand on the Synthesis of Ni Catalysts with High Activity and Stability for CO2 Methanation

Catalysts ◽

10.3390/catal10050493 ◽

2020 ◽

Vol 10 (5) ◽

pp. 493 ◽

Cited By ~ 3

Author(s):

Vetrivel Shanmugam ◽

Stefan Neuberg ◽

Ralf Zapf ◽

Helmut Pennemann ◽

Gunther Kolb

Keyword(s):

Catalytic Performance ◽

Impregnation Method ◽

Chelating Ligands ◽

Co2 Conversion ◽

Ni Catalysts ◽

Co2 Methanation ◽

High Co2 ◽

X Ray ◽

Metal Support Interaction ◽

Methane Selectivity

Carbon dioxide methanation was carried out over Ni-based catalysts on different supports and chelating ligands in microreactors. To investigate the influence of chelating ligands and supports, the Ni catalysts were prepared using different support such as CeO2, Al2O3, SiO2, and SBA-15 by a citric acid (CA)-assisted impregnation method. The properties of the developed catalysts were studied by X-ray diffraction (XRD), Transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) measurement, and the results show that the addition of CA in the impregnation solution improved the dispersion, refines the particle size, and enhanced the interaction of nickel species. The catalytic performance of the developed Ni catalysts were evaluated by CO2 methanation in microreactors in the temperature range of 275 °C–375 °C under 12.5 bar pressure. All the catalysts exhibit high CO2 conversion and extremely high selectivity to methane. However, the catalysts prepared via CA-assisted method exhibited excellent activity and stability, compared with Ni catalysts prepared by a conventional impregnation method, which could be attributed to highly dispersed nickel particles with strong metal–support interaction. The activity of CO2 methanation followed the order of Ni/CeO2-CA > Ni/SBA-15-CA > Ni/Al2O3-CA > Ni/SiO2-CA > Ni/CeO2. The Ni/CeO2 catalysts have also been prepared using different chelating ligands such as ethylene glycol (EG), sucrose (S), oxalic acid (OA) and ethylene diamine tetra acidic acid (EDTA). Among the tested catalysts prepared with different support and chelating ligands, the Ni/CeO2 catalyst prepared via CA-assisted method gave superior catalytic performance and it could attain 98.6% of CO2 conversion and 99.7% methane selectivity at 325 °C. The partial reduction of the CeO2 support generates more surface oxygen vacancies and results in a high CO2 conversion and methane selectivity compared with other catalysts. The addition of CA as promoter favored the synergistic effect of Ni and support, which led to high dispersion, controls the size, and stabilizes the Ni nanoparticles. Furthermore, the Ni/CeO2-CA catalyst yields high CO2 conversion in a time-on-stream study due to the ability of preventing the carbon deposition and sintering of Ni particles under the applied reaction conditions. However, the Ni/Al2O3-CA and Ni/SBA-15-CA catalysts showed stable performance for 100 h of time on stream.

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Insight into Active Centers and Anti-Coke Behavior of Niobium-Containing SBA-15 for Glycerol Dehydration

Catalysts ◽

10.3390/catal11040488 ◽

2021 ◽

Vol 11 (4) ◽

pp. 488

Author(s):

Katarzyna Stawicka ◽

Maciej Trejda ◽

Maria Ziolek

Keyword(s):

Coke Formation ◽

Catalytic Performance ◽

Acid Sites ◽

Silica Matrix ◽

High Concentration ◽

Active Centers ◽

Acidic Sites ◽

Glycerol Dehydration ◽

Adsorption Desorption ◽

Insight Into

Niobium containing SBA-15 was prepared by two methods: impregnation with different amounts of ammonium niobate(V) oxalate (Nb-15/SBA-15 and Nb-25/SBA-15 containing 15 wt.% and 25 wt.% of Nb, respectively) and mixing of mesoporous silica with Nb2O5 followed by heating at 500 °C (Nb2O5/SBA-15). The use of these two procedures allowed obtaining materials with different textural/surface properties determined by N2 adsorption/desorption isotherms, XRD, UV-Vis, pyridine, and NO adsorption combined with FTIR spectroscopy. Nb2O5/SBA-15 contained exclusively crystalline Nb2O5 on the SBA-15 surface, whereas the materials prepared by impregnation had both metal oxide and niobium incorporated into the silica matrix. The niobium species localized in silica framework generated Brønsted (BAS) and Lewis (LAS) acid sites. The inclusion of niobium into SBA-15 skeleton was crucial for the achievement of high catalytic performance. The strongest BAS were on Nb-25/SBA-15, whereas the highest concentration of BAS and LAS was on Nb-15/SBA-15 surface. Nb2O5/SBA-15 material possessed only weak LAS and BAS. The presence of the strongest BAS (Nb-25/SBA-15) resulted in the highest dehydration activity, whereas a high concentration of BAS was unfavorable. Silylation of niobium catalysts prepared by impregnation reduced the number of acidic sites and significantly increased acrolein yield and selectivity (from ca. 43% selectivity for Nb-25/SBA-15 to ca. 61% for silylated sample). This was accompanied by a considerable decrease in coke formation (from 47% selectivity for Nb-25/SBA-15 to 27% for silylated material).

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Insights into the Development of Cu-based Photocathodes for Carbon Dioxide (CO2) Conversion

Green Chemistry ◽

10.1039/d0gc04417b ◽

2021 ◽

Author(s):

Wenzhang Li ◽

Keke Wang ◽

yanfang Ma ◽

Yang Liu ◽

Weixin Qiu ◽

...

Keyword(s):

Carbon Dioxide ◽

Fossil Fuels ◽

Environmental Issues ◽

Energy Crisis ◽

Co2 Conversion ◽

Carbon Dioxide Co2 ◽

Reduction Of Co2

The ever-growing factitious over-consumption of fossil fuels and the accompanying massive emissions of CO2 have caused severe energy crisis and environmental issues. Photoelectrochemical (PEC) reduction of CO2 that can combine...

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Hydrogen Adsorption Capacity Investigation of Ni-Co-Al Mixed Oxides

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.917.360 ◽

2014 ◽

Vol 917 ◽

pp. 360-364 ◽

Cited By ~ 4

Author(s):

M. Abdus Salam ◽

Suriati Sufian

Keyword(s):

Hydrogen Adsorption ◽

Mixed Oxides ◽

Textural Properties ◽

Metal Dispersion ◽

Temperature Programmed Reduction ◽

Oxide Formation ◽

Nickel Cobalt ◽

Icp Ms ◽

Temperature Programmed ◽

Adsorption Desorption

Micro-mesoporous mixed oxides containing nickel, cobalt and aluminum have been synthesized using conventional coprecipitation method. FESEM and HRTEM analyses demonstrated the flower and hexagonal plate-like nanostructured of mixed oxides. Different mixed oxide formation, homogenous metal dispersion, textural properties were investigated using XRD, ICP-MS and BET (N2 adsorption-desorption) techniques. nanostructured mixed oxides exhibited 2.6 wt% hydrogen adsorption that were studied using temperature programmed reduction-adsorption-desorption (H2-TPR/TPD) and thermogravimetric and differential thermal analysis (TGA-DTA) techniques. Investigation corresponds that morphologies, textural properties and surface energy of mixed oxides are important in hydrogen adsorption.

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Structural and surface aspects of thermally treated copper aluminium mixed hydroxides

Canadian Journal of Chemistry ◽

10.1139/v91-223 ◽

1991 ◽

Vol 69 (10) ◽

pp. 1511-1515 ◽

Cited By ~ 5

Author(s):

Awad I. Ahmed ◽

S. E. Samra ◽

S. A. El-Hakam

Keyword(s):

Pore Structure ◽

Copper Content ◽

Textural Properties ◽

Nitrogen Adsorption ◽

Phase Changes ◽

X Ray Diffraction ◽

X Ray ◽

Surface Areas ◽

Structure Surface ◽

Adsorption Desorption

CuO–Al2O3 catalysts containing various amounts of copper oxide have been prepared by precipitation. The phase changes were studied by X-ray diffraction. The results obtained revealed that the thermal treatment of solid CuO–Al2O3 at 700 °C produced only crystalline CuO. Heating to 900 °C led to the formation of copper alumina spinel together with unreacted CuO and γ-Al2O3. The spinel content was found to increase with increasing copper content. Nitrogen adsorption–desorption isotherms on the calcined samples have been measured. Surface areas have been calculated and the pore structure analysed. The textural properties of the system were found to depend on both the copper content and the calcination temperature. Key words: CuO, Al2O3 catalysts, structure, surface area, pore structure.

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