Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Co-Precipitated Ni-Mg-Al Hydrotalcite-Derived Catalyst Promoted with Vanadium for CO2 Methanation.

ABSTRACT: Co-precipitated Ni-Mg-Al hydrotalcite-derived catalyst promoted with vanadium were synthesized with different V loadings (0-4 wt%) and studied in CO2 methanation. The promotion with V significantly changes textural properties (specific surface area and mesoporosity) and improves the dispersion of nickel. Moreover, the vanadium promotion strongly influences the surface basicity by increasing the total number of basic sites. An optimal loading of 2 wt% leads to the highest activity in CO2 methanation, which is directly correlated with specific surface area, as well as the basic properties of the studied catalysts.

SUBMITTER: Summa P

PROVIDER: S-EPMC8588090 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Co-Precipitated Ni-Mg-Al Hydrotalcite-Derived Catalyst Promoted with Vanadium for CO2 Methanation.

Summa Paulina P Świrk Katarzyna K Wierzbicki Dominik D Motak Monika M Alxneit Ivo I Rønning Magnus M Da Costa Patrick P

Molecules (Basel, Switzerland) 20211028 21

Co-precipitated Ni-Mg-Al hydrotalcite-derived catalyst promoted with vanadium were synthesized with different V loadings (0-4 wt%) and studied in CO2 methanation. The promotion with V significantly changes textural properties (specific surface area and mesoporosity) and improves the dispersion of nickel. Moreover, the vanadium promotion strongly influences the surface basicity by increasing the total number of basic sites. An optimal loading of 2 wt% leads to the highest activity in C ...[more]

PMID: 34770915

Similar Datasets

Ni-Mg-Al Hydrotalcite-Derived Catalysts for Ammonia Decomposition-From Precursor to Effective Catalyst.

Project description:A series of Ni-Mg-Al hydrotalcite-derived mixed metal oxides with different Ni/Mg ratios were prepared by the coprecipitation method followed by calcination at 600 °C. The hydrotalcite-like materials, as well as their calcined forms, were characterized with respect to structure (XRD, UV-Vis DRS), chemical composition (ICP-OES), textural parameters (low-temperature N2 sorption), dispersion of nickel species (H2-chemisorption) and nickel species reducibility (H2-TPR). Moreover, the process of hydrotalcite-like materials' thermal transformation to mixed metal oxide systems in air and argon flow was studied by the TG-DTA method. The activity of the studied catalysts in the reaction of ammonia decomposition increased with an increase in nickel content in the samples. It was shown that nickel species incorporated into the Mg-Al oxide matrix segregated under conditions of reduction in a flow of H2/Ar mixture with the formation of metallic nickel crystallites of the average size of about 10 nm. The size of nickel crystallites was practically no change in the subsequent reduction cycles and resulted in increased catalytic activity in comparison to larger crystallites of metallic nickel (20.2-23.6 nm) deposited on Al2O3 and MgO.

| S-EPMC11901857 | biostudies-literature

Plasma-assisted CO2 methanation: effects on the low-temperature activity of an Ni-Ce catalyst and reaction performance.

Project description:Ni-Ce three-dimensional material with macropore diameter of 146.6 ± 8.4 nm was synthesized and used as a methanation catalyst. Firstly, H2 reduction of the catalyst was conducted in the thermal fixed bed and plasma reactor, respectively, then X-ray diffraction (XRD) and CO2 temperature programmed desorption experiments on the two reduced samples were carried out to reveal the plasma effect on the catalyst's physico-chemical properties. It was found that plasma reduction created more abundant basic sites for CO2 adsorption, in particular the medium basic sites were even doubled compared with the thermal-reduced catalysts. The plasma-reduced catalyst exhibited excellent low-temperature activity, ca 50-60°C lower than the thermal catalyst (the maximum CO2 conversion point). Based on the optimum reduced catalyst, plasma effect in the reactor level was further investigated under high gas hour space velocity of approximately 50 000 h-1. The plasma reactor showed higher CO2 conversion capacity and efficiency than the thermal reactor.

| S-EPMC6837228 | biostudies-literature

CO2 Methanation: Nickel-Alumina Catalyst Prepared by Solid-State Combustion.

Project description:The development of solvent-free methods for the synthesis of catalysts is one of the main tasks of green chemistry. A nickel-alumina catalyst for CO2 methanation was synthesized by solid-state combustion method using hexakis-(imidazole) nickel (II) nitrate complex. Using X-ray Powder Diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Hydrogen temperature-programmed reduction (H2-TPR), it was shown that the synthesized catalyst is characterized by the localization of easily reduced nickel oxide on alumina surface. This provided low-temperature activation of the catalyst in the reaction mixture containing 4 vol% CO2. In addition, the synthesized catalyst had higher activity in low-temperature CO2 methanation compared to industrial NIAP-07-01 catalyst, which contained almost three times more hard-to-reduce nickel-aluminum spinel. Thus, the proposed approaches to the synthesis and activation of the catalyst make it possible to simplify the catalyst preparation procedure and to abandon the use of solvents, which must be disposed of later on.

| S-EPMC8623454 | biostudies-literature

Highly Active Ce- and Mg-Promoted Ni Catalysts Supported on Cellulose-Derived Carbon for Low-Temperature CO2 Methanation.

Project description:The CO2 methanation performance of Mg- and/or Ce-promoted Ni catalysts supported on cellulose-derived carbon (CDC) was investigated. The samples, prepared by biomorphic mineralization techniques, exhibit pore distributions correlated to the particle sizes, revealing a direct effect of the metal content in the textural properties of the samples. The catalytic performance, evaluated as CO2 conversion and CH4 selectivity, reveals that Ce is a better promoter than Mg, reaching higher conversion values in all of the studied temperature range (150-500 °C). In the interval of 350-400 °C, Ni-Mg-Ce/CDC attains the maximum yield to methane, 80%, reaching near 100% CH4 selectivity. Ce-promoted catalysts were highly active at low temperatures (175 °C), achieving 54% CO2 conversion with near 100% CH4 selectivity. Furthermore, the large potential stability of the Ni-Mg-Ce/CDC catalyst during consecutive cycles of reaction opens a promising route for the optimization of the Sabatier process using this type of catalyst.

| S-EPMC9161724 | biostudies-literature

Photo- and Thermocatalytic CO2 Methanation: A Comparison of Ni/Al2O3 and Ni-Ce Hydrotalcite-Derived Materials under UV and Visible Light.

Project description:Catalysts derived from Ni/Al/Mg/Ce hydrotalcite were prepared via a co-precipitation method, varying the Ce/Al atomic ratio. All of the catalytic systems thus prepared were tested for CO2 methanation under dark and photocatalytic conditions (visible and ultraviolet) under continuous flow with the light intensity set to 2.4 W cm-2. The substitution of Al by Ce formed a solid solution, generating oxygen vacancies and Ce3+/Ce4+ ions that helped shift the dissociation of CO2 towards the production of CH4, thus enhancing the activity of methanation, especially at lower temperatures (<523 K) and with visible light at temperatures where other catalysts were inactive. Additionally, for comparison purposes, Ni/Al2O3-based catalysts prepared via wetness impregnation were synthesized with different Ni loadings. Analytical techniques were used for the characterization of the systems. The best results in terms of activity were as follows: Hydrotalcite with Ce promoter > Hydrotalcite without Ce promoter > 25Ni/Al2O3 > 13Ni/Al2O3. Hydrotalcite, with a Ce/Al atomic ratio of 0.22 and a Ni content of 23 wt%, produced 7.74 mmol CH4 min-1·gcat at 473 K under visible light. Moreover, this catalyst exhibited stable photocatalytic activity during a 24 h reaction time with a CO2 conversion rate of 65% and CH4 selectivity of >98% at 523 K. This photocatalytic Sabatier enhancement achieved activity at lower temperatures than those reported in previous publications.

| S-EPMC10488339 | biostudies-literature

Preparation of Ni based mesoporous Al2O3 catalyst with enhanced CO2 methanation performance.

Project description:A Ni based mesoporous γ-Al2O3 (MA) catalyst was prepared via partial hydrolysis without organic surfactants and employed in the carbon dioxide methanation reaction. The obtained catalysts were characterized by N2 adsorption-desorption, H2-TPR, XRD, XPS, TG, SEM and TEM-EDS techniques. CO2 methanation was performed in a fixed-bed reactor. A high surface area of MA with excellent hydrothermal stability was obtained, which promoted the dispersion of nickel species, producing a better catalytic performance. Incorporation of more NiO species into the Ni/MA catalyst increased the amount of active metallic Ni sties, further improving the catalytic activity and CH4 selectivity. Moreover, the monolithic skeleton of MA with fabric-like walls suppressed the aggregation of active metallic Ni sites and carbon deposition, enhancing the catalyst's stability, which provides a new insight for potential industrial applications.

| S-EPMC9061876 | biostudies-literature

Decomposition of Cyclohexane on Ni₃Al Thin Foil Intermetallic Catalyst.

Project description:Micro-grained thin foils made of Ni₃Al intermetallic alloy were fabricated, according to a previously described procedure, and tested as catalyst for decomposition of cyclohexane. The conversion efficiency of the catalyst was evaluated in a synthetic air atmosphere, and found to be as high as 98.7% ± 1.0% at 600 °C and 86.7% ± 3.6% at 500 °C. During the reaction, the growth of carbon nanofibers on the catalysts surface was observed. The chemical and phase composition of the nanofibers was investigated with scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), finding them to be made of graphitic carbon. Additionally, nanoparticles of nickel appear to be incorporated in the fibers. The obtained material is promising for large scale fabrication in industrial applications because of its high efficiency in the hydrocarbon decomposition, the simple fabrication procedure, and the form of self-supporting foils with the presence of additional carbon nanofibers that increase its efficiency.

| S-EPMC5456010 | biostudies-other

Complex Crystallization Kinetics of a Mg-Al Hydrotalcite and Their Practical Implications from the Process Point of View.

Project description:Hydrotalcites are an important class of layered materials, displaying ion-exchange, adsorption, and base catalytic properties. The crystallization kinetics for hydrotalcites are however hardly available. Nevertheless, as their reconstruction from the oxides (also called as "memory effect") is considered a synthesis route, this can be used to study the crystallization phenomena. This note looks at the reconstruction kinetics of a Mg-Al hydrotalcite using previously reported kinetic expressions. It was found that high temperature is beneficial if the process is controlled by nucleation. The temperature effect is less obvious when the process reaches a diffusional control regime. For example, temperature is beneficial to shorten the processing time in a nucleation-regime conversion (e.g., 40%). However, to achieve a high conversion (e.g., 98-99%), an intermediate temperature shows the optimal condition, i.e., shortest processing time. The work shows useful side effects of diffusional control. It also highlights the importance of obtaining the kinetics over the entire range for process optimization and, finally, emphasizes that both parameters in the Avrami-Erofe'ev model impact the time required to achieve a given conversion. Directions for further studies to understand the kinetic-process relationships have been highlighted.

| S-EPMC8675131 | biostudies-literature

UV- and visible-light photocatalysis using Ni-Co bimetallic and monometallic hydrotalcite-like materials for enhanced CO2 methanation in sabatier reaction.

Project description:The CO2 catalytic reduction activities of four different Co-modified Ni-based catalysts derived from hydrotalcite-like materials (HTCs) prepared by co-precipitation method were investigated under thermal and photocatalytic conditions. All catalysts were tested from 473 to 723 K at 10 bar (abs). The light intensity for photocatalytic reactions was 2.4 W cm-2. The samples were characterized to determine the effect of morphological and physicochemical properties of mono-bimetallic active phases on their methanation activity. The activity toward CO2 methanation followed the next order: Ni > Co-Ni > Co. For the monometallic Ni catalyst an increase of a 72% was achieved in the photo-catalytic activity under UV and vis light irradiation at temperatures lower by > 100 K than those in a conventional reaction. Co-modified Ni based hydrotalcite catalysts performed with stability and no deactivation for the 16 h studied under visible light for methanation at 523 K due to the presence of basic sites.

| S-EPMC10412882 | biostudies-literature

Selective Coupling of Bioderived Aliphatic Alcohols with Acetone Using Hydrotalcite Derived Mg-Al Porous Metal Oxide and Raney Nickel.

Project description:Fermentation of sugars to the so-called ABE mixture delivers a three component mixture of shorter chain oxygenates: acetone, n-butanol and ethanol. In order to convert these into liquid transportation fuels that are analogous to the currently used fossil energy carriers, novel catalytic chain elongation methods involving C-C bond formation are desired. Herein we report on a simple, non-noble-metal-based method for the highly selective coupling of 1-butanol and acetone into high molecular weight (C7-C11) ketones, as well as ABE mixtures into (C5-C11) ketones using the solid base Mg-Al-PMO in combination with small amount of Raney nickel. Upon hydrodeoxygenation, these ketones are converted to fuel range alkanes with excellent carbon utilization (up to 89%) using Earth abundant metal containing catalysis.

| S-EPMC6156109 | biostudies-literature