Effect of Re Addition on the Water–Gas Shift Activity of Ni Catalyst Supported by Mixed Oxide Materials for H2 Production

Catalysts, Journal Year: 2023, Volume and Issue: 13(6), P. 959 - 959

Published: June 1, 2023

Water–gas shift (WGS) reaction was performed over 5% Ni/CeO2, Ni/Ce-5% Sm-O, Gd-O, 1% Re 4% Sm-O and Gd-O catalysts to reduce CO concentration produce extra hydrogen. CeO2 M-doped ceria (M = Sm Gd) were prepared using a combustion method, then nickel rhenium added onto the mixed oxide supports an impregnation method. The influence of rhenium, samarium gadolinium on structural redox properties materials that have effect their water–gas activities investigated. It found addition into Ni/CeO2 enhances surface area, reduces crystallite size CeO2, increases oxygen vacancy improves Ni dispersion surface. Moreover, leads increase in WGS activity Ni/CeMO catalysts. results indicate presents greatest activity, with maximum 97% carbon monoxide conversion at 350 °C. An area metallic this catalyst facilitation reactant adsorption. result X-ray absorption near-edge structure (XANES) analysis suggests donate some electrons resulting decrease oxidation state cerium. occurrence more Ce3+ higher vacancy, which alerts process surface, thereby increasing efficiency reaction.

Language: Английский

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Dry Reforming of Methane (DRM) over Hydrotalcite-Based Ni-Ga/(Mg, Al)Ox Catalysts: Tailoring Ga Content for Improved Stability

Catalysts, Journal Year: 2024, Volume and Issue: 14(10), P. 721 - 721

Published: Oct. 16, 2024

Dry reforming of methane (DRM) is a promising way to convert and carbon dioxide into syngas, which can be further utilized synthesize value-added chemicals. One the main challenges for DRM process finding catalysts that are highly active stable. This study explores potential use Ni-based modified by Ga. Different Ni-Ga/(Mg, Al)Ox catalysts, with various Ga/Ni molar ratios (0, 0.1, 0.3, 0.5, 1), were synthesized co-precipitation method. The tested reaction evaluate their activity stability. Ni/(Mg, its Ga-modified characterized N2 adsorption–desorption, Fourier Transform Infrared Spectroscopy (FTIR), H2-temperature-programmed reduction (TPR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) Raman techniques. test catalytic activity, at 700 °C, 1 atm, GHSV 42,000 mL/h/g, CH4: CO2 ratio 1, revealed Ga incorporation effectively enhanced catalyst Particularly, 0.3 exhibited best performance, CH4 conversions 66% 74%, respectively, an H2/CO 0.92. Furthermore, increased from 34% 46%, when testing 600 94% 96% was operated 850 °C. catalyst’s 20 h stream performance demonstrated great DFT alteration in electronic properties nickel upon incorporation, d-band center (Ga/Ni 0.3) shifted closer Fermi level, charge transfer Ni atoms observed. research provides valuable insights development emphasizes efficient conversion greenhouse gases syngas.

Language: Английский

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Ni-Based Catalysts: Synthesis and Applications Today

Catalysts, Journal Year: 2023, Volume and Issue: 13(6), P. 968 - 968

Published: June 2, 2023

Transition-metal-based catalysts are widely used in various processes, particular—nickel-based [...]

Language: Английский

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