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© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.

Abstract

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

Details

Title
Dry Reforming of Methane (DRM) over Hydrotalcite-Based Ni-Ga/(Mg, Al)Ox Catalysts: Tailoring Ga Content for Improved Stability
Author
Elnour, Ahmed Y 1   VIAFID ORCID Logo  ; Abasaeed, Ahmed E 1   VIAFID ORCID Logo  ; Fakeeha, Anis H 1   VIAFID ORCID Logo  ; Ibrahim, Ahmed A 1   VIAFID ORCID Logo  ; Alreshaidan, Salwa B 2 ; Al-Fatesh, Ahmed S 1   VIAFID ORCID Logo 

 Chemical Engineering Department, College of Engineering, King Saud University (KSU), P.O. Box 800, Riyadh 11421, Saudi Arabia; [email protected] (A.Y.E.); [email protected] (A.E.A.); [email protected] (A.H.F.) 
 Department of Chemistry, Faculty of Science, King Saud University (KSU), P.O. Box 800, Riyadh 11451, Saudi Arabia; [email protected] 
First page
721
Publication year
2024
Publication date
2024
Publisher
MDPI AG
e-ISSN
20734344
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3120550964
Copyright
© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.