Methane Decomposition Over ZrO2-Supported Fe and Fe-Ni Catalysts-Effects of Doping La2O3 and WO3

Anis H Fakeeha; Samsudeen Olajide Kasim; Ahmed Aidid Ibrahim; Abdulrhman S Al-Awadi; Eman Alzahrani; Ahmed Elhag Abasaeed; Ahmed E Awadallah; Ahmed Sadeq Al-Fatesh

doi:10.3389/fchem.2020.00317

Methane Decomposition Over ZrO₂-Supported Fe and Fe-Ni Catalysts-Effects of Doping La₂O₃ and WO₃

Front Chem. 2020 Apr 29:8:317. doi: 10.3389/fchem.2020.00317. eCollection 2020.

Authors

Anis H Fakeeha^{1

2}, Samsudeen Olajide Kasim¹, Ahmed Aidid Ibrahim¹, Abdulrhman S Al-Awadi¹, Eman Alzahrani³, Ahmed Elhag Abasaeed¹, Ahmed E Awadallah⁴, Ahmed Sadeq Al-Fatesh¹

Affiliations

¹ Chemical Engineering Department, College of Engineering, King Saud University, Riyadh, Saudi Arabia.
² King Abdullah City for Atomic and Renewable Energy (K.A.CARE), Energy Research and Innovation Center, Riyadh, Saudi Arabia.
³ Department of Chemistry, Faculty of Science, Taif University, Taif, Saudi Arabia.
⁴ Process Development Division, Egyptian Petroleum Research Institute, Cairo, Egypt.

Abstract

A leading method for hydrogen production that is free of carbon oxides is catalytic methane decomposition. In this research, Fe and Fe-Ni supported catalysts prepared by the wet impregnation method were used in methane decomposition. The effects of doping the parent support (ZrO₂) with La₂O₃ and WO₃ were studied. It was discovered that the support doped with La₂O₃ gave the best performance in terms of CH₄ conversion, H₂ yield, and stability at the test condition, 800°C and 4,000-ml h^-1 g^-1 cat. space velocity. The addition of Ni significantly improved the performance of all the monometallic catalysts. The catalysts were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), temperature-programmed reduction/oxidation (TPR/TPO), thermogravimetric analyzer (TGA), and microscopy (SEM and Raman) techniques. Phases of the different forms of Fe were identified by XRD. BET showed a drastic decline in the specific surface area of the catalysts with respect to the supports. TPR profiles revealed a progressive change in the valency of Fe in its combined form to the zero valence-free metal. The La₂O₃-promoted support gave the best performance and maintained good stability during the time on stream.

Keywords: Fe; Fe–Ni; La2O3 + ZrO2; Raman spectra; WO3 + ZrO2; graphitization; hydrogen; methane conversion.