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

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

doi:10.3389/fchem.2020.00317

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.

Highlights

Methane (CH4) is the main component of natural and biogas
It can be seen that the relative intensities of all the diffraction peaks of Fe supported on the La2O3 + ZrO2 catalyst were more pronounced compared with those of the other catalysts
The results show the effect of doping the primary support (ZrO2) for the single metal-supported catalysts as well as the effect of adding

Summary

Introduction

Methane (CH4) is the main component of natural and biogas. Its use as a feed is expected to increase in the current year due to greenhouse gas effects (Fakeeha et al, 2015; Calgaro and Perez-Lopez, 2019). Emissions of greenhouse gases like CH4 contribute aggressively to environmental issues. Methods of transforming CH4 into handy products are worthy from the prospect of safety and the economic point of view of generating value-added fuels and chemicals (Ashok et al, 2008; Muhammad et al, 2018; Zhang et al, 2018). In this context, a direct approach is chosen for hydrogen (H2) and elemental carbon production, as given in Equation (1).

Methods

Results

Conclusion