Catalytic Reaction of Carbon Dioxide with Methane on Supported Noble Metal Catalysts

• Main Author: András Erdőhelyi
• Format: Article
• Language: English
• Published: MDPI AG 2021-01-01
• Series: Catalysts
• Subjects: supported noble metal catalysts; dry reforming of methane; CO₂ + CH₄ reaction; dissociation of CO₂
• Online Access: https://www.mdpi.com/2073-4344/11/2/159

The conversion of CO₂ and CH₄, the main components of the greenhouse gases, into synthesis gas are in the focus of academic and industrial research. In this review, the activity and stability of different supported noble metal catalysts were compared in the CO₂ + CH₄ reaction on. It was found that the efficiency of the catalysts depends not only on the metal and on the support but on the particle size, the metal support interface, the carbon deposition and the reactivity of carbon also influences the activity and stability of the catalysts. The possibility of the activation and dissociation of CO₂ and CH₄ on clean and on supported noble metals were discussed separately. CO₂ could dissociate on metal surfaces, this reaction could proceed via the formation of carbonate on the support, or on the metal–support interface but in the reaction the hydrogen assisted dissociation of CO₂ was also suggested. The decrease in the activity of the catalysts was generally attributed to carbon deposition, which can be formed from CH₄ while others suggest that the source of the surface carbon is CO₂. Carbon can occur in different forms on the surface, which can be transformed into each other depending on the temperature and the time elapsed since their formation. Basically, two reaction mechanisms was proposed, according to the mono-functional mechanism the activation of both CO₂ and CH₄ occurs on the metal sites, but in the bi-functional mechanism the CO₂ is activated on the support or on the metal–support interface and the CH₄ on the metal.