Olive stone-derived biochar as a sustainable catalyst support for CO2 methanation

The hydrogenation of carbon dioxide (CO2) into methane presents a promising strategy for CO2 utilization. However, the large-scale implementation of this process remains limited by the lack of cost-effective and sustainable catalytic materials. This study explores the potential of biochar derived fr...

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Detalles Bibliográficos
Autores: Villardón Pérez, Alba, Alcázar Ruiz, Ángel, Cencerrero Fernández del Moral, Javier, Romero Izquierdo, Amaya, Sánchez Silva, María Luz, Dorado Fernández, Fernando
Tipo de recurso: artículo
Fecha de publicación:2025
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/43124
Acceso en línea:https://doi.org/10.1016/j.jcou.2025.103102
https://hdl.handle.net/10578/43124
Access Level:acceso abierto
Palabra clave:Chemical activation
CO2 methanation
Ni-based catalysts
Olive stone biochar
P2M
Sabatier reaction
Descripción
Sumario:The hydrogenation of carbon dioxide (CO2) into methane presents a promising strategy for CO2 utilization. However, the large-scale implementation of this process remains limited by the lack of cost-effective and sustainable catalytic materials. This study explores the potential of biochar derived from agro-industrial waste, specifically olive stones, as an innovative and eco-friendly support for Ni-based catalysts in CO2 methanation. Three different chemical activation methods (KOH, ZnCl2, and H3PO4) were applied to enhance the textural and structural properties of the biochar, significantly influencing its catalytic performance. Among the tested materials, KOH-activated biochar (10Ni-KOH) exhibited superior Ni dispersion, enhanced surface area, and an increased number of moderately strong basic sites, which are crucial for CO2 activation. This catalyst achieved a CO2 conversion of 72 % and a CH4 selectivity of 95.5 %, outperforming the other formulations. In contrast, biochar activated with H3PO4 led to the encapsulation of Ni particles within a phosphorus matrix (as demonstrated by TEM images), while ZnCl2 activation promoted the formation of Ni-Zn alloys (as indicated by XPS and XRD analysis), both of which hindered methanation efficiency. These findings highlight the transformative potential of biochar as a low-cost and sustainable catalyst support, offering a viable alternative to conventional materials for CO2 methanation. By leveraging agricultural residues, this approach not only contributes to circular economy principles but also enhances the economic and environmental feasibility of Power-to-Methane (P2M) technologies.