In a recent study published in the journal BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More, Gamal et al., explored a promising approach to capturing and utilizing carbon dioxide (CO2​), a major contributor to global warming. The researchers focused on enhancing the conversion of CO2​ into methane, a valuable energy source, using biochar-supported catalysts. Their key finding reveals that adding cerium to cobalt catalysts supported on sugarcane bagasse biochar significantly improves methane selectivity by 80% at 430°C, offering a sustainable pathway for CO2​ mitigation.

Global warming, driven by the accumulation of greenhouse gases like carbon dioxide in the atmosphere, poses a severe threat to our environment. To combat this, scientists are exploring methods to capture and transform CO2​ into useful products. One such method, CO2​ methanation, involves converting CO2​ into methane, a process that not only reduces emissions but also yields a valuable energy source.

Biochar, a solid product derived from the slow pyrolysisPyrolysis is a thermochemical process that converts waste biomass into bio-char, bio-oil, and pyro-gas. It offers significant advantages in waste valorization, turning low-value materials into economically valuable resources. Its versatility allows for tailored products based on operational conditions, presenting itself as a cost-effective and efficient More of biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More, has emerged as a potential catalyst support material due to its high surface area and porous structure. A variety of agricultural wastes, including sugarcane bagasse, can be used to produce biochar. Sugarcane bagasse biochar, with its porous structure, can enhance metal dispersion, leading to improved catalytic performance.

Study explored the use of sugarcane bagasse biochar to support cobalt catalysts for CO2​ methanation. They prepared catalysts with varying cobalt loadings and investigated the impact of cerium addition on catalytic activity. The researchers found that the addition of cerium significantly improved the catalytic performance of cobalt catalysts. The catalyst with 0.5 mmol of cobalt and 0.25 mmol of cerium per gram of sugarcane bagasse biochar (0.5Co-0.25Ce/SCBB) demonstrated the highest CO2​ conversion (60% at 500°C) and the best methane selectivity (80% at 430°C). This enhancement is attributed to cerium’s ability to improve metal dispersion and reduce particle size, as confirmed by TEM analysis.

The study highlights the potential of sugarcane bagasse biochar as a sustainable support for cobalt catalysts in CO2​ methanation. The addition of cerium plays a crucial role in enhancing catalytic activity, leading to higher CO2​ conversion and methane selectivity. The findings suggest that cerium can be used to boost the performance of other transition metals that may not exhibit high catalytic activity on their own in carbon dioxide methanation. This research paves the way for developing efficient and cost-effective catalysts for CO2​ utilization, contributing to the mitigation of global warming.

Source: Gamal, A., Tang, M., Chehimi, M. M., Khalil, A. M., Ozoemena, K. I., Abdullah, A. M., & Jlassi, K. (2025). Effect of metal loading and Ce addition on biochar-supported Co catalysts for CO2​ methanation. Biochar, 7(1), 73.