Solid residues after gasification of agricultural residues as scalable and economical CO2 adsorption materials

Economical CO 2 adsorbents are gaining significant attention as viable solutions to combat climate change. This research assessed the CO 2 adsorption potential of solid residues following the gasification of bagasse (SR-Bagasse), bamboo (SR-Bamboo), and rice husk (SR-Rice husk) in various systems in Vietnam and Cambodia. Among these residues, SR-Bagasse showed the highest CO 2 adsorption capacity, followed by SR-Bamboo, while SR-Rice husk exhibited moderate performance. The CO 2 adsorption capacity at 25 °C with 100 % CO 2 flow varied from 6 % to 9.5 % of the adsorbent's weight. Under flue gas conditions (15 % CO 2 and 85 % N 2 ), the adsorption capacity ranged from 2 % to 5 %. Additionally, these chars demonstrated significant recyclability with 90 % of initial adsorption capacity retained after 30 cycles, making them comparable to several advanced CO 2 adsorbents studied previously. The highest performance of SR-Bagasse could be attributed to its substantial microporous and ultra-microporous volumes, with micropores serving as both CO 2 adsorption sites and conduits to ultra-micropores. This study's findings emphasize the potential for integrating energy production with the development of economical and scalable CO 2 adsorbents for industrial use. • Solid residues from biomass gasification as environmentally friendly and scalable CO 2 adsorbents. • Significant CO 2 uptakes (up to 9.5 wt% of the adsorbent) at 25 °C, 1 atm. • Remarkable recyclability following 30 cycles and exposure to moisture.