Biomass waste as an alternative source of carbon and silicon-based absorbents for CO capturing application.

The production of low-cost solid adsorbents for carbon dioxide (CO) capture has gained massive consideration. Biomass wastes are preferred as precursors for synthesis of CO solid adsorbents, due to their high CO adsorption efficiency, and ease of scalable low-cost production. This review particularly focuses on waste biomass-derived adsorbents with their CO adsorption performances. Specifically, studies related to carbon (biochar and activated carbon) and silicon (silicates and geopolymers)-based adsorbents were summarized. The impact of experimental parameters including nature of biomass, synthesis route, carbonization temperature and type of activation methods on the CO adsorption capacities of biomass-derived pure carbon and silicon-based adsorbents were evaluated. The development of various enhancement strategies on biomass-derived adsorbents for CO capture and their responsible factors that impact adsorbent's CO capture proficiency were also reviewed. The possible CO adsorption mechanisms on the adsorbent's surface were highlighted. The challenges and research gaps identified in this research area have also been emphasized, which will help as further research prospects.