Abstract: The multicyclic kinetic performance and equilibrium CO2 adsorption capacities of different biowaste-based adsorbents were measured experimentally, modelled and compared using pure CO2 streaming and cement plant flue gas. Biowaste-based adsorbents used for CO2 capture were synthesized from cork stoppers, grape marc,
and rice husks via pyrolysis and hydrothermal carbonization with and without lanthanum functionalization. The results demonstrate that pyrolysis is a more effective method than hydrothermal carbonization for producing CO2-capturing adsorbents from tested biowastes. These adsorbents can reach equilibrium CO2 carrying capacities of up to 63 mg/g at atmospheric temperature and pressure. No deactivation was observed over five adsorption/desorption cycles for cork- and rice husk-based adsorbents and the deactivation observed for grape marc-based adsorbents under flue gas can be overcome via lanthanum functionalization. Kinetic parameters for CO2
adsorption on biowaste-based adsorbents were calculated and compared to identify the impact of micropores and mesopores on separation performance.