• Pyrolysis is the preferred method to produce CO 2 adsorbents using biowastes. • The kinetic models accurately reproduced the experimental CO 2 capture performance. • Cork- and rice husk-based adsorbents do not deactivate over five cycles. • The CO 2 uptake from cement plant flue gas was higher than expected. The multicyclic kinetic performance and equilibrium CO 2 adsorption capacities of different biowaste-based adsorbents were measured experimentally, modelled and compared using pure CO 2 streaming and cement plant flue gas. Biowaste-based adsorbents used for CO 2 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 CO 2 -capturing adsorbents from tested biowastes. These adsorbents can reach equilibrium CO 2 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 CO 2 adsorption on biowaste-based adsorbents were calculated and compared to identify the impact of micropores and mesopores on separation performance.
Amorim et al. (Sun,) studied this question.