abstract
The incorporation of heteroatoms improves CO2 adsorption on carbon-based materials, but it can also provide some hydrophilic character to the bare-carbon frameworks, making the hypothesis of compet-itive CO2/H2O adsorption not negligible. In this respect, the CO2 capture is here evaluated through a deep characterization of the sorption properties of N-rich ordered mesoporous carbons under dry and moisture conditions, and in CO2/N2 gas mixtures. The nanocasting strategy is used to obtain N-rich CMK-3-type carbons in one pot by impregnating D-glucosamine hydrochloride, a carbon/nitrogen source, into an SBA-15 silica template followed by pyrolysis treatment at 600, 750, and 900 degrees C. The fine-tuning of the pyrolysis treatment aims to find the right proportion of micropores and N content, which are important features for selective CO2 adsorption. The highest surface amount of N (11.3 at.%), in particular of the pyridinic type, enhances the CO2/N2 selectivity (1.03 mmol/g of adsorbed CO2 from a 20% CO2 in N2), but also the undesired increment in the H2O uptake. CO2 uptake under competitive CO2/H2O conditions is better preserved with 8.3 at.% of surface nitrogen (1.55, 1.52, 0.61, and 0.89 mmol/g of CO2 at a relative humidity of 0, 25, 50, and 75%, respectively). Interestingly, the N-CMK-3 materials retain their capture properties over repetitive adsorption-desorption cycles in pure CO2. In this respect, a TGA-FTIR study is performed to monitor the reusability of the sorbents after CO2 capture from moist flue gases to assess the effectiveness of the reactivation procedure towards the removal of the adsorbed species.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
keywords
DENSITY-FUNCTIONAL THEORY; WATER-ADSORPTION; CARBONACEOUS MATERIALS; DIOXIDE SEPARATION; FACILE SYNTHESIS; GAS-ADSORPTION; POROUS CARBON; PORE-SIZE; FLUE-GAS; CAPTURE
subject category
Science & Technology - Other Topics; Materials Science
authors
Maruccia, E; Piovano, A; Lourenco, MAO; Priamushko, T; Cavallo, M; Bocchini, S; Bonino, F; Pirri, FC; Kleitz, F; Gerbaldi, C
Groups
acknowledgements
The RECODE project received funding from the EU's H2020 (R & I) programme under GA 768583. E.M., T.P., and F.K. acknowledge the funding support of the University of Vienna (Austria) . The authors are thankful to Dr. Salvatore Guastella for XPS measurement in the core facility (Department of Applied Science and Technology, Politecnico di Torino) , Dr. Marco Fontana for TEM images (Center for Sustainable Future Technologies (CSFT) , Istituto Italiano di Tecno-logia (IIT) ) as well as to Dr. Giuseppe Ferraro Center for Sustainable Future Technologies (CSFT) , Istituto Italiano di Tecnologia (IIT) ) and Dr. Remy Guillet-Nicolas (Department of Inorganic Chemistry-Functional Materials, University of Vienna) for technical support.