Capture of CO2 by vermiculite impregnated with CaO.

Abstract
Vermiculite samples were impregnated with different amounts of calcium oxide by the con- ventional thermal heating technique and subject to CO2 capture experiments in thermal analysis equipment. The amount of CO2 captured by calcium oxide increased from 13 g of CO2 per mol of CaO to 16.8 g of CO2 per mol of CaO when the experiments were carried out with pure calcium oxide and vermiculite impregnated with CaO (1:1), respectively. Integral isoconversional methods of Kissinger-Akahira-Sunose (KAS) and Osawa-Flynn-Wall (OFW) were used for the kinetic study of the process and good correlation coefficients were achieved. The apparent activation energy values showed that for low conversions (a < 0.3) the controlling step of the process is a mixed step where the chemical reaction and the dif- fusion of the reagents into the vermiculite have rates of the same order of magnitude (20 kJ < Ea < 40 kJ). For higher conversions values (a > 0.3) the apparent activation energy values suggest that the slow step is a chemical step (Ea> 40 kJ).
Description
Keywords
Calcium oxide, Isoconversional, Method, Kinetics
Citation
PEREIRA, M. H. S. et al. Capture of CO2 by vermiculite impregnated with CaO. Carbon Management, v. 13, p. 117-126, 2022. Disponível em: <https://www.tandfonline.com/doi/full/10.1080/17583004.2021.2023050>. Acesso em: 29 abr. 2022.