Conversion of fruit waste-derived biomass to highly microporous activated carbon for enhanced CO₂ capture

Activated carbons were prepared from different Amazonian fruit waste-derived biomass residues from the Amazon to store CO₂ at low pressure. The samples were carbonized in under flowing N₂ flow atmosphere and activated with KOH. The carbon materials obtained were physically and structurally characterized by the analysis of N₂ isotherms for textural characterization, X-ray fluorescence (XRF), ash content, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and applied for CO₂ adsorption. Temperature programmed desorption (TPD), the isosteric heat were also calculated. The values of the specific surface area (S_BET) ranged from 1824 to 2004 m²/g, and the total pore volume varied between 0.68 and 0.79 cm³/g. These results confirm that the obtained activated carbons are microporous materials. The highest CO₂ adsorption under the pressure of 1 bar was achieved in activated carbon derived from andiroba seeds ANKO1, the adsorption of carbon dioxide at 1 bar was being 7.18 and 4.81 mmol/g at 273 K and 298 K, respectively. As a result, the most important factor in the preparation of activated carbon for CO₂ capture is primarily rich in extremely the high amount of small micropores.