Hierarchical nanostructured carbons as CO2 adsorbents

MONTIEL-CENTENO, KIARA; BARRERA, DEICY; VILLARROEL-ROCHA, JHONNY; MORENO, M. SERGIO; SAPAG, KARIM

ADSORPTION-JOURNAL OF THE INTERNATIONAL ADSORPTION SOCIETY

SPRINGER

Año: 2019 vol. 25 p. 1287 - 1297

0929-5607

Synthesis and characterization of hierarchical carbon materials, CMK-5 type, with high specific surface areas and largepore volumes is reported and tested in CO2adsorption. These materials were successfully synthesized by the nanocastingprocess using a hard silica template SBA-15, furfuryl alcohol (FA) as carbon precursor, and 1,3,5-trimethylbenzene (TMB)as solvent. The percentage of FA, and the FA:TMB volume ratio were the synthesis parameters evaluated to determine theaccurate amounts to impregnate the pore walls of the template. Both parameters influence the formation of carbon materialswith a 2D porous structure and hexagonal tube array. CMK-5 materials achieved specific surface areas up to 2200 m2/g andtotal pore volumes ca. 2 cm3/g. The characterization techniques allowed us to establish a correlation between the differenttextural, structural and morphological properties and the carbon dioxide adsorption capacity. The CO2adsorption capacityat 308 K up to 1 bar has a strong relationship only with the micropore volume, but at higher pressure (up to 10 bar) theCO2adsorption capacity depends not simply on the amount of micropores but also of the small mesopores present in thesecarbons, reaching a maximum value of 7 mmol/g, at 308 K and up to 10 bar.