NOVO ADSORVENTE NANOESTRUTURADO HÍBRIDO DO TIPO AMINA/KIT-6 PARA CAPTURA DE CO₂

NEW HYBRID NANOSTRUCTURED ADSORBENT TYPE AMINE/KIT-6 FOR CO₂ CAPTURE. The present work functionalized KIT-6 mesoporous material with aminopropyltrimethoxysilane (APTMS) and tested its efficiency in CO₂ capture. The KIT-6 material was synthesized by hydrothermal method and functionalized via excess solvent in APTMS concentrations of 5 and 15% to obtain the hybrid adsorbents. All adsorbent materials were characterized by XRD, TGA/DTGA, DSC, N₂ adsorption/desorption, SEM and applied in the CO₂ capture, varying the temperature and pressure. The KIT-6 mesoporous structure at the hybrid adsorbents was kept. Variations in textural properties denoted that the organic molecules were incorporated in mesoporous structure. In the experiments, both chemisorption and physisorption were observed, reaching the best values at 25 ºC, indicating that the temperature influences the adsorption process. The experiments showed adsorbed amounts of up to 0.8 mmol/g at atmospheric pressure, displaying the efficiency of the chemisorption provided by the CO₂ interaction with the hybrid adsorbents. At high pressures, a predominance of physisorption was observed, demonstrating a better performance for the KIT-6 support, due to the superior textural properties. Finally, a well-ordered and functional hybrid adsorbent was successfully developed for the adsorption of carbon dioxide.

Keywords:
mesoporous adsorbent; KIT-6; adsorption; carbon dioxide