The aminosilane functionalization of cellulose nanocrystal aerogel via vapor-phase reaction and its CO2 adsorption characteristics

摘要

The cellulose nanocrystal (CNC) aerogel was functionalized using aminosilane via vapor-phase reaction and then the modified CNC aerogel was characterized by several techniques such as Fourier transform infrared spectroscopy, FE-SEM, and elemental analysis. Finally, the CO2 adsorption on the aminosilane-grafted CNC aerogel was featured using a dual-site Langmuir adsorption model. The result showed triethylamine significantly enhanced the amine loading, being 7.06 mmol g(-1) at 120 degrees C. The primary amine groups in the aminosilane survived the vapor-phase reaction. The amine groups were homogeneously distributed inside the aerogel due to its porous structure. The dual-site Langmuir model could well describe its CO2 sorption characteristics. The adsorption capacity was up to 2.57 mmolCO(2) g(-1) at 25 degrees C and 101.33 kPa, of which the chemisorption entirely dominated, and it decreased only 3%-4% after six runs. Therefore, these features positively suggested the vapor-phase reaction provided a new and feasible method to functionalize CNC aerogel for the capture of CO2.