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

Abstract

AbstractThe 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°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 mmolCO2 g−1 at 25°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.