Aminosilanes grafted nanocrystalline cellulose from oil palm empty fruit bunch aerogel for carbon dioxide capture

Abstract

The modification of solid adsorbents with aminating agents amid severe climate change has been intensively studied. Previous organic carbon dioxide (CO2) sorbent like nanoporous activated carbon develops micropores but can be easily blocked by organic amine molecules during the impregnation process. Therefore, in this study, aminosilanes with different chain lengths and nitrogen (N) content were used in nanocrystalline cellulose (NCC) modification prior to solid adsorbent aerogel fabrication to investigate their effect on pore formation, surface area, thermal stability, and capacity of CO2 capture. The NCC derived from oil palm empty fruit bunch fiber (OPEFB) has been modified with 3-(aminopropyl) trimethoxysilane (APTMS), 3-(2-aminoethylamino) propyl-dimethoxymethylsilane (AEAPDMS), and N-(3-trimethoxysilylpropyl) diethylenetriamine (DET3) by grafting method, respectively. Based on the results, aerogel modified with the shortest chain length aminosilane, APTMS-NCC aerogel has a higher CO2 sorption (0.20 mmol/g adsorbent) than the unmodified NCC aerogel (0.10 mmol/g adsorbent). Meanwhile, the highest surface area properties and thermal stability are demonstrated by NCC grafted by the intermediate chain length aminosilane, AEAPDMS-NCC aerogel. Thus, our work concluded that NCC's modification with low and intermediate chain length and N content aminosilanes prior to aerogel fabrication improved the pore formation, surface area, and CO2 sorption of the aerogel. The aerogels from aminosilanes functionalized NCC could be developed as a new value-added product in the palm oil industry.

Keywords

• Nanocellulose
• Alkanolamines
• Modification of nanocellulose
• Solid adsorbent
• CO2 adsorption