Synthesis and characterization of a thermosensitive solid amine biomass adsorbent for carbon dioxide adsorption

A thermosensitive solid amine fiber SF-AM-co-NIPAM-HBP-NH2 was synthesized by grafting temperature-sensitive monomer N-isopropyl acrylamide (NIPAM) as well as acrylamide (AM) onto the surface of substrate sisal fiber, and further aminating with hyperbranched amine. FTIR, 13C NMR, SEM, EA and TGA were used to confirm the structure and chemical properties of the grafted fibers. Swelling ratio and CO2 adsorption-desorption experiment were investigated to verify the thermo-sensitivity of the grafted fibers and their CO2 adsorption-desorption behavior. Compared with conventional solid amine adsorbents regenerated around 140 °C, SF-AM-co-NIPAM-HBP-NH2 (1:1) with NIPAM could be regenerated at a much lower temperature of 60 °C, while still maintain a high CO2 adsorption capacity (2.61 mmol/g), comparable to that of SF-AM-HBP-NH2 (2.73 mmol/g) before NIPAM introduction. Its excellent regeneration property and the effect of energy consumption reduction make it possible to be used for CO2 adsorption in industrial process. •Biomass fiber was used as a renewable substrate for CO2 adsorbent preparation.•The adsorbent could have high CO2 adsorption capacity by amination.•The adsorbent showed obvious thermosensitive property, owing to the introduction of NIPAM.•The absorbent could be regenerated at 60 °C, much lower than 140 °C of conventional solid amine adsorbents.