Surface functionalization by grafted polyethylenimine onto regenerated cellulose derived from sugarcane bagasse by gamma irradiation for carbon dioxide gas capture

• Cellulose was successfully extracted and purified from sugarcane bagasse. • Native cellulose was successfully transformed into regenerated cellulose by dissolution and regeneration processes. • An amine-functionalized adsorbent was prepared by grafting with gamma irradiation for sustainable adsorbents of carbon dioxide gas. • Low-cost and environmentally friendly RC-g-PEI adsorbent was an outstanding choice for carbon dioxide gas capture. In this work, we prepared the amine-functionalized adsorbent by dissolving and regenerating cellulose I into cellulose II, commonly referred to as regenerated cellulose (RC). The porous RC was subsequently impregnated with polyethylenimine (PEI) on the surface using the grafting technique by gamma radiation. At a 10% (v/v) PEI concentration and 30 kGy radiation, the highest grafting rate of 59.14% is shown. FTIR was used to determine the presence of N-H stretching. XRD revealed an increase in crystallinity after grafting when compared to RC. After that, to confirm the presence of PEI by CHNS elemental, the results exposed increased nitrogen content from the amine groups. TGA showed the thermal decomposition behavior of the strong covalent bond between PEI and RC. The surface characterizations were observed that the amine was comprehensively modified on the surface of the inner pores of RC-g-PEI in the FESEM image, which corresponded with the CLSM image, with the reduced surface roughness after the amine impregnation. The N 2 adsorption-desorption isotherm was reported to be a type IV isotherm. Moreover, the CO 2 adsorption capacity of the RC-g-PEI sorbent reached 2.58 mmol/g at 50 °C under CO 2 atmosphere, and the surface functional groups of RC-g-PEI before and after CO 2 adsorption were studied using FTIR and XPS to specify the successful modification surface of amine onto RC using the gamma irradiation technique for carbon dioxide gas adsorption.