Carbon Aerogels with Excellent CO2 Adsorption Capacity Synthesized from Clay-Reinforced Biobased Chitosan-Polybenzoxazine Nanocomposites

The present study reports for the first time the use of biobased chitosan-polybenzoxazine (CTS-PBZ) as a precursor for high CO2 adsorbing carbon aerogels (CAs). Montmorillonite (MMT) is used to reinforce the CTS-PBZ aerogel. MMT-CTS-PBZ nanocomposite aerogels are synthesized using the freeze-drying technique and then cross-linked via ring-opening polymerization of benzoxazine followed by carbonization at 800 degrees C. Polybenzoxazine improves the structural stability for removing CO, from the environment even at a high pressure. The properties of polymeric and nanocomposite aerogels have been evaluated using X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The microstructure of the CAs is characterized by N-2 adsorption desorption measurements. mesoporous materials with pore sizes in the range of 2-7 nm and high BET surface area. The total pore volume of CAs is as large as 0.296 cm(3) g(-1), and the maximum BET surface area is 710 m(2) g(-1). Breakthrough curves of CO2 adsorption show high CO, adsorption capacity at ambient conditions and excellent CO2 adsorption desorption reversible performance with a maximum of 5.72 mmol g(-1). Adsorption isotherms and thermodynamic properties of CO2, adsorption are described.