Design and fabrication of bubble-assisted chitosan-based aerogels with promising macroporous structures for excellent oil-water separation capability

Chitosan-based aerogels garnered significant attention for oil/water separation applications due to their inherent biodegradability and renewability. In this study, we presented a novel bubble-assisted chitosan aerogel composite incorporating graphene oxide (GO) and silica nanoparticles (SiO₂). The poly-methyltrichlorosilane modulated foaming chitosan-GO-SiO₂ aerogel (FCGSA-PMTS) exhibited a unique macroporous structure with low density (8–10 mg·cm⁻³), high specific surface area (320.8 m²·g⁻¹), and excellent hydrophobicity. Meanwhile, the FCGSA-PMTS also demonstrated superior mechanical properties, including high compressibility, excellent elasticity, and outstanding fatigue resistance, retaining 95 % of its initial compression strength after 250 loading cycles. Sorption studies revealed excellent sorption capacity for various oils, with absorption ratios ranging from 35 to 85 times its weight. Notably, the FCGSA-PMTS maintained 94 % of its initial sorption performance even after 10 reuse cycles. Furthermore, continuous separation experiments verified that separation efficiencies and flux were approximately 99.6 % and 35,000 L·m⁻²·h⁻¹ , respectively. Therefore, FCGSA-PMTS showed great potential in large-scale environmental cleanup and wastewater treatment applications.