Superhydrophobic cellulose-nanofiber aerogels from waste cotton stalks for superior oil–water and emulsion separation

Abstract Cellulose aerogel, a sustainable material characterized by low density and high porosity, demonstrates promising potential for addressing oil spill incidents. In this study, waste cotton stalk biomass was processed using formic acid and hydrogen peroxide to extract cellulose, resulting in the successful creation of a cost-effective aerogel. This material exhibits notable attributes: low density (21.1 mg cm −3 ), high porosity (91.5%), significant hydrophobicity (water contact angle of 147°), exceptional adsorption capacity (47.61 g g −1 ), and robust cycling performance (maintaining 94% adsorption capacity after 15 cycles). Moreover, the CNF/CS biomass aerogel boasts high mechanical strength and exceptional oil–water and emulsion separation properties. These characteristics position this aerogel as a promising solution for mitigating various sudden oil spill incidents, indicating its potential for widespread application.