Mechanically robust and flame-resistant cellulose nanofiber aerogels for efficient smoke pollutant adsorption

Smoke generated from incomplete combustion in the chemical industry contains a complex mixture of hazardous compounds that pose serious threats to both the environment and human health. In this study, a cellulose-based aerogel was developed for efficient smoke adsorption by integrating surface-functionalized multi-walled carbon nanotubes (MWCNT-P) with TEMPO-oxidized cellulose nanofibers (CNF) via ultrasonic dispersion and freeze-drying. The resulting composite aerogel exhibits exceptional adsorption performance, achieving removal efficiencies of 91.67 % for tar and 84.76 % for nicotine, significantly outperforming conventional adsorbents. The material also demonstrates excellent mechanical robustness, sustaining a compressive strength of 150 kPa at 80 % strain, together with a limiting oxygen index (LOI) of 24.52 % indicating self-extinguishing capability. Furthermore, the aerogel retains 83 % of its initial adsorption capacity after 15 smoke adsorption-desorption cycles, demonstrating outstanding reusability. These multifunctional properties, combined with the renewable and lightweight nature of the material, position the aerogel as a promising candidate for sustainable smoke filtration and industrial air purification applications.