Ultrahigh Adsorption of Toxic Substances from Cigarette Smoke Using Nanocellulose-SiO₂ Hybrid Aerogels

Abstract

A cellulose nanofiber-SiO2 hybrid aerogel cigarette (CSG) filter, which can be used for ultrahigh adsorption of toxic substances from cigarette smoke, was prepared based on the skeletal material of cellulose nanofibers (CNFs) with the help of a simple directional frozen technology. SEM and FTIR results confirmed the successful introduction of the SiO2 nanoparticles, and the application process of SiO2 nanoparticles did not influence the three-dimensional network structure of CSGs. Considering the practical application of the CSGs on the cigarette filter, the mechanical and thermal properties of the CSGs were investigated. The stress–strain and TG curves showed that the mechanical and thermal stability properties of the CSGs increased compared with the pure cellulose nanofiber aerogel without the introduction of SiO2 nanoparticles. The adsorption capacity of the CSG filter tips against toxic substances from cigarette smoke was systematically investigated. Compared with conventional cellulose acetate filter tips, the CSG filter tips performed well at adsorption of tar, TPM (total particulate matter), nicotine, and CO from cigarette smoke with removal efficiencies of 92.23, 90.25, 95.02, and 20.63%, respectively. Crucially, the preparation of CSGs needs no extra chemical agents, showing an eco-friendly process. These results suggest that CSGs display great potential working as an ideal candidate for mainstream smoke toxicant adsorption.

Fabrication of Cellulose Filters Incorporating Metal–Organic Frameworks for Efficient Nicotine Adsorption from Cigarette Smoke

“…After three adsorption cycles and cleaning, the FT-IR spectra of the UiO-66@CF materials and the characteristic band of the composite material were retained, and it was found that the peaks at 2918 and 2856 cm –1 disappeared after cleaning, which further proved the recyclability of the material (Figure S18b). Furthermore, UiO-66@CF was compared with other reported functionalized filters (Table S3), indicating that the nicotine adsorption efficiency of UiO-66@CF was higher than other materials. Moreover, the cost of UiO-66@CF as the filter was relatively cheaper than other reported materials (Table S4).…”

“…This can be explained by a diminished crystallinity of cellulose given the interaction of MOFs particles with free hydroxyl groups on the surface of cellulose fiber. 45 Among the prepared samples, UiO-66@CF presents the best flexibility and can bend without the formation of cracks observable by naked eyes. Additionally, it was also found that the toughness of the MOF@CF samples increased but the rigidity decreased after incorporating MOF particles.…”

“…The mechanical performance (stress–strain) changed after incorporating MOFs, making the resulting material more flexible. This can be explained by a diminished crystallinity of cellulose given the interaction of MOFs particles with free hydroxyl groups on the surface of cellulose fiber . Among the prepared samples, UiO-66@CF presents the best flexibility and can bend without the formation of cracks observable by naked eyes.…”

Advanced Materials Design for Adsorption of Toxic Substances in Cigarette Smoke

“…Cheng et al. [ 44 ] developed a CSG aerogel cigarette filter prepared using cellulose nanofibers modified with SiO 2 nanoparticles and investigated its adsorption properties for toxic substances. Compared to the conventional CAF, the CSG filter exhibited superior adsorption capacity for hazardous substances present in cigarette smoke, with removal rates of 92.2% (tar), 90.3% (total particulate matter, TPM), 95.0% (nicotine), and 20.6% (CO).…”

Biobased Aerogels Fabricated by the Ice Crystal Method for Smoke Purifying

“…However, among traditional cigarette filters, such as cellulose acetate cigarette filters, polypropylene cigarette filters, and polylactic acid cigarette filters, either low filtration efficiency or nondegradability cannot meet the current need for smoke filters. Consequently, to adsorb toxic chemicals from smoke, large amounts of functional purification materials are explored, such as silica, − zeolites, graphene and oxidized carbon nanocages, etc. Huang’s group investigated a nicotine surface-imprinted monolith for the selective removal of nicotine from smoke, and it exhibited a high adsorption performance with an adsorption efficiency of 99.43% .…”