An overview of the properties of nanofilters derived from cellulose nanofibers for the adsorption of air pollutants

Pollution from airborne particles is one of the most important threats to human and environmental health in the world. Today, industrial air filters use synthetic polymers based on oil and chemicals, these materials are incompatible with the environment and lead to secondary pollution. Therefore, the development of the use of new materials in the fabrication of air filters, which is not only environmentally friendly but also renewable, is a vital need. For this reason, in recent years, many researches and studies have been done to replace cellulose nanofiber (CNF) with synthetic fibers such as glass nanofibers, activated carbon, and plastic polymersnanofibers in the manufacture of air filters. CNF has many advantages such as biodegradability, cheapness, low density, and network structure that can compete with synthetic nanofibers. Therefore, this review study aims to investigate the general use of CNF for the adsorption of particulate matter (PM) and carbon dioxide (CO2) in the air. The results showed that CNF increase the adsorption efficiency of CO2 and PM due to the presence of active hydroxyl groups on the surface as well as high specific surface area. In addition, the nanofilters made of CNF have a lower pressure drop than filters on the market due to their small pore diameter.