Cellulose nanofiber-based air filter with antibacterial property from sugarcane bagasse

Particulate matter or PM continues to be a problem for the quality of life and health of people worldwide. Especially PM2.5, these tiny PM can also carry chemicals, bacteria, microbes and viruses in the air into the body through the respiratory tract and lungs, and some particles may enter the bloodstream and cause many diseases. Wearing a mask when outside and using air purifiers when in the house is necessary for life. Therefore, we are interested in using cellulose nanofibers (CNF), extracted from bagasse, as the main material for producing air filters. CNF is a biomaterial that can be extracted from cellulose to obtain tiny fibers with a diameter of nanometers (5-20 nm). It has attractive properties such as strength, high specific surface area, biodegradability, lightweight, and low density. CNF contains nanometer-sized fibers. This results in low resistance to airflow. In addition, CNF has a high specific surface area; thus, it has a high ability to trap particles. In addition to the high filter efficiency, the antibacterial property is also an essential factor. Because when used for a long time, the air filter will become contaminated with microorganisms, and the accumulation of microorganisms on the filter also causes an increase in pressure drop, which decreases the filtration efficiency as well as causes health problems. Therefore we propose to develop CNF-based air filters with antibacterial properties. The CNF/Nano ZnO composite aerogel will be prepared by in situ deposition method that is ZnO will be synthesized using CNF as a template. Zn²⁺ will interact to the COO- functional group in CNF structure. Zn²⁺ in CNF hydrogel is converted to ZnO by a base solution (NH4OH) with microwaves assisted. The prepared composite hydrogel is then dried by freeze-drying. The effect of the Zn²⁺ concentration and reaction time on morphology, crystal structure, porosity, specific surface area, thermal stability, filter efficiency, and antibacterial activity of aerogel composite filters in both the presence and absence of UV light will be studied.