Antimicrobial Air Filter Fabrication Using a Continuous High-Throughput Aerosol-Based Process

Abstract

A continuous high-throughput aerosol-based method for fabrication of antimicrobial air filters using natural antimicrobial nanoparticles was developed. We used the nebulization and electrospray methods for deposition of nanosized antimicrobial substances on pristine filter media. The roll-to-roll process was introduced for high-throughput fabrication of antimicrobial filters, and electrospray generation and dispersion equipment were used for high performance. The present method covers a filter area of 4500 mm 2 at one time with uniform deposition. The characteristics of the airborne particles generated by nebulization and the electrospray method were evaluated using a scanning mobility particle analyzer (SMPS) and scanning electron microscopy (SEM). Furthermore, filter performance, such as the pressure drop and antimicrobial efficiency, was examined. The pressure drop of the antimicrobial filter showed a general increasing trend with amount of deposited antimicrobial particles. When 2.64 and 3.52 µg mm -2 of antimicrobial particles were loaded on pristine filter media, the measured antimicrobial efficiency of the filter was over 99.5% based on a 24-h contact time. This study provides useful information for the development of a high-throughput production process for antimicrobial air filtration systems.

Electrospun nanofibers of polyvinylidene fluoride incorporated with titanium nanotubes for purifying air with bacterial contamination

“…Air, widespread with bioaerosols ranging from airborne viruses, bacteria, fungi, to pollens, ensues in various diseases including allergies when inhaled. Low settling velocity and minute size of the particles are the major reason for these particles to remain in the atmosphere for a longer duration than other aerosols (Bush and Portnoy 2001 ; Kang et al 2016 ; Lee and Liao 2014 ). Bioaerosols have their major contribution in hospitals, poultry farming, waste recycling units involving composting, biotechnology, tanning, etc.…”

“…Filtration systems are being developed among which wet scrubbers, electrostatic precipitation, gravity precipitation, and cyclotrons provide high efficiency towards particles less than 1 μm (Tabe 2014 ), where these approaches are undertaken to either inactivate or eliminate microbial interaction thereby preventing infections. Some of the common attempts include the usage of an electric precipitator, sterilization through ultraviolet radiation, and antibacterial filters (Kang et al 2016 ).…”

“…The latter, the aerosol-based process, involves the loading of the antibacterial components in the pristine filter thereby integration into a uniform single filter. The mechanism of working is analogous to the conventional air filters in which airborne particles are collected on the filter medium where the promising criterion in these filters is the solid antimicrobial coatings in pristine air filters (Haase et al 2017 ; Kang et al 2016 ).…”

Photothermal Electrospun Nanofibers Containing Polydopamine-Coated Halloysite Nanotubes as Antibacterial Air Filters

“…Antibacterial properties have been imparted to air filters via the coating of antibacterial agents onto the surfaces of nanofibers by dip coating, aerosol-based processes, or the integration of the antimicrobial agents into the electrospinning precursor solutions. − Silver- and titanium-based nanoparticles, − carbon nanotubes, and natural plant extracts − have been incorporated into electrospun nanofibers, resulting in antibacterial air filters. Bioaerosol particles that are captured on the air filter medium are inactivated via the biochemical toxicity provided by the incorporated antibacterial agents.…”