Filtration of Fine Particles in Atmospheric Aerosol with Electrospinning Nanofibers

In this study, a needleless electrospinning was studied, and the equipment was set up through theoretical simulation and a large number of experiments. The polylactic acid (PLA) nanofibers were prepared for filtering the aerosols by electrospinning. The PLA nanofibers mats were used as the middle layer to design the composite filter membranes. The atmospheric aerosols were used as dust sources in filtration test. The results showed that the filtration efficiency of the composite filter media was increased along with the thickness of nanofibers mats which was controlled by the collection time during the electrospinning. The filtration efficiency can be improved obviously by compositing with a thin layer of nanofibers. Moreover, the size distributions of atmospheric aerosols were monitored by the scanning mobility particle sizer spectrometer and the optical particle sizer. The size of particles in atmospheric aerosols was primarily distributed in range of less than 1 μm. It showed different changes with the mass concentrations of PM 2.5 (particulates with an aerodynamic diameter of ≤ 2.5 μm) for different sizes of fine particles. The amount of fine particles (less than about 60 nm) was decreased while the larger ones (> 60 nm) increasing along with the mass concentrations of PM 2.5 in atmospheric aerosols. That was due to the formation of the secondary atmospheric aerosols.