(722h) Design of High Efficiency PVDF-Peg Hollow Fibers for Air Filtration of Ultrafine Particles

The particulate matter (PM) air pollution has become a
global issue in the last few decades. Various techniques, such as electron spun
air filters have been developed to remove PM from the air. However, limited
studies focused on filtration of small particles ( < 0.3 mm)
which are more toxic to human. Compared to conventional fibers filter media,
hollow fibers feature of self-supported properties with tunable pore sizes, making
hollow fibers a good candidate for filtration processes. Until now, limited
studies have worked on particle-laden gas filtration using hollow fibers. This
study reveals as the first attempt to apply hollow fibers for air filtration of
ultrafine particles. The asymmetric polyvinylidene fluoride - polyethylene
glycol (PVDF-PEG) hollow fibers with high gas permeance have been developed. In
order to increase the gas permeance of hollow fibers for air filtration, different
molecular weight of PEGs was added into spinning dopes. The addition of PEGs facilitate
the formation of loosely connected cross-section
and porous outer skin, thus enhances the gas permeance for air
filtration. Under the inside-out testing mode, all PVDF-PEG hollow fibers
display excellent filtration efficiency of 99.999% against polydispersed NaCl
particles with a geometric mean size of ~30 nm (Figure 1). This study may
provide useful insights for developing hollow fibers for air filtration with
the optimal operation conditions.