A Sustainable Recycling Alternative: Electrospun PET-Membranes for Air Nanofiltration

Abstract

Currently, the inappropriate disposal of plastic materials, such as polyethylene terephthalate (PET) wastes, is a major environmental problem since it can cause serious damage to the environment and contribute to the proliferation of pathogenic microorganisms. To reduce this accumulation, PET-type bottles have been recycled, and also explored in other applications such as the development of membranes. Thus, this research aims to develop electrospun microfiber membranes from PET wastes and evaluate their use as an air filter media. The solution concentrations varied from 20 to 12% wt% of PET wastes, which caused a reduction of the average fiber diameter by 60% (from 3.25 µm to 1.27 µm). The electrospun filter membranes showed high mechanical resistance (4 MPa), adequate permeability (4.4 × 10−8 m2), high porosity (96%), and provided a high collection efficiency (about 100%) and low-pressure drop (212 Pa, whose face velocity was 4.8 cm/s) for the removal of viable aerosol nanoparticles. It can include bacteria, fungi, and also viruses, mainly SARS-CoV-2 (about 100 nm). Therefore, the developed electrospun membranes can be applied as indoor air filters, where extremely clean air is needed (e.g., hospitals, clean zones of pharmaceutical and food industry, aircraft, among others).

Electrospun Poly(ethylene Terephthalate)/Silk Fibroin Composite for Filtration Application

“…The solvents in this study had to be selected regarding electrospinnability. PET has been already electrospun from a trifluoroacetic acid (TFA), a mixture of TFA/DCM [ 44 , 66 , 67 ] in various portions or from HFIP and HFIP/DCM [ 33 , 68 ]. In the case of silk fibroin, it has been proven many times that the SF could be electrospun from aqueous solutions only with the aid of an auxiliary polymer [ 69 , 70 ]; however, it was successfully electrospun from formic acid (FA), TFA, and HFIP [ 58 , 70 , 71 ].…”

“…Different polymeric materials have been used for producing electrospun membrane for filtration including cellulose acetate (CA) [ 37 ], silk fibroin (SF) [ 38 ], poly(lactic acid) (PLA) [ 39 ], polyamide-6 (PA6), poly(vinyl alcohol) (PVA) [ 40 ], polyvinylacetate (PVAc) [ 37 ], polyacrylonitrile (PAN) [ 41 , 42 ], polyvinylidene fluoride (PVDF) [ 43 ], or poly(ethylene terephthalate) (PET) [ 33 , 44 ].…”

Nanofibers functionalized with surfactants to Eliminate SARS-CoV-2 and other airborne pathogens

“…Their fibers ranged between 80 to 200 nm in diameter with a collection efficiency of 99,993% against 300 nm particles, at a velocity of 5 cm s -1 (AHN et al, 2006). Matulevicius and co-workers (2014) Electrospun nanofibers have excellent properties that enable the capture of efficient ultrafine particles (BONFIM et al, 2021a;ZHANG et al, 2017). Some of them are a large surface-area-to-volume ratio, low basis weight, nanoporous structures, and uniform electrospun fibers (MATULEVICIUS et al, 2014).…”

Circulatory Management of Polymer Waste: Recycling into Fine Fibers and Their Applications

“…The objective of the study of Bonfim et al [ 118 ] was to produce filter media with microfibers obtained from PET bottles waste for the highly efficient removal of nanoparticles present in the air. Electrospinning has been used as a fabrication technique.…”