Using Adhesives to Capture Microplastics from Water

Abstract

Microplastic pollution is omnipresenthaving been found in our land, air, food, and water. Over the last two decades, both identifying microplastics and sleuthing their sources has been a major research focus. Moving forward, the next goal should be remediation. Although removing microplastics from the environment is impractical, developing methods that prevent their release into the environment is essential. Herein, we report an approach for removing microplastics from water using a pressuresensitive adhesive. Specifically, we demonstrate that shaking zirconium silicate beads coated with poly(2-ethylhexyl acrylate) in aqueous suspensions containing polystyrene microplastics (10 μm) can remove up to 99% of the microplastics within 5 min. We show that the adhesive molar mass (ranging from 93−950 kg/ mol) is invariant with respect to removal efficiency at 5 min, as quantified by flow cytometry. Preliminary results suggest these adhesives can bind other microplastics as well, including nonpolar polymers (e.g., polyethylene, micronized rubber) and polar polymers (e.g., nylon, polyethylene terephthalate). Overall, this proof-of-concept study demonstrates a promising approach for remediating microplastics from aqueous suspensions using adhesives.

Enhancing microplastic capture efficiencies with adhesive coatings on stainless-steel filters

“…Consequently, the adhesives can, over time, move across and off the coated substrate, leading to uneven coatings and shedding. We observed this undesirable phenomenon in our previous system 23 with P EH -coated zirconium silicate beads (Fig. 1A and Fig.…”

“…Once deposited, the solvent quickly evaporates, producing a more even coating than the original solvent-casting methods. 23 The coated SS beads were stirred in an aqueous suspension of microplastics for 18 h to compare to the zirconium silicate beads. The SS coatings appeared more stable via scanning electron microscopy (SEM), though some evidence of adhesive migration was still visible (Fig.…”

“…22 Similarly, we previously reported coating zirconium silicate beads with a pressure-sensitive adhesive ( poly(2-ethylhexyl acrylate), P EH ) to capture microplastics from water, including PS, poly(ethylene terephthalate), nylon-12, and rubber. 23 Pressure sensitive adhesives 24 are appealing materials for coatings because they can quickly conform to and wet materials such as microplastics. Although high removal efficiencies (>99%) of PS microplastics were observed within 5 min, the concentrations were high (1 g L −1 ; approx.…”

Removing microplastics from aquatic environments: A critical review

“…Chazovachii et al. indicated that shaking zirconium silicate beads coated with poly(2-ethylhexyl acrylate) in aqueous suspensions containing PS−MPs (10 μm) could remove up to 99% of the MPs within 5 min[ 52 ]. Solar energy was used to drive the removal of MPs in aquatic environments, in which the sunlight was focused by high-density glass spheres to induce convection and form microbubbles at the interface.…”

The measurement of food safety and security risks associated with micro- and nanoplastic pollution

“…Currently this method has only been used to compare the degradative effects of MP digestion methods, but represents a promising technique that can be adapted to other uses. Adhesive coated glass slides and beads have also been validated to successfully extract MPs comprised of PS, PE, PA, PET and micronized rubber from an aqueous matrix [168]. However, this method may not be well adapted to MNP removal from complex matrices.…”