Magnetic technique clears more than 95 percent of microscopic plastic pollution in minutes, offering promise for drinking water and wastewater systems.
SEOUL — Researchers at Pusan National University say they have developed a water-treatment method capable of removing microscopic plastic pollution in just 10 minutes, a breakthrough that could reshape how drinking water and wastewater are treated in the future.
The team announced on Jan 12 that its process eliminates more than 95 percent of microplastics and nanoplastics by using plate-shaped iron-oxide magnetic nanoparticles. When exposed to a magnetic field, the particles rapidly draw plastic fragments together, allowing them to be removed with speed and efficiency that conventional methods cannot achieve.
The findings were published online on Dec 24 in the Journal of Environmental Management.
RELEVANT SUSTAINABLE GOALS
A Growing Threat Too Small to Filter
Nanoplastics — fragments measuring tens to hundreds of nanometers — have emerged as a major environmental concern. Their small size allows them to evade standard filtration and sedimentation systems, enabling them to spread through rivers, oceans, and wastewater networks and potentially accumulate in the human body.
“Nanoplastics measuring tens to hundreds of nanometers have emerged as a new environmental threat, but filter-based methods struggle to remove them,” said Dr Chung Sung-wook, who led the research team. “This offers a way to clear ultra-fine contaminants quickly and at high efficiency.”
Unlike larger plastic debris, these particles are invisible to the naked eye and difficult to capture, making them one of the most persistent forms of plastic pollution.
Why Shape Matters in Magnetic Cleanup
A key advance in the research lies in particle design. Instead of relying on commonly used spherical magnetic particles, the scientists engineered thin, plate-like nanoparticles.
The change in geometry significantly increases the contact area between the magnetic particles and plastic fragments. This strengthens the interactions that allow plastics to bind to the particles.
When an external magnetic field is applied, the plate-shaped particles cluster together, trapping additional plastics in what the researchers describe as “dynamic confinement.” The result is rapid aggregation and removal of contaminants that would otherwise remain suspended in water.
Reusable Design With Lower Environmental Cost
The team also chemically modified the surface of the nanoparticles to improve their ability to bond with plastic materials. Importantly, the system was designed so the particles can be magnetically recovered after use and reused multiple times.
This feature reduces both operating costs and environmental impact, a critical consideration for large-scale water treatment and cleanup efforts.
The study mapped the entire process, from nanoparticle design and scale-up synthesis to the removal mechanism itself, positioning the technology for potential deployment beyond the laboratory.
According to the researchers, the technology could be applied in municipal drinking water systems, wastewater treatment plants, environmental remediation projects, and industrial effluent treatment.
By addressing plastic pollution at a scale that has so far been difficult to manage, the approach offers a new tool for public health and environmental protection, areas of growing concern worldwide. The research was supported by Korea’s National Research Foundation and the Ministry of Trade, Industry and Energy.
As plastic pollution continues to fragment into ever-smaller particles, the ability to remove nanoplastics efficiently may prove essential for safeguarding water supplies in the years ahead.
