A new EU-funded project is set to test a system designed by Sweden’s KTH Royal Institute of Technology to break down microplastics from personal care products for implementation in homes and wastewater treatment plants.
As part of the Cleaning Litter by Developing and Applying Innovative Methods in European Seas (CLAIM) project, the researchers will harness the sun’s radiation to prevent oceans from microplastic contamination.
Though the exposure to sunlight can help naturally degrade plastics into harmless elements, the entire process is slow and time-consuming.
KTH Functional Materials division chair Joydeep Dutta said that the new system will be able to expedite the process by making more effective use of available visible light and ultraviolet rays from the sun.
The system involves coatings with a material of nano-sized semiconductors that help begin and speed-up a natural process called photocatalytic oxidation.
While conducting household tests, the nano material-coated filter systems will be placed at the exit of wastewater from homes, while for wastewater treatment plants, the devices will be used to initiate microplastics degradation after the traditional treatments are completed.
Photocatalytic oxidation with titanium oxide and zinc oxide semiconductors are used to convert volatile pollutants, oils and other substances into harmless elements such as water and CO2.
Photocatalysis activates the breakup of compounds by exciting electrons, which then results in water molecules to split into their constituent parts, hydrogen and oxygen.
The material is capable of capturing enough sunrays from a minimum of available light to initiate a reaction with the molecules of the plastic, following which the radicals exchange electrons with the atoms that comprise plastic molecules, thereby effectively pulling the contaminants apart into harmless compounds of CO2 and water.
The project will also include the deployment of floating booms at river mouths in Europe that would collect visible plastic waste.
Ferry routes in Denmark, the Gulf of Lyon, Ligurian Sea and Saronikos Gulf will be used to test a plastics measuring system that can be later integrated into shipping vessels.