Microplastics are a threat everywhere. They can be found on the highest peaks of the Earth, on the ocean floor, and even on the body of the reader of this article. Plastic does not disappear as it degrades, but breaks down into smaller and smaller pieces that circulate throughout ecosystems. In addition, it can have detrimental health consequences, especially for marine animals. The fact that they are very small particles, up to 150 times smaller than a human hair, is one of the major challenges in removing them. In the past, the only options were specialized membranes and other expensive technologies, but in recent years new strategies have begun to emerge.
Overwhelming power of ferrofluid
His name is Fionn Ferreira and in 2019 he won first prize at the Google Science Fair for his innovative system for cleaning microplastics. This his 20-year-old Irishman submitted a proposal based on the use of ferrofluids. His filters use oil-based ferrofluids and oxide particles, as microplastics tend to bond with metal particles. Once this process is complete, the ferrofluid attracts plastic particles paired with metal. This technology has demonstrated his 88% efficiency in water purification. The aim is to allow new filters to be integrated into existing equipment, from water purifiers to domestic washing machines. This is one of the main causes of microplastic shedding when washing synthetic clothing. One of Ferreira’s most promising strategies is to install these filters in the boat’s cooling system. Motorboats use seawater to cool their equipment and return it to the sea. In the future, the idea is that the ship will become a floating he filtering station that helps remove microplastics.
Bacteria could be the key
If there’s anything more ubiquitous than microplastics, it’s bacteria. The metabolic capabilities of these microorganisms already play an important role in water purification and are also playing a leading role in innovative renewable energy. They can metabolize sulfuric acid and of course polymers. Some of them were already able to metabolize lignin and wax, while others evolved to eat plastic. This approach is based on finding the most efficient bacteria in this sense to enable processes that degrade plastics both in landfills and in seawater. This bioengineering technology, which is still in its infancy, could help reduce some of the millions of tons of plastic that enter our oceans each year.
next generation filter
In addition to bacteria, plants may be used as an alternative to filter microplastics.The Finnish VTT Technical Research Center has developed a new nanocellulose membrane that can trap even the tiniest plastic particles. The colloidal and porous structure of this filter traps microplastics without the need for chemicals or mechanical action. Similar to Ferreira’s proposal, it could be integrated into washing machines to prevent microplastics from reaching wastewater and ultimately the ocean.
As always, the best strategy is to reduce plastic production. But in the meantime, these new technologies will help us fight this invisible and omnipresent enemy.
sauce: Guardian
