Fionn Ferreira is an 18-year old from West Cork, Ireland who was recently awarded 50,000 dollars in educational funding by Google Science Fair for his project that successfully removes microplastics from water.
His process involves the use of "magnetic liquid" called ferrofluid, that essentially bonds to the microplastics and allows for extraction by magnets.
Fionn's inspiration came during a leisurely walk along one of his hometown beaches. There he noticed a rock covered in oil, he then noticed small pieces of plastic, no longer than 5mm, attached to the stone. This got him thinking, he said. "In chemistry, like attracts like."
In Fionn's paper, he details his methodology. The process included "adding oil to a suspension containing a known concentration of microplastics, these then migrated into the oil phase. Magnetite powder was added. The resulting microplastic containing ferrofluid was removed using strong magnets."
Fionn estimated an ambitious 85 percent removal rate, but after nearly 1,000 tests it turns out that his method can actually remove up to 88 percent of microplastics. He states that fibers that were most affected were those from washing machines, the least affected being microplastics made up of polypropylene.
"I was alarmed to find out how many microplastics enter our water system and consequently the oceans." says Fionn. "This inspired me to try and find out a way to try and remove microplastics from waters before they even reached the sea."
After researching current methods for microplastic removal, Fionn said he found no method that could quickly and efficiently extract the microplastics. Seeing as the only methods being employed up to that time was carbon filtration systems and density separation. This information gave Fionn the motivation to pursue a more viable method.
Fionn's drive and determination are clearly evident in the success of this project. He states that being from a small, remote town he had to build his own equipment. "I found articles on the spectral workbench website very useful in the building of the spectrometer and the later analysis of the results." he says.
Here is a look at the summarized extraction process Fionn included in his project:
- 20ml of the desired plastic suspension was prepared as explained on page 11 This was done in a test tube.
- 0.5g of the magnetite powder was added to the test tube.
- The desired amount of oil (if any) was added to the tube.
- The tube was stoppered and inverted 20 times to allow the magnetite and oil to cling on to the plastic.
- The stopper was removed and the ferrofluid containing microplastics was removed using Neodymium magnets in a small test tube. Then the magnets were pulled out of the suspension, the ferrofluid was removed from the tube by removing the magnets from inside the tube allowing the magnetite to fall off into a waste container.
- The magnets were dipped into the suspension three times.
- The sample was then ready for analysis.
Fionn concludes in his submittal that the project was of course a success, he now looks forward to applying the methods on a larger scale and one day making a difference in our oceans.