Alameda County Science and Engineering Fair

The Application of Using Ferrofluid to Extract Microplastics from the Ocean: During my junior year of high school, I participated in the Alameda County Science and Engineering Fair. Our team realized that large amounts of microplastics accumulate in the ocean. These small plastic particles less than 5 millimeters in diameter have been destroying the base of the oceans ecosystem, krill, causing instability throughout the food chain. Considering that these plastics take upward of 450 years to decompose, and there is no current way of extracting them, an efficacious solution is essential. That is why I worked with a team of two other students to develop a home made ferrofluid to extract these harmful microplastics. Baseline use of ferrofluid was recently demonstrated by Fionn Ferriera. That being said, his concepts were yet to be utilized in an applicable manner. We expanded upon his research with the use of electromagnets and a strainer-like filter to create a systematic process of extracting the plastics. The nonpolar properties of the oil attract plastic particles and prevent the suspension from dissolving in the polar water. Magnets were used to hold the fluid in place as it attracted and contained the plastics. To increase the efficacy of microplastics collected from water, homemade ferrofluids were synthesized, utilizing an acid based soap solution to lubricate the individual magnetite particles to synthesize a smoother suspension that could retain more plastic. On the other hand, commercial ferrofluids do not add a soap based component. Homemade ferrofluid was created by suspending magnetic fragments of iron oxide coated in oleic acid-based soap, in a non-polar homogenous solution such as oil.  In the process of creating magnetite, multiple slow titrations of ammonia were utilized to obtain optimal ferrofluid with strong magnetic properties. After the ferrofluid was synthesized, an experiment was conducted to test its efficacy against traditional ferrofluids. The commercial ferrofluid was found to have an overall efficacy of capturing around 88% of microplastics in water, while our ferrofluid captured approximately 91.02% of microplastics in water.  The ferrofluids created were especially effective against the three most common forms of microplastics: polyethylene, polypropylene, and polystyrene. With further research, this improved system has the potential of removing thousands of pounds of microplastics missed from current cleanup systems. 

During competition day, we presented our findings and were questioned by industry professional judges. By the end, we passed all stages of inspection before winning 1st place overall and receiving the "Water Research" award from 10 local water agencies. A select few teams including ours were promoted to compete in the California State Science and Engineering fair. Although Covid-19 prevented those plans from carrying through, I was honored and proud of the work we had put in to accomplish such feats!