The Magnetic Net: A Multi-Phase Approach to the Remediation of Oil and Microplastics

Hello , My name is Naina Patel from Sarnia, Ontario. Living in 'Chemical Valley' , I see how industrial outfalls threaten our Great Lakes. Research shows by 2050 , plastic could outweigh fish in our oceans.

I used ferrofluid , a non-polar liquid made of magnetite (Fe3o4) nanoparticles suspended in oil. These nanoparticles are superparamagnetic , which means they only become magnetic when a magnet is nearby. The secret to this process I call the 'Hydrophobic Handshake'. Oil , microplastics and ferrofluid are non-polar so they naturally want to stick together instead of mixing with water. (Hydrophobic Effect)

Ferrofluid's nanoparticles form a thin magnetic net around pollutants and it create a magnetic handle. This allows me to use high-strength Neodymium magnets to pull the entire pollutant-ferrofluid cluster out of the water.

My method allows me to pull even heavy 'Sinkers ' like PVC that traditional methods miss. In my 96 trials , I achieved 80-90 % removal efficiency for oil and microplastics. I use microscope and Image J software to verify my results.

To scale it up ,I created 3D prototype of 'Magnetic Gate' to remove pollutants at the source.

In summary , my project proves we can protect our Great Lakes with circular economy solution. Thank you.

Inspiration & Local Context (Image 1)

When I visited a health museum in Texas, I realized how seriously microplastics and oil can damage water. I learned that by 2050, the oceans could contain more plastic than fish by weight1. Growing up in Sarnia, I saw how industrial accidents can threaten the Great Lakes 2.

To understand why this is a systemic crisis, I analyzed global pollution pathways. My research shows that Land-Based Runoff (40%) and Wastewater & Microplastics (35%) are the primary sources of contamination, while Industrial Discharge (15%) and Accidental Spills (10%) complete the breakdown. This confirms that the real threat isn’t just large debris; it’s the continuous, invisible flow of pollutants into our water3 .

The Problem (Image 2)

Traditional remediation methods often fail to remove oil and microplastics simultaneously4. Many microplastics are hydrophobic, allowing them to interact strongly with oily pollutants5. Some heavy microplastics sink into benthic environments and carry contaminants through the ecosystem 6.

Question & Hypothesis (Image 3 and 4)

Inspired by NASA and magnetic-fluid concepts, I investigated ferrofluid as a magnetic glue for pollutant removal. I hypothesized that a 1.5 mL dose would form a larger “Magnetic Net” and remove more pollutants from water 7.

Human & Environmental Benefit (Image 5)

I am now working toward a scalable “Magnetic Gate” for industrial outfalls and sewage lines. This filter-free approach could help stop contaminants before they enter the food web and protect the Great Lakes.

Scientific Basis

To build a national-level solution, I combined NASA’s 1960s magnetic-fluid concept with modern chemistry. I investigated the “Hydrophobic Handshake”—a coined term for the strong hydrophobic interaction that allows oil, microplastics, and ferrofluid to cluster together in water and be removed with a magnet. This principle forms the core idea of my “Magnetic Net” method. [Image 1]

Experimental Design (Phase 1)

To ensure reliability, I completed 96 trials (4 ferrofluid doses × 2 oil types × 6 plastics). Each day I tested one pollutant. I used mineral oil and 5W30 motor oil, plus six plastics: PET (muffin boxes), HDPE (bottle caps), PVC (pipes), LDPE (squeeze bottles), PP (cups), and PS (lids). My goal was to test methods that can capture both low-density “floaters,” often missed by cleanup, and high-density “sinkers” such as PVC (about 1.40 g/cm³), which are commonly overlooked.

Protocol (Image 2)

I followed a strict 3-step procedure:

Setup: Add 15 mL of water with 20 microplastic pieces or 2.5 mL of oil.

Dose and mix: Add one of four ferrofluid doses (0, 0.5, 1.0, or 1.5 mL) and mix for 3 seconds.

Extraction: Use a high-strength neodymium magnet inside a protective sleeve for 10 seconds to remove magnetic clusters.

Efficiency Calculation

Oil Efficiency =  [(2.5 mL − remaining oil) ÷ 2.5 mL] × 100.

Microplastic Efficiency = [(20 − pieces left) ÷ 20] × 100.

Digital Validation (Image 3)

When ferrofluid interfered with visual counting, I learned to use microscope and image J software. Using a fixed scale and the Polygon Tool, I measured the total area before and after extraction. (Image 4)

Efficiency = [(Area before − Area after) ÷ Area before] × 100.

Scalability

I created a 3D “Magnetic Gate” prototype (Image 5) to show how this method can scale from a laboratory beaker to an industrial outfall pipe.

Project Overview & Main Finding

This project investigated whether ferrofluid can be used as a magnetic tool to remove oil and microplastics from water. A total of 96 controlled trials were conducted under standardized conditions. A clear dose–response relationship was observed between ferrofluid volume and removal efficiency. The 1.5 mL dose was identified as the optimal “tipping point,” consistently achieving 80–90% removal of pollutants.

Comparison of Ferrofluid Doses

At 0.0 mL (Control), no oil or microplastic removal occurred, confirming pollutants do not naturally separate from water without intervention.

The 0.5 mL dose showed limited effectiveness, mainly removing floating or surface‑level pollution and leaving many microplastics and sinking plastics behind.

In contrast, the 1.5 mL dose formed a strong “magnetic net” that consistently captured both oil and microplastics across all tests. This dose produced the highest removal efficiencies.

Oil Removal Effectiveness (Image 1)

The magnetic net was effective at removing oil across different viscosities. Results showed approximately 81% removal of mineral oil and approximately 81% removal of motor oil, indicating the method works well for both low‑ and higher‑viscosity oils.

“Sinker” Breakthrough Discovery (Image 2)

A key finding involved high‑density “sinkers” such as PVC (1.40 g/cm³). At a 0.5 mL dose, LDPE (0.92 g/cm³), a low‑density floater, was removed at about 40% efficiency, while PVC sank and was removed at only 30% efficiency. When the ferrofluid dose increased to 1.5 mL, PVC removal efficiency rose to 85%. The ferrofluid coated the submerged plastics and created a magnetic handle, allowing the magnet to lift them against gravity and bring them to the surface. This shows that higher doses can capture dense plastics normally missed by traditional cleanup methods.

Data Reliability & Analysis (Image 3)

Each condition was tested three times, and results were averaged to reduce random error and improve reliability. When ferrofluid staining made manual counting difficult, ImageJ digital analysis was used. Pollutant surface area (in mm²) was measured under magnification using a fixed scale and the Polygon Tool. Digital and manual removal estimates closely matched, confirming the accuracy of the analysis and consistency across trials.

Unexpected Result: Magnetic Flocculation (Image 4)

An unexpected but important observation was magnetic flocculation (clumping). Instead of coating individual particles, the ferrofluid acted like magnetic glue, causing small plastic pieces and oil droplets to stick together into larger clusters. These larger aggregates were easier for the magnet to capture, which increased overall removal efficiency. This effect helps explain the sharp rise in performance at higher ferrofluid doses and supports the idea of a “Magnetic Net” pulling many pollutants out at once.

Practical Application (Image 5)

Results were used to design the Magnetic Gate prototype. The system is intended for industrial outfall pipes, where oil and plastics can be magnetized and captured before entering freshwater ecosystems such as the Great Lakes. This approach offers a filter‑free, tunable method to intercept pollutants at the source.

Key Conclusions

Experiments identify a 1.5 mL ferrofluid dosage as the optimal “tipping point,” consistently achieving >85% removal of oil and microplastics.

Nanotechnology provides a functional “magnetic handle” for high-density PVC “sinkers” (1.40 g/cm³), which traditional surface-skimming methods typically fail to collect [Image 1].

These results prove the system is highly efficient, repeatable, and scalable.

What I Learned

The “hydrophobic handshake,” enhanced by magnetic flocculation, causes non-polar pollutants to aggregate into clusters rather than remaining as individual particles [Image 2].

This conversion of dispersed waste into harvestable magnetic clusters makes mass remediation feasible.

Digital validation using ImageJ provided the quantitative precision necessary to confirm that visual improvements in water clarity translated to high removal efficiency.

Why This Matters

A point-source “Magnetic Gate” could intercept pollutants at industrial outfalls before they disperse into the St. Clair River and the Great Lakes [Image 3].

Beyond efficiency, a circular resource model suggests that recovering and reusing ferrofluid could significantly lower operational costs, improving real-world economic feasibility [Image 4].

Because the system functions in a closed recovery loop, it minimizes secondary environmental risks while maximizing pollutant capture [Image 5].

Ultimately, this research proves that molecular-level design can overcome the core limitations of existing environmental remediation technologies, offering a scalable path forward for protecting our freshwater ecosystems.

Accuracy Improvements

Implement automated mechanical mixing to ensure consistent sample preparation across all trials.

Incorporate advanced spectroscopic methods and automated particle detection to measure microscopic contaminants with higher precision [Image 1].

Next Steps

Develop the “Magnetic Gate” into an adaptable system to capture pollutants directly at industrial sources [Image 2].

Evaluate removal efficiency under varied flow rates in tank-based simulations [Image 3].

Validate bio-based ferrofluids to ensure zero aquatic toxicity and test saltwater performance for global deployment [Image 4].

Scalability & Sustainability

Quantify long-term effectiveness and economic viability using rigorous recovery efficiency metrics and lifecycle analysis [Image 5].

I am deeply grateful to those who supported this project. Your guidance was essential in refining my experimental protocol and analyzing results at the laboratory scale.

The Health Museum (Texas): Your insightful exhibits on microplastic pollution first inspired my interest in this global challenge.

Lambton County Science Fair: Thank you for providing an inspiring platform that encourages young scientists to innovate and share ideas within our community.

My Parents: Thank you for your constant encouragement, guidance, and the resources you provided throughout every stage of this project.

World Economic Forum. (2016, January 18). More plastic than fish in the ocean by 2050: Report offers blueprint for change. https://www.weforum.org/press/2016/01/more-plastic-than-fish-in-the-ocean-by-2050-report-offers-blueprint-for-change/

CBC News. (2025, February 25). Suncor spill in Sarnia. https://www.cbc.ca/news/canada/windsor/sarnia-suncor-spill-1.7495314

National Academies of Sciences, Engineering, and Medicine, 2022 https://www.nationalacademies.org/news/land-based-runoff-remains-top-source-of-oil-in-the-ocean-says-new-report

He, P., et al. (2022). Removing microplastics from aquatic environments: A critical review. Environmental Science and Pollution Research, 29, 69345–69365. https://pmc.ncbi.nlm.nih.gov/articles/PMC9722483/

Goswami, L., et al. (2017). Interaction of hydrophobic polymers with model lipid bilayers. Scientific Reports, 7(1), 5897. https://doi.org/10.1038/s41598-017-06668-0

Gledhill, M., et al. (2025). Direct evidence that microplastics are transported to the deep sea by turbidity currents. Environmental Science & Technology, 59(15), 1240–1252. https://doi.org/10.1021/acs.est.4c12007

Pang, H., et al. (2024). Amphiphilic magnetic particles dispersed in water and oil for the removal of microplastics. ACS Applied Materials & Interfaces, 16(15), 19572–19584. https://doi.org/10.1021/acsami.3c19398

Image: https://education.nationalgeographic.org/resource/marine-pollution/