Using Magnets to Clean Up Oil Spills

MIT researchers have developed a new technique that could be used to help clean up oil spills. The technology would be an add-on to devices such as skimmers, which only have an oil-recovery efficiency of about 50%. The technique involves mixing water-repellent ferrous nanoparticles with the oil, which could then be separated from the water using magnets. The researchers envision that the process would take place aboard an oil-recovery vessel, to prevent the nanoparticles from contaminating the environment. Afterward, the nanoparticles could be magnetically removed from the oil and reused.

Transcript

00:00:00 [MUSIC PLAYING] My name is Marcus Zahn. I'm a professor of electrical engineering at MIT. And one of my primary research areas relates to the theory and applications of magnetic liquids, synthesized fluid, a fluid that when stressed by a magnet, tends to create interesting hydrodynamic phenomenon. Magnetic fluids are a synthesized fluid composed of 10-nanometre magnetic nanoparticles coated

00:00:31 with a surfactant to stabilize it within a host liquid. Typically, such fluids are water-based or oil-based. After the BP oil disaster about two years ago in the Gulf of Mexico, I got the idea that if the oil were magnetic, we would be able to remove it with strong magnets and separate it from the water. When oil spills occur, a lot of the oil sinks. And then, most of the oil spill technology deals with the oil that's floating on top, and it really spreads far and wide.

00:01:01 The current oil spill technology, like skimmers-- they're very good in calm waters. But in choppy waters, their oil recovery efficiency is about 50%. So whatever they recover from the seawater would be half oil, half water. And our technology is supposed to improve that efficiency. It's going to be an add-on to that efficiency. And what ours would do is collect that 50% of oil or water in a confined space,

00:01:29 and then you'd put magnetic nanoparticles that like the oil. So it makes the oil magnetic. And then you would separate the magnetic oil from the water face. So you get clean water, and then you get the magnetic coil. And then you, using existing technology, can actually remove the magnetic nanoparticles from the oil and send the oil to a refinery, or you can recover the oil. When an oil spill occurs, it's actually easier

00:01:57 to burn the oil because it's just spread so far. But it's a big environmental disaster already, and then you're burning it. Another thing they do is they collect the oil and water. And they collect in these big tanks, and they let it settle due to density differences. But that takes a long time. What ours does is-- because of magnetic forces, you can separate the two very quickly because the forces are so much stronger than density.

00:02:22 And that's the advantage. You can actually process this much faster and continuously without any real power being expended.