Remove oil from water via nanoparticles and magnet

Methods for uprooting oil from water are usually challenging, costly and environmentally hazardous but, researchers have recently discovered an enhanced technique that can remove oil and clean water.

Researchers from The University of Texas, publishing their findings in the Journal of Nanoparticle Research, made use of a process based on electrostatic force and a magnet in which magnetic nanoparticles are used for separating oil from water.

Researchers strongly deem their new procedure to advance water treatments for oil and gas production along with proficiently cleaning up oil spills and conceivably removing lead from drinking water.

Nanoparticles are little particles used for coating various chemicals like polymers. They are also used in the fields of medicine, electronics and energy. Their flexibility made the team to inquire more about them and they think their method could also be used for treating millions of gallons of fresh water.

According to Phys.org, the existing methods are able to separate 95% of oil but still leave behind tiny droplets of oil that are hard to extract, this in turn makes the treatment of water more challenging and perilous.

The lead author of the study, Saebom Ko claimed, “This new technique is really aimed at removing that little bit of oil in that water that needs to be removed before you can consider it treated. The advantage of employing magnetic nanoparticles is that the small oil droplets that attach to the nanoparticles are much more quickly separated from water than traditional physical separation processes because magnetic force can be orders of magnitude larger than gravitation.”

Ko and his team devised surface coatings for magnetic nanoparticles for removal of oil. They used a system known as high gradient magnetic separation – a process used during mining and food industries for removal of metals and toxic particles respectively.

The surface coatings for nanoparticles stick to oil droplets through electrostatic force. The magnetic nanoparticles were covered with polymers whose surface charge is positive. The positively charged particles then bolt up negatively charged droplets of oil by electrostatic attractive force. This process takes up seconds in laboratory and can also be performed in reverse.

“It's a simple idea. We are leveraging the magnetic properties of these nanoparticles to get them to stick to the oil droplets and essentially magnetize the oil droplets so they can be pulled out with a magnet,” Hugh Daigle, the co author said.

The effectiveness of the process has inspired the researchers to think about different applications. They also envisage designing a technique for using these particles to clean oil spills from oceans and remove lead from drinking water. Science Daily quoted Daigle saying, “The applications can extend far beyond the oil field because, with an appropriate surface coating design, you can take your magnetic core and coat it with whatever chemical you choose on the outside to stick to the target and pull it out with a magnet.”