Schulich team develops 'super sponge' for oil spill cleanup
Material outperforms current cleaning technology for aquatic spills
They call it “magnetic boron nitride (MBN)” but what a team of engineering researchers at the University of Calgary has developed, to put it simply, is a super sponge for soaking up aquatic oil spills.
Not only does the non-toxic biodegradable material, consisting of magnetic nanostructured white graphene, absorb crude oil at up to 53 times its own weight, it can also be reused over and over. And unlike traditional clean-up technologies, the groundbreaking nanomaterial allows for salvage of spilled oil.
“The current technologies for oil spill cleanup only focus on impact mitigation and ignore crude oil recovery,” explains Dr. Nashaat Nassar, PhD, an associate professor at the Schulich School of Engineering.
“There is a need for an innovative technology to generate a high-performance material that can be used to both clean water and recover crude oil for further use after a crude oil spill.”
Nassar’s team has published details of their success in the Industrial and Engineering Chemistry Research journal, and the paper follows a precursor study from earlier in 2018, in which the Nassar team showed MBN was non-toxic, a vital factor when using nanomaterials.
With environmental concerns steering decisions on oil recovery and transportation, developing a practical produced, highly-effective material for marine spills is both timely and essential, says Afif Hethnawi, a PhD student of Nassar’s team.
“An average of about five million tons of crude oil are transported across the seas around the world annually and there is a significant risk of spills from either mechanical failure or human error,” explains Hethnawi.
“Through the structural atomic engineering of MBN, with its innovative features and our understanding of the mechanism involved in crude oil sorption, we are targeting to improve the technology used in crude oil spill recovery," adds Dr. Gerardo Vitale, PhD, a research associate on Nassar’s team
Magnets proved properties
Tests on the material relied on magnets instead of physical tools to remove the MBN and oil from the water, to show the absorption was strictly the result of the nanostructured white graphene, and not crude sticking to scoops or other equipment.
Placed in water where an oil spill has taken place, the hydrophobic MBN repels water while attracting the oil, at which point the MBN surrounds and absorbs it.
“It’s a little bit like a hotdog bun wrapped around a hotdog,” explains Nassar.
Oil can be reused
Once the oil has been soaked up, magnets are lowered close to the surface of the water, lifting the magnetic MBN and oil together, where it can be separated and the MBN reused.
While magnetic nanomaterials have been considered before for oil spill cleanup, biopersistence – that is, a material tending to remain inside a biological host – made the prospect too dangerous, due to the risk of disease like lung cancer and genetic damage to the lung.
With MBN having been shown to be biocompatible with humans and other organisms, that hurdle has now been overcome. Nassar says the new nanomaterial is ready for real-life applications in protecting the environment, and helping safeguard oil transport over water.
“If someone wants to start manufacturing this, it is ready to be used right now,” he says.