Researchers at the Center for Environmental NanoScience & Risk (CENR) at the University of South Carolina’s Arnold School of Public Health are transforming the way we clean up large bodies of water after major oil spills or oil contamination from other wastes. Directed by Dr. Jamie Lead, professor of environmental nanoscience and risk and SmartState Endowed Chair for CENR, the team has developed a cheap and easy method for making nanomaterials that can be used to remove oil from oil-water mixtures.
Existing approaches to oil spill cleanups involve expensive and time-consuming methods that can be inefficient and ineffective. According to the Environmental Protection Agency, containment and recovery methods, such as barriers and skimmers to capture and store the spillage, serve as the primary line of defense against oil spills in the U.S. Cleanup techniques and biological and chemical methods can be used in conjunction with containment and recovery tactics. However, these processes have their own limitations, such as toxic residues that result from the chemical reactions.
These challenges and the environmental concerns these methods present have inspired scientists to turn to oil-absorbing, smart nanomaterials for solutions. “The Center’s new technique simply uses a polymer bound to a magnetic nanoparticle,” explains Dr. Lead. “The oil binds to the polymer and a magnet is then used to pull the polymer — along with the attached oil — out of the mixture, leaving only the water behind.” When applying this procedure in the CENR lab, the researchers simulated environmental conditions with oil concentrations that are the same or higher than the concentrations generally found when an oil spill occurs.
Developing the basic technique, published in Environmental Science and Technology and co-authored by CENR postdoctoral student Dr. Soubantika Palchoudhury, is only step one of their research. The next phase, which is nearing completion, employs a hydrothermal method (i.e., just water) rather than organic solvents at high temperatures to eliminate the possibility of toxic materials being released back into the environment. “We are also reducing the amount of time it takes to separate the oil and water from 12 hours to less than one hour,” says Dr. Lead. This second phase incorporates additional environmentally relevant conditions, such as the naturally occurring salts and organic materials found in large bodies of water, to further test the technique.
The third phase involves simplifying the procedure even further to make it less expensive, enabling the practical use of the method in the environment during discharges or spills. At that point in the CENR team’s research, this promising new technique could very well change the way we clean up future oil spills.