About This Project

Ask the Scientists

What is the context of this research?

Each year, more than 100,000 metric tons of oil or refined petroleum product worldwide are released into the sea due to spills. Large releases such as the Deepwater Horizon/Macondo Well oil spill in 2010, which resulted in the release of more than 4 million barrels of oil, pose an acute risk to the surrounding ecosystem, especially nearby coastal areas. Chemical dispersants, which are mixtures of soap-like organic chemicals (called 'surfactants') and solvent, are valuable tools for marine oil spill response. The surfactants facilitate the breakdown of the oil into droplets, so that they can be washed away. The solvent helps the surfactants penetrate the oil layer. 2.1 million gallons of chemical dispersants were applied in response to the Deepwater Horizon/Macondo Well oil spill. Synthetic chemical dispersants are expensive. Many are also harmful to marine and coastal flora and fauna, and exposure also can be harmful to the health of workers.

What is the significance of this project?

We propose that natural surfactants, when combined with slow-evaporating solvents, may provide effective, economical alternatives to chemical dispersants. These alternative dispersants may also be less harmful to workers and the marine ecosystem.

What are the goals of the project?

Our experiments will test the following hypothesis: Naturally occurring surfactants reduce the interfacial tension between oil and seawater, thereby promoting the formation of small oil droplets.

• The effect of the surfactant on the oil/seawater interfacial tension will be characterized in our laboratory.
• The effects of different carrier solvents, dilution, and agitation on the oil droplet size distribution and droplet formation dynamics will also be tested.
• Environmental factors such as water salinity, temperature, and pH will be varied in order to assess the efficacy of the surfactant under a range of realistic conditions.