Grant: Collaborative Research and Development Grants

Surfactants such as soaps and detergents are chemicals that stabilize oil/water mixtures called emulsions. Emulsions are often desirable in the energy industry during oil production, environmental cleanup, and other applications. However, after the emulsions are used, the emulsion must be ""broken"" or separated into its oil and water components. The surfactant that helped stabilize the emulsion then becomes a liability because it makes it hard to break the emulsion. The surfactant is also a liability because it will cause environmental problems once the water is discarded. These disadvantages could be eliminated by the design and implementation of switchable surfactants. A switchable surfactant can be reversibly converted into a molecule that is not a surfactant, upon application of some kind of trigger. In order for the surfactant to be truly switchable, the inactive form of the molecule must be convertible back into the surface-active form by the application of another trigger or removal of the first trigger. The proposed work will explore switchable surfactants as a new approach to surfactant design that should facilitate emulsion breaking. The work will emphasize applications in the energy industry. Most importantly, the switchable surfactants will use inexpensive and safe reagents to trigger the switching of the surfactant; these triggers will be air and recycled CO2. In contrast, the cleavable and switchable surfactants in the literature require acids, bases, ozone, or irradiation.