Fluorine-Free Hybrid Surfactants for Fire-Fighting Foams

Aqueous film-forming foams (AFFFs) are among the most popular fire-fighting foams used against fuel and oil fires because of their effectiveness and their ease of application. Unfortunately, recent studies have shown that certain fluorosurfactants used in AFFFs are toxic to aquatic life and tend to accumulate in the blood of animals and humans. The manufacturer recently has phased out these surfactants. Current AFFF concentrates contain fluorosurfactants that are chemically different from those that have been phased out. However, the toxicity and persistency in the environment of these fluorosurfactants are unknown and are under investigation by the U.S. Environmental Protection Agency and the Fire Fighting Foam Coalition, a group that represents AFFFs and fluorosurfactant manufacturers. Thus, their future presence in the market is unsure. Therefore, the fire-fighting industry needs new environmentally friendly foaming agents and foam stabilizers that will replace fluorosurfactants in fire-fighting foams. The goal of this research project is to develop a new, fluorine-free fire-fighting foam based on TDA Research, Inc.'s (TDA) proprietary additives. During Phase I, TDA began developing novel fluorine-free foam stabilizers for fire-fighting foam concentrates. It was shown that TDA foams are up to 60 times more stable than current AFFFs, and that the foam stability can be finely tuned over a wide range by properly selecting the chemistry of the additives and the composition of the solutions. TDA demonstrated that additives can be formulated into a concentrate that can be used with commercial fire-fighting equipment, and that TDA's foams can be used to extinguish hydrocarbon fires. TDA also identified new surfactant types that, in combination with TDA's foam stabilizers, offer the potential to make effective fluorine-free AFFFs. During the course of the Phase I project, contacts were beginning to be established with representatives of the fire-fighting industry, and many of them expressed an interest in this research and in the promising preliminary results. During Phase II, TDA will continue to work toward the optimization and commercialization of fluorine-free foam concentrates in collaboration with commercial partners. TDA also will evaluate the toxicity and biodegradability of the resulting product and its compliance with fire-fighting standards and environmental regulations.