"When used in jet fuel, (the new polymers) reduce the risk of explosion after impact; when used in diesel fuel, they reduce soot formation in the engine; and when added to fuel in pipelines, they reduce the pumping cost and increase the throughput," lead author Julia Kornfield, professor of chemical engineering at Caltech told reporters during a conference call.
The concept of developing such materials was first proposed in 1977, after a fatal runway collision between airplanes in Spain, which produced a fine mist of jet fuel, erupting in a fireball that claimed 583 lives.
"Although the accident occurred on the ground, only 61 people survived," Kornfield said. "It was a watershed moment that galvanized international efforts to reduce the risk of post-crash fires."
A six-year research program by U.S. and British researchers led to a fuel additive, called FM9, which was also comprised of ultralong polymers, but the effort ended in failure in 1984 as the chemical made fuel sticky and difficult to handle.
"Ultralong polymers were needed to control mist. But simply pumping the fuel caused the polymers to break into shorter segments, losing their efficacy," said Kornfield, who restarted the research in 2002.
With the help of her students, especially two from China, Ming-Hsin Wei and Boyu Li, Kornfield designed polymers that can form "strong but reversible links" with other polymers to produce ultralong polymers, which they call megasupramolecules.
In tests, these long polymers resulted in a significant reduction in misting and explosiveness, even after repeated passage through a fuel pump.
Furthermore, they are compatible with current engines and did not lead to a decrease in engine efficiency, they said.
The additives have other benefits as well. For example, a series of tests in 2014 using diesel engines showed they can reduce diesel soot while maintaining the engines`power and efficiency. They also can improve the flow of fuel through pipelines by reducing turbulent drag.
Kornfield said the additives might become commercially available in diesel fuel within two years but in terms of jet fuel, it is "a more lengthy" and involved process of approval from the U.S, Federal Aviation Administration that normally takes five to seven years.
She estimated that the additives would only add about six U.S. cents a gallon (3.78 liters) to the cost of fuel.
"I hope that the polymers we discovered will go on to save lives and reduce burn injuries," she said. "I hope they`ll improve safety and security on our roads and in the air."
More about:
