WEST LAFAYETTE, Ind. - Let a bunch of fluorine atoms get together in the molecules of a chemical compound, and they're like a heavy metal band at a chamber music festival. They tend to dominate the proceedings and not always for the better.
That's particularly true where the global warming potential of the chemicals is concerned, says a new study by NASA and Purdue University researchers.
The study offers at least a partial recipe that industrial chemists could use in developing alternatives with less global warming potential than materials commonly used today. The study was published in the Proceedings of the National Academy of Sciences.
"What we're hoping is that these additional requirements for minimizing global warming will be used by industry as design constraints for making materials that have, perhaps, the most green chemistry," says Joseph Francisco, a Purdue chemistry and earth and atmospheric sciences professor.
The classes of chemicals examined in the study are widely used in air conditioning and the manufacturing of electronics, appliances and carpets. Other uses range from applications as a blood substitute to tracking leaks in natural gas lines.
The chemicals include fluorine atom-containing compounds such as hydro fluorocarbons, per fluorocarbons, hydrofluoroethers, hydrofluoroolefins, and sulfur and nitrogen fluorides.
In a 2009 study, Francisco and NASA collaborators Timothy Lee and Partha Bera examined the molecular qualities that make fluorinated compounds even more powerful warming promoters than chemicals emitted in greater quantities, such as carbon dioxide and methane.
The fluorinated compounds proved to be far more efficient at blocking radiation -- or heat -- in the atmospheric window. The atmospheric window is the frequency range in the infrared region of the electromagnetic spectrum through which radiation from Earth is released into space. This helps cool the pla
|Contact: Greg Kline|