By Peter Weiss
“We thought nothing sticks to Teflon,” says chemist John A. Gladysz of the University of Erlangen in Germany. “Au contraire!” In an accidental discovery, his graduate student Long V. Dinh found that certain expensive chemical catalysts glom onto Teflon tape, providing a convenient way to recover them from solutions.
Gladysz and his colleagues study a new class of catalysts that, as Teflon does, contain many fluorine atoms. Suitable for most catalyzable industrial reactions, the compounds are not yet widely used, Gladysz says. In earlier work, his team engineered the fluorine-rich catalysts to precipitate out of cooled solutions, thereby making them easier to collect after use.
When Dinh added some ordinary Teflon tape to a solution as a mechanical aid for removing the precipitant—much as peanut shells on a bar floor catch debris when the bartender sweeps up—he was startled to observe that the catalyst had coated the tape. In an upcoming Angewandte Chemie, Dinh and Gladysz describe using Teflon tape to trap and release that and a related catalyst in a variety of reactions.
Gladysz attributes the phenomenon to chemical similarities between the catalyst and the Teflon. Chemical companies might someday use Teflon-coated equipment to take advantage of this new catalyst-recovering strategy on a large scale, Gladysz speculates.