Photo-on-demand one-pot synthesis provides an environment in which harmless source materials such as the dry-cleaning agent perc can be upcycled to useful products safely, cheaply and in an environmentally friendly way. Credit: Akihiko Tsuda
Kobe University researchers have developed a sustainable method to upcycle the common dry cleaning solvent perc into useful chemicals. The method relies on closed environment synthesis utilizing UV activation and presents an opportunity to reduce the environmental impact of chemical synthesis.
Perchloroethylene, or perc, is considered non-harmful and is widely produced and used throughout the world as a solvent and degreaser. In the study, published in The Journal of Organic Chemistry, the researchers outlined a novel method to synthesize carbonate esters and chloroform from perc utilizing UV light. Additionally, this synthesis is carried out without the need to directly handle toxic materials such as phosgene.
"Because perc is nonflammable and stable enough to be used as a solvent, its use as a raw material for organic synthesis has received little attention. However, using our original photo-on-demand organic synthesis method, we have succeeded for the first time in simultaneously obtaining industrially important carbonates and chloroforms from that source," said Akihiko Tsuda - professor of chemistry at Kobe University.
To further reduce the environmental impact of the process, the researchers replaced conventional mercury lamps that emit high-energy ultraviolet light with LED lamps generating mild ultraviolet light. The change required slight modification of the process, but after optimization allowed for the synthesis of the desired products.
Tsuda believes the synthesis methods presented could reduce the environmental impacts of synthesizing desirable chemicals. "It is a safe, inexpensive, simple, and environmentally friendly chemical reaction. I expect that this new method of utilizing and upcycling perc, which is used in large quantities around the world, will be a significant step toward the realization of a carbon neutral and sustainable society."