Supercritical fluid research the focus of international collaboration

Edmonton, AB – Food engineer Feral Temelli, a researcher in the University of Alberta’s Faculty of Agricultural, Life and Environmental Sciences and the co-inventor of a novel drying technology for biopolymers using supercritical carbon dioxide, is leading a U of A team that recently signed a memorandum of understanding with Innovation Fluides Supercritiques (IFS).

IFS is a non-profit organization based in France that promotes the advancement of supercritical fluid technology globally. It already has partnerships with scientists in Japan, another country at the forefront of the field, said Temelli.

Supercritical fluids have properties similar to those of both a liquid and a gas. They only form when temperature and pressure are increased to levels above the critical point of that substance. They are as dense but not as viscous as a liquid, so they flow and diffuse faster, and can be manipulated in many ways.

“So, I can take CO₂, for example, use it as an extraction solvent and replace some of the petroleum-based solvents that are used in the processing of various agricultural products,” she said. “And the real beauty is, after we do an extraction we can release the pressure and CO₂ becomes a gas—which is not a solvent anymore—and get a ‘natural’ extract with no solvent residue left behind.”

By contrast, traditional petroleum-based methods require additional costly treatments to remove the solvent.

One of the first commercial uses of supercritical fluids was decaffeination of coffee. Now, the technology is used in an array of industrial applications in food, cosmetics, pharmaceutics, materials, chemistry, energy and waste treatment.

In her supercritical fluid research, Temelli will continue to focus on the use of CO₂ for value-added processing of crops. Two other U of A scientists in the partnership—Marleny Aranda Saldana, an associate professor of bio/food engineering processing, and Selma Guigard, an associate professor of civil and environmental engineering—are studying food/biomass and oilsands-related applications, respectively.

Reported by Helen Metella, University of Alberta