The latest technology produced from fermentation waste

Jean Benoit Legault, The Canadian Press

MONTREAL – Researchers from the National Institute for Scientific Research (INRS) and the École de technologie supérieure have discovered that fermentation residues can be converted into ultra-small crystals that are used in advanced manufacturing technologies.

These crystals are called “quantum dots,” and they are actually “nanocrystals” each measuring a few billionths of a meter (a nanometer is a billionth of a meter).

These quantum dots are typically produced from heavy metals and pollutants such as cadmium and lead, and can alternatively be produced from spent grain, which is grain leftovers from breweries that in recent years have been reused in animal feed.

Quantum dots are used, among other things, to emit and absorb light, for example as sensors in biomedicine or as LEDs in next-generation displays. South Korean giant Samsung, in particular, is devoting massive resources to installing quantum dots for use in its phones.

Professor Federico Rosi, of INRS, explained.

It can be electricity, as it can be used to break down water molecules and separate hydrogen from oxygen. Then the hydrogen can be used as a clean fuel.”

Professor Rosie and colleagues presented this spring in the journal’s pages RSC . advance From the Royal Society of Chemistry, it is possible to produce carbon quantity points by the means available.

They used a home microwave oven to char the spent beans, creating a black powder that was then mixed with distilled water and returned to the microwave. Passing through centrifuges and advanced filtration steps made it possible to obtain quantum dots.

The final product is capable of detecting and quantifying heavy metals, as well as other pollutants that affect water quality, the environment and health.

“We can modify the properties of quantum dots by changing their size, morphology and composition,” Professor Rosie said.

He goes on to say that the quantum dots that show the best performance unfortunately contain heavy metals whose use is not desirable from an environmental point of view. So we sought to replace it with non-toxic and, ideally, very plentiful items.

The drawing contains elements such as carbon, nitrogen and phosphorous that will contribute to the efficiency of the obtained quantum dots. Previous work has shown that quantum dots obtained from carbon are interesting for capturing sunlight and converting it into another form of energy.

This project was completed thanks to the cooperation of the micro-brewery Brasseur de Montréal, which contributed grain residues. The researchers are now not ruling out contacting a larger brewery that might be interested in this technological breakthrough.

“The basic principle is to try to recover the waste,” Professor Rosie said.

But good. From there to the conclusion that the more beer drunk, the more it helps our hospitals to equip themselves with the latest equipment they need, there is certainly a step we must be careful not to overstep.