Nanoparticle recycling may clear cost hurdle to commercialisation

An innovative way to recycle costly nanoparticles could accelerate the application of the technology across a vast range of sectors, including food packaging, said new research.

A team from the University of Bristol, UK, said its breakthrough method could make it easier for manufacturers to “recover, recycle, and reuse nanoparticles, some of which ounce for ounce can be more precious than gold”.

Professor Julian Eastoe said the development of a special type of microemulsion that separates nanoparticles has the potential to make use of the technology more affordable and serve as a vital driver in boosting commercialisation.

“Nanotechnology has made great advances and holds much promise,” he said. “However, for various reasons few commercial applications have yet come to market. Some reasons for this are significant hurdles to generate, recover and reuse nanometre-sized particles, especially those expensive materials such as gold and palladium.”

In a study published in bi-weekly journal ACS' Langmuir, Eastoe et al outline how they developed the microemulsion – a mixture of oil and water – that could solve the problem. In lab tests involving cadmium and zinc nanoparticles, they demonstrated how the oil and water in the microemulsion separated into two layers when heated. One layer contained nanoparticles that could be recovered and the other contained none. The separation process is reversible and the recovered particles retain their shape and chemical properties, which is crucial for their reuse, the study said.

“This is a surprisingly simple process that relies on an understanding of what makes particles stable in the first place, and then finding what makes them unstable,” added Eastoe.

Nanoparticle recoveries from this technology are documented currently at about 70-80 per cent - with unpublished results with water-based nanomaterials showing 99 per cent recoveries at the first recycle, Eastoe told FoodProductionDaily.com. The team forecasts that the method could be use to recycle nanoparticles up to ten times.

Packaging application

The research could have an application for the packaging industry - particularly smart packaging, he said.

The challenge would be to release the nanoparticles from the polymer or film, and transform it into a solution. He said the development of such a method was “feasible” and could have widespread cost implications fro the development of nanotech in the packaging industry.

Scaling up

The team said it is interested in partnering with industry representatives in order to explore scaling up the process.

“Given the right backing, we believe the process could become commercially viable within a year,” Eastoe said.