Technological watch

Scientists from the Universities of Bath and Birmingham have developed a new way of chemically recycle plastics that converts plastics back into their constituent chemical molecules. Using this method recycled plastic can be used to make new plastics of the same quality as the original.
New Process for Recycling Plastics
The team’s method uses lower temperatures and more environmentally-friendly catalysts than previous methods.
The researchers recycled plant-based PLA, which is bio-based and is used in “biodegradable” food packaging and disposable cutlery and cups. PLA isn’t currently recycled because it’s not used widely yet, however with growing awareness of plastic pollution, the demand from consumers for recyclable packaging is growing.
Avoiding Quality Erosion of Plastics
Professor Matthew Jones, from the University of Bath, said, “Most plastic is currently recycled using mechanical methods, where they are chipped into granules and melted down before being molded into something new. "
“The problem is, melting plastic changes its properties, and reduces the quality, which limits the range of products in which it can be used.”
“Our method of chemical recycling overcomes this problem by breaking down plastic polymers into their chemical building blocks, so they can be used all over again to make virgin plastic without losing any properties.”
The team has also started the trial of a similar process for recycling PET, which is used for drinks bottles.
Plans for Up-scaling the Process
So far, the technology has only been demonstrated on a small scale, however collaborators at the University of Birmingham are now working to scale up the system to produce larger quantities of starting chemicals.
Circular Economy with Reducing, Reusing and Recycling
Dr Paul McKeown from the University of Bath, said, “PLA is being increasingly used and it doesn’t biodegrade with home composting, and isn’t currently recycled, so, at the moment it commonly ends up contributing to the tons of plastic waste in landfill and oceans."
“There is no single solution to the problem of plastic waste – the approach has to be a combination of reducing, reusing and recycling. Our method of chemical recycling could allow carbon to be recycled indefinitely - creating a circular economy rather than digging more up from the ground in the form of fossil fuels or releasing it into the atmosphere as a greenhouse gas.”