From crisp packets to high-quality plastic: Ghent tests new recycling route

Researchers at Ghent University are using dissolution to recover high-quality plastic from difficult waste streams. Examples include crisp packets and colourful detergent packaging.

Dissolution is an advanced recycling technique that sits between mechanical and chemical recycling. In conventional mechanical recycling, plastic waste is sorted, washed, shredded and melted into a new raw material. However, heavily contaminated or mixed plastics can lose quality through this process.

Chemical recycling, meanwhile, breaks down the polymers themselves. Processes such as pyrolysis can use high temperatures to turn plastic waste back into oil, while other methods reduce polymers to smaller molecules or monomers.

Ghent University’s Clarify pilot installation, costing more than EUR 2 million, uses solvents to separate polymers from contaminants including inks, colourants, plasticisers and stabilisers.

The technology can also process multilayer films and other plastics made from several components. Following purification, the recovered polymers can be used to produce new high-quality plastics, including material for food-grade packaging.

Pilot-scale testing

The Clarify project started earlier this year at the Kortrijk campus. The installation is intended to help bridge the gap between laboratory research and industrial-scale application.

Steven De Meester of Ghent University’s Department of Green Chemistry and Technology has researched dissolution since 2018. He describes it as a relatively simple process with low energy consumption and a recovery yield of more than 90%.

‘Everyone thought for a long time that chemical recycling would solve everything. Now I notice that there is more recognition for dissolution,’ De Meester says.

Dissolution does not break down the polymers. Instead, a solvent selectively dissolves the target polymer and allows it to be separated from other materials. The recovered polymer can then be processed into new products.

Port connection

Ghent University has established a new chair for dissolution funded by the province of Zeeland and Dutch company PS Loop in Terneuzen.

PS Loop is among the larger European companies already applying dissolution technology. The partnership also reflects the university’s proximity to North Sea Port, which connects Ghent, Terneuzen and Vlissingen.

Several companies in the port area are following developments in the technology, while the university’s research team continues to work on the remaining technical challenges.