Dissolution: a fountain of youth

Polystyrene back in the spotlight

The French oil group Total has set itself the challenge of producing 30% of its polymers from high-quality recycled materials by 2030. To achieve this, it has teamed up with American company PureCycle Technologies, the inventor of a process capable of recycling polypropylene by dissolving it. The aim is to give this recycled material the same characteristics as virgin resin, which would enable it to be used in food packaging.

Total is also interested in recycling polystyrene using the same type of technology. The group has already begun various test phases to recycle various polystyrene objects, such as yoghurt pots, household appliance components and insulation. A significant proportion of the polystyrene produced is used to make yoghurt pots and food trays, so the group has joined forces with various partners, including dairy products manufacturer Yoplait (General Mills) and Portugal's Intraplas, a company with expertise in the extrusion of plastic sheets for the food industry. After several months of trials, the consortium succeeded in developing a chemically-recycled polystyrene (rPS) with qualities identical to those of virgin polystyrene. "This initiative is a major step forward in building a circular polystyrene economy in France with the entire value chain and contributes to achieving our ambition of achieving 100% recyclable or re-usable packaging by 2025," said Frédéric Chapuis, Yoplait's sustainable packaging strategy manager.

Many yoghurt pots are made of polystyrene. Recycling them into new yoghurt pots is one of the major challenges of chemical recycling.

Polyamide reinvents itself

Airbag manufacturing generates approximately 25,000 tonnes per year of polyamide-based technical fabric waste. To this must be added 100,000 tonnes of end-of-life airbags. Until now, these cushions made of a mixture of silicone and polyamide could not be recycled because it was almost impossible to separate the two components. Polyamide producer Domo Chemicals has a process that combines very fine grinding and dissolving to get back the original polyamide. Called technyl®4earth®, this process enables Domo to offer a high-quality recycled polyamide (PA6.6) for the automotive, construction, household appliances and leisure industries. A life cycle analysis carried out on these recycled polymers showed a 26% reduction in the carbon footprint, a 60% reduction in non-renewable resources and a 70% reduction in water consumption compared to the conventional process. This innovation is being closely monitored by the automotive industry and its equipment manufacturers, who aim to introduce 20% of recycled materials in their upcoming models.

Polyloop, the clever and practical solution

World-famous for its flexible composite materials, most often PVC-based, the Serge Ferrari company has been involved in recycling its products for more than ten years. As early as 2008, the canvas manufacturer took part in the Texyloop initiative, a dissolution recycling technology which makes it possible to separate PVC from polyester, among other things. Based in Italy, the Vinyloop production site has made it possible to recycle more than 13 million square metres of material in about ten years. Thanks to this technology, the material has found a second life in the form of insulation films for landscape terraces and various other types of membranes.

On the strength of this experience, Serge Ferrari launched the Polyloop project more than a year ago using a rather similar dissolution technology. End-of-life composite fabrics are crushed and then placed in a solvent. Only the PVC is dissolved. All that remains is to filter the liquid obtained and to separate the solvent from the polymer through the process of evaporation to recover virgin PVC.

The aim is now to develop mini-units for chemical recycling. Installed in an easy-to-use container, one unit can regenerate 300 kg of composite PVC in 3 hours. Perfectly adapted to the industry’s needs for the treatment of their post-industrial or post-consumer waste, this process does not require too much energy input. A good idea to further reduce the waste transport carbon footprint. Serge Ferrari hopes to install the first modules next year.