Recycling plastics through dissolution

The different ways of recycling plastic

What is the best, sustainable solution for waste management and recycling? Companies initially choose to recycle plastic into plastic, i.e. mechanically recycling.

But what if mechanical recycling is not possible because the quality of the plastic waste stream is inadequate? Or if the recycled plastic can only be used in low-value applications, also known as ‘downcycling’?

Other plastic recycling options include chemical recycling, which splits the various polymers into chemical components that companies can use to make new polymers. This process produces virgin-like plastic but consumes significant amounts of energy.

Between mechanical and chemical recycling there is physical recycling, which includes physical treatments such as dissolution.

What is dissolution?

Dissolution uses a solvent that will dissolve one polymer but not another, or the polymer but not the additives in the plastic. These polymers and additives can then be recovered and reused in an equivalent application.

The challenge is that the combination of plastics and additives always varies over the different waste streams. So in developing TNO Möbius dissolution technology, we are looking for new unique solvent-polymer combinations.

Recycling plastics into purified polymers

TNO Möbius dissolution technology is a physical recycling method developed to selectively dissolve certain polymers from a plastic mixture under superheated conditions. We then combine this dissolution technology with removal of impurities from the polymer solution. The purified polymer can then be recovered.

TNO Möbius technology involves the use of a low-boiling solvent at elevated temperature and pressure. This facilitates the dissolution of the polymers and allows recovery of the solvent.

Collaboration across the plastics value chain

So far, TNO Möbius technology has been developed and applied in national and European collaborative projects with research institutes and industrial partners, as well as in commercial projects for clients.

The larger projects often span the entire plastics value chain for end-of-life materials such as discarded electronics (PLAST2bCLEANED, Impres), automotive waste (ALMA, ABSoIEU) and (multilayer films) packaging (CIMPA, Syschemiq).

Collaboration with Braskem and ELIX Polymers

These projects then lead to collaborations with industry such as Braskem and ELIX Polymers.

We concluded a joint development agreement with Braskem to recycle polyolefins efficiently and environmentally friendly with use of the TNO Möbius Technology. Polyolefins are polymers that are build up from carbon and hydrogen only and can be processed into products such as plastic bags, packaging, film, pipes and fibres.

We also entered into a collaboration to recycle ABS polymers with ELIX Polymers, a leading European producer of ABS resins and derivatives.

ABS is a light but tough, impact-resistant polymer that is easy to injection mould. This polymer is used un durable products such as car bumpers and household appliances. Therefore, the ABS in waste streams is too degraded to be re-used in high-end products. TNO is further developing the TNO Möbius technology to rejuvenate the ABS and with this close the value chain.

Expertise in research for recycling technologies

TNO’s strength lies in the fact that many of these projects and collaborations leverage the knowledge and synergies of the various TNO expertise groups focused on areas such as:

• dissolution-based recycling
• characterization of polymer behavior
• mechanical recycling and redesign of plastic products
• chemical analysis of polymers
• systematic impact assessment of plastics value chains
• thermochemical recycling

Are you a new partner who can benefit from this technology?