Covestro pilots chemicals recycling process to close loop on used mattress foam

COVESTRO has begun to pilot a chemical process to recycle the foam from used mattresses. If successful, the initiative will recover two key raw materials that will be used to produce fresh foams.

Around 30m mattresses are discarded in the EU each year, and according to data from the trade body EUROPUR around 90% of the mattresses produced in the EU each year contain 2–15 kg of polyurethane foam. A key challenge with recovering polyurethane from used mattresses is that it decomposes at elevated temperatures so cannot be melted to make new products as is common with other recycled plastics.

Covestro is developing a chemical recycling process to recover two raw materials used to produce polyurethane foam: polyol and toluene diamine (TDA), which is the precursor to toluene diisocyanate (TDI). It has begun operating a pilot plant to recover polyols at its site in Leverkusen, Germany. It then plans to pilot a chemical process to recover TDA, from Q3 this year.

A spokesperson for Covestro said: “We need to optimise the process and develop the products in an industrial simulative environment. Nevertheless, if these trials are successful, Covestro intends to build an industrial plant which allows customers to buy materials in significant quantities, within the next couple of years.”

The recycling process starts with the collection of used mattresses, which are dismantled and the foam parts separated out. Some contain additives and fillers that hamper reprocessing. This separation is made more efficient using a sorting technology that relies on algorithms to identify the different types of foam.

Asked for more detail on the process, the spokesperson said: “The key steps for this innovative recycling are the intelligent sorting technology that we have developed together with our partners, Redwave and Recticel. And our own patented recycling technology, starting with a chemolysis step to dissolve the foam flakes, followed by purification steps and the hydrolysis to TDA, that needs to be further converted to the isocyanate.”

Speaking to the media last week, Sucheta Govil, COO at Covestro, said the company is committed to becoming fully circular, though declined to give a target date, saying it would be dependent on changes throughout the supply chain and in consumer behaviour.

“The circular economy is a global guiding principle. There iareno two ways about that…because all these challenges require a fundamental rethink. Production, consumption, and value creation must change significantly. The option to continue to think in a linear fashion does not exist any longer. Linear patters of consumption must be overcome, waste must be avoided wherever possible.”

“The plastics industry and the people who are in this business are equipped with the knowledge of these materials and processes. I would say we have a responsibility – and the ability – with our technologies to significantly support the transition to the much-needed circular economy.”

Separately, chemicals firm Dow is also working to recycle polyurethane from used mattresses but is focussed only on recovering polyols. Working with partners in France it aims to recycle up to 200,000 mattresses a year, producing polyols for reuse in mattress foams. Its chemicals recycling process is expected to produce recycled polyols for commercial re-use in the first half of this year.