Covestro says investments boost polyurethane recycling

German-based polymers producer Covestro AG says it is working to “align itself comprehensively with circularity and help make it the global guiding principle” as it develops technologies to reuse plastics and return them to the value cycle, “often in close cooperation with partners.”

The goal of one new collaboration, with Switzerland-based backpack and messenger bag producer Freitag, is “the unlimited recycling of truck tarps, based on thermoplastic polyurethanes (TPUs),” Covestro says. At the end of their useful life, the tarps are to be recycled via a chemical recycling process and used for new tarps or other products, the firm says.

Covestro says its focus to date has been on proven mechanical recycling to obtain materials. More recently, it sees chemical recycling processes, in which polymer molecules are broken down chemically, as a way forward.

Calling mechanical recycling “particularly suitable for polycarbonates,” Covestro says numerous corresponding products from Covestro are already on the market, including polycarbonate blends for IT applications with up to 75 percent recycled material.

“In addition, new plastic products are designed from the outset to be easier to recycle at the end of their useful life,” the company says.

A consortium of industrial partners in the Circular Foam project is researching processes for the chemical recycling of rigid polyurethane foam, according to Covestro, which says it is guiding that effort.

Polyurethanes (PU) and other thermoset products are difficult to mechanically recycled, according to Covestro, which calls chemical processes “the obvious choice” for PU. Covestro says it has developed an innovative technology for recovering both core raw materials in PU mattress foam as part of a research project with partners.

These materials, polyols and the isocyanate TDI, are used in the production of mattress foam. The precursor is recovered from the TDI, and both raw materials can be reused for the production of new foam after reprocessing. “The results achieved to date are being tested in a pilot plant at the Leverkusen [German] site,” the company says, and Covestro has introduced the Evocycle brand name for the project.

Covestro is cooperating with recycling firm Interseroh, an Alba Group company, to developed collection and processing of recyclables so they ultimately can be supplied to Covestro for chemical recycling. Covestro is pursuing a similar goal in its cooperation with the French environmental protection organization Eco-mobilier, which specializes in the collection and recycling of old furniture.

The Circular Foam research project consists of 22 industrial partners from nine countries, coordinated by Covestro, says the firm. “Over the next four years, experts from science, industry, and society want to develop a comprehensive solution model for the waste management and recycling of such foams,” Covestro says.

The company estimates the Circular Foam effort has the potential to divert for recycling up to 1 million metric tons of waste material per year in Europe.