The bridge between linear and circular
SABIC, which is among the world’s largest petrochemicals manufacturers, will be a first-time exhibitor at INDEX™20 this October.
The $26 billion-turnover corporation is now emerging as a strong collaboration partner to nonwovens manufacturers with its Purecares dedicated portfolio of polypropylene (PP) and polyethylene (PE) for absorbent hygiene products (AHPs).
Launched at the beginning of 2020, Purecares consists of dedicated ranges of polymers for nonwovens, films and laminates – including those based on SABIC Trucircle circular PP, using feedstock derived from previously used plastics.
SABIC has already partnered with leading nonwovens manufacturer Fibertex Personal Care to announce an industry milestone at the beginning of December last year – the first nonwovens based on circular PP.
The nonwovens are created from post-consumer mixed plastics that have been broken down into their molecular building blocks and then re-polymerized to create virgin plastics.
The new circular PP can be used as a drop-in solution while meeting the brand owner’s requirements for purity and consumer safety AHP applications.
SABIC applies the mass balance approach to polymers offered as part of its Trucircle portfolio and services, which span design for recyclability, mechanically recycled products, certified circular products from feedstock recycling of used plastics, and certified renewable products from bio-based feedstock.
The widely recognised ISCC PLUS certification verifies that mass balance accounting follows predefined and transparent rules. In addition, it provides traceability along the supply chain, from the feedstock to the final product.
In recent years, the mass balance approach has prevailed in the chemical industry. As an important milestone on the pathway to a circular economy and bioeconomy, it has been designed to trace the flow of materials through a complex value chain. Since chemically recycled or bio-based feedstocks are typically blended in the manufacturing complex, physical segregation of recycled content is often practically and economically unfeasible. The mass balance approach makes it possible to track the amount and sustainability characteristics of circular and/ or bio-based content in the value chain and attribute it, based upon verifiable bookkeeping.
“Mass balance is considered a crucial bridge between today’s large scale linear economy and the more sustainable circular economy of the future, which today is operated on a smaller scale but is expected to grow quickly,” said Mark Vester, global circular economy leader at SABIC.
Fibertex Personal Care has also achieved ISCC PLUS certification for its circular PP nonwovens and is now supplying them in its Comfort, Elite, Dual and Loft product ranges. These certified nonwovens can be adopted in downstream processes, without compromising convertibility, product properties or performance of the final product.
“This is an important step forward in the development and expansion of a supply chain for bio-based and circular polymers,” said Fibertex Personal Care CEO Mikael Staal Axelsen: “The Trucircle initiative made it possible and we are proud to cooperate with SABIC.”
SABIC has also recently teamed up with Procter & Gamble and the Fraunhofer Institute UMSICHT in a pilot project aimed at demonstrating the feasibility of the closed-loop recycling of single-use facemasks.
The use of billions of disposable facemasks during the Covid-19 pandemic has raised environmental concerns and in addition to the challenge of dealing with such huge volumes of essential personal healthcare items in a sustainable way, simply throwing the used masks away for disposal on landfill sites or in incineration plants represents a loss of valuable feedstock for new material.
“We set out to explore how used facemasks could potentially be returned into the value chain of new facemask production”, said Dr Peter Dziezok, director of R&D and open innovation at P&G. “But creating a true circular solution from both a sustainable and an economically feasible perspective takes partners. We therefore teamed up with Fraunhofer UMSICHT’s expert scientists and SABIC’s technology and innovation specialists to investigate potential solutions.”
As part of the pilot, P&G collected used facemasks worn by employees or given to visitors at its manufacturing and research sites in Germany. Although these masks are always disposed of responsibly, there was no ideal route in place to recycle them efficiently. To help demonstrate a potential step change in this scenario, special collection bins were set up, and the collected used masks were sent to Fraunhofer for further processing in a dedicated research pyrolysis plant.
“A single-use medical product such as a facemask has high hygiene requirements, both in terms of disposal and production,” explained Dr Alexander Hofmann, head of recycling management at Fraunhofer UMSICHT. “Mechanical recycling would not have done the job. In our solution, therefore, the masks were first automatically shredded and then thermochemically converted to pyrolysis oil.
“Pyrolysis breaks the plastic down into molecular fragments under pressure and heat, which will also destroy any residual pollutants or pathogens, such as the coronavirus. In this way it is possible to produce feedstock for new plastics in virgin quality that can also meet the requirements for medical products.”
The pyrolysis oil was then sent to SABIC to be used as feedstock for the production of new PP resin. The resins were produced using the mass balance approach, to combine the alternative feedstock with fossil-based feedstock in the production process.
“The high-quality circular PP polymer obtained in this pilot clearly demonstrates that closed-loop recycling is achievable through the active collaboration of players from across the value chain,” said Mark Vester.
Closing the loop
Finally, to close the loop, the PP polymer was supplied to P&G, where it was processed back into new nonwoven materials.
“This pilot project has helped us to assess if the closed loop approach could work for hygienic and medical grade plastics”, said Hansjörg Reick, P&G’s senior director of open innovation. “Of course, further work is needed but the results so far have been very encouraging.”
The entire closed loop pilot project from facemask collection to production was developed and implemented within only seven months. The transferability of advanced recycling to other feedstocks and chemical products is now being further researched at Fraunhofer.