2024, Best Practice

Using Carbon Capture to Replace Fossil-Based Polyester Feedstocks with LanzaTech and On

LanzaTech is a technology company that harnesses biology to transform carbon emissions into raw materials. Together with sportswear brand On, the companies have worked to incorporate commercially viable polyester products from carbon capture technology into On’s supply chain. In this case study, Textile Exchange speaks with LanzaTech and On about how their partnership opened the door to scaling an apparel collection made using this technology.

Harnessing existing connections to scale innovative materials 

Swiss sportswear brand On has given itself the goal of reducing its Scope 3 greenhouse gas emissions by 55% by 2030. For a company that is heavily reliant on the performance characteristics of synthetic materials, this meant moving away from petrol-based chemicals and toward circular solutions. 

That’s where LanzaTech – a tech company setting out to build a circular carbon economy by repurposing waste carbon emissions as the feedstock for raw materials – came in. With a shared vision to prove that it is commercially viable to create products from carbon that would otherwise be released into the atmosphere, On and LanzaTech were both prepared to explore unknown avenues to make it happen.  

The two companies first teamed up in 2019 to produce an EVA (Ethylene vinyl acetate) foam made from waste carbon for On’s sneakers. After three years of problem-solving with multiple value chain partners and the successful proof of concept of On’s CleanCloud® foam later, the pair built on this success to tackle another of the key fossil fuel-derived materials in the sportswear supply chain: polyester. 

“LanzaTech is known as a leader, so it was a natural partner to choose,” explained a spokesperson for On. “We learned that innovation projects get done much faster if we collaborate with existing partners with the same mindset.” 

“We learned that innovation projects get done much faster if we collaborate with existing partners with the same mindset.”

Integrating “drop in” solutions into the supply chain

After discussions began in 2022, On released its first apparel collection made with CleanCloud® polyester from LanzaTech’s CarbonSmartTM technology in late 2023. In this solution, captured carbon emissions are turned into monoethylene glycol to replace 30% of conventional, virgin PET (polyethylene terephthalate), while the rest of the feedstock comes from purified terephthalic acid (PTA). 

Producing CarbonSmartTM polyester is a multi-step process, involving a range of actors along the way. Through a commercial-scale process, LanzaTech captures carbon emissions from industrial processes and ferments them into CarbonSmartTM ethanol. It then works with India Glycols Limited to convert the ethanol into monoethylene glycol (MEG), which is subsequently supplied to Far Eastern New Century, which turns it into PET.  

Given the complexity of the process, what allowed On to move from proposal to production so quickly this time?  Making the most of existing relationships.

Far Eastern New Century was already a listed supplier of On’s yarns and textiles, and LanzaTech had a pre-existing partnership with Far Eastern New Century making CarbonSmartTM polyester. Compared to the EVA foam project, this allowed the company to significantly reduce research and development and move quickly into the prototype and production phases.

The process was also made more straightforward by the fact that CarbonSmartTM MEG has the same material properties as fossil-based MEG, allowing it to function as a “drop-in” solution.

Taking a holistic approach to impact measurement

Beyond establishing CarbonSmartTM polyester as a commercially available solution, an equally important challenge was to understand its impact and see exactly how it can contribute to climate goals. “Carbon capture and utilization is a broad world, and the impact highly depends on feedstock source, technology, region, and infrastructure,” notes Kristen Allison, LanzaTech’s Global Business Development Director. 

LanzaTech invested in externally verified Life Cycle Assessments (LCAs), which enabled the company to understand the emissions savings of CleanCloud® polyester made with CarbonSmartTM technology when compared to its conventional counterpart. It also allowed the company to pinpoint where to focus future efforts to further reduce emissions.

This includes developing solutions for PTA – an area in which LanzaTech is now actively working. “The carbon footprint of the PET will be further improved once we can combine CarbonSmartTM MEG with renewable PTA technologies to address 100% of the PET content,” explained Allison. In addition, LanzaTech is working on a direct pathway to produce MEG without making ethanol first. 

Both companies also acknowledge the need to look at impact measurement holistically beyond LCA data and address sustainability from multiple angles. In practice, this means that beyond improving the carbon footprint of downstream materials, LanzaTech isn’t losing sight of its broader vision to create a circular carbon economy where emissions that would otherwise contribute to global warming are transformed into new raw materials that can be used instead of virgin fossil resources.

“Carbon capture and utilization is a broad world, and the impact highly depends on feedstock source, technology, region, and infrastructure.”

Committing to continual improvement going forward 

While LanzaTech has established a commercial supply chain for PET from captured carbon emissions, it is not afraid to admit that additional applications of the technology are a work in progress. For example, LanzaTech is developing a commercial-scale process to recycle textiles and other materials made with CarbonSmartTM ethanol by coupling a process called gasification with its gas fermentation technology.  

Ultimately, it wants textile waste that cannot be mechanically recycled to be gasified, and the resulting syngas to be fed to the biocatalyst and converted back to MEG (and/or PTA). This means that in a world where PET bottles might not be available as feedstocks for recycled polyester, fashion and apparel companies can operate within a circular system instead. 

For carbon capture technology to reach its full potential, LanzaTech notes that it needs systems on the industry side within which to communicate its sustainability attributes. “The industry needs to develop a framework for certification and traceability for new innovative next-gen materials such as carbon capture technologies,” Allison adds. 

According to On, accelerating and scaling these solutions will rely heavily on building strong relationships with partners that “not only embrace the technology, but are also open to continual innovation and improvements.”  

Ultimately, underpinning the success is the ability of different actors in the supply chain to come together with a mutual understanding. For this to work, “the foundation of open conversations, honesty, and a trust-based relationship is key,” a spokesperson summarizes for On.