Chemical recycling of plastic scrap is gaining momentum, according to UK-based consultancy IDTechEx. In the article below, IDTechEx explores early stage technologies in chemical recycling and assesses the players and potential commercial impact. For an in-depth analysis of the chemical recycling market, consider IDTechEx’s new market report, Chemical Recycling and Plastic Melting 2023-2033.
When it comes to chemical recycling, headlines about investments, planned expansions and actual product launches are all accelerating in frequency and magnitude. Is this market currently at the stage of large-scale implementation, regulatory developments, improved tracking and accounting methods, or is there still a need for technological developments?
The concept of chemical recycling is to return used plastics to monomer feedstocks or further upstream in raw materials so that they can be re-introduced into the value chain in virgin grade quality. .
Much criticism remains in this area, particularly with respect to its economic and environmental viability, with lobbying and activist groups prominent on both sides of the debate.
As with everything, reality is more nuanced. Are these processes the perfect solution for all your sustainable polymer needs? Not at all? Of course, the sustainability debate does not simply focus on chemical recycling, but this article sets this debate aside and focuses on current and future technological solutions.
Depolymerization. this technique One of the most exciting areas of chemical recycling. We need to break the polymer chain into its monomers. This is not suitable for all polymers, but works very well for some. Monomers are also more valuable than raw materials, but there are challenges such as process conditions and the requirement for more homogeneous scrap feedstocks, to name two.
A major commercial frontier is the depolymerization of polyethylene terephthalate (PET) via methanolysis, hydrolysis, glycolysis, or thermal depolymerization of polystyrene (PS). PET’s role in the high-volume industries of PET bottles, other packaging, and textiles has made PET a key focus area being explored by both young and established companies. [petrochemical] Most prominently in Eastman’s 2022 announcement.
Although there are some early stage technological developments, such as the use of ionic liquids, there are two notable processes close to large-scale deployment.
1. Enzymatic depolymerization. This is the use of natural or engineered enzymes to break down plastic scrap. [The field shot into prominence in 2012 with the discovery in Japan of LCC (leaf-branch compost cutinase) and now includes many more, including leveraging artificial intelligence (AI) in the engineered design as demonstrated by the University of Texas-Austin. This depolymerization approach is typically focused on PET but not limited there, with opportunities with polyurethane (PU), polycarbonate (PC), polyamides (PA) and more, and commercial engagement is increasing. The most prominent company is Carbios, which announced in 2022 it would build its first plant in partnership with Thailand-based Indorama Ventures. The company has an agreement with Novozymes to produce the proprietary recycling enzyme and end-user partnerships, including Pepsi, L’Oréal, On, Patagonia, Salomon, Puma, Nestle Waters and Suntory Beverage & Food Europe. Carbios is not alone, as many others enter this field. Another emerging company is Samsara Eco in Australia. In late 2022, it announced a $36.5 million Series A funding round to build its first plant. It expects its recycled packaging on supermarket shelves in 2023 in partnership with Woolworths Group.
2. Microwave-assisted depolymerization. When approaching thermal depolymerization, the ability to achieve efficient heat transfer is essential; this is where microwaves could play a role. As with enzymatic processes, there remains a large amount of academic interest, but the commercial success stories are increasing. One of the key players in the field is Pyrowave. Canada-based Pyrowave has been operating a reactor for PS for many years and has reported that its recycled product has already gone into many finished goods. Tire producer Michelin is a key investor and is in the process of installing its first multi-reactor project with the product utilized for its styrene-butadiene rubber. There are others exploring microwaves, including Microwave Chemical in Japan, which works with Mitsubishi Chemical on Poly(methyl methacrylate) [ PMMA] and other efforts, and Switzerland-based Gr3n, which was funded by Chevron Technology Ventures and Standex International in 2021, are eyeing PET.
Thermal decomposition. Using a pyrolysis process for plastic scrap is not a new concept. This process has been the subject of decades of research and commercial exploration. The reasons for the positive forecast relate to market drivers leading to commitments from major petrochemical companies such as BASF, Sabic and ExxonMobil. In 2022 alone, Encina announced his $1.1 billion investment in a new factory. Plastic Energy advances commercialization with announcements on TotalEnergies, Ineos, LyondellBasell and Qenos. Similarly, Honeywell announced a strategic agreement with TotalEnergies and a joint venture with Avangard. However, as we said earlier, not all are positive. In 2022, lawmakers and environmental groups have submitted more than 100 of his letters to the U.S. Environmental Protection Agency (EPA) on how this is regulated, but Brightmark Energy, for example, has his 680 million There have been setbacks, including plans to scrap a $10,000 plant. Get ready for more news in 2023.
Pre-treatment (degree of selection, form factor considerations), post-treatment (purity, cracker considerations), and the process itself (yield, molecular weight distribution, light gas recycling, durability, etc.) have many implications. There are technical challenges. The incremental changes available are limited, but the technology is definitely improving at each stage.
other technology. One of the notable technological developments in related fields is hot water liquefaction. Here, supercritical water and a catalyst are used to decompose mixed polymers into long-chain hydrocarbons. One of the reported advantages is the ability to withstand low-quality mixed material feedstocks, especially those with a high proportion of polyvinyl chloride (PVC), which is a key thermal decomposition problem. As with pyrolysis, this is nothing new, but young companies are gaining a lot of momentum, most notably Licella. Through joint ventures and other engagements, Australia-based Licella’s core technology has evolved into strategic partnerships and planned projects with Dow, Mitsubishi Chemical, LG Chem and others.
Similarly, gasification is not a new process and is widely deployed to remove municipal solid waste (MSW), especially in Japan. What’s changing is the idea that the syngas produced doesn’t need to be used as on-site energy, but rather can be purified and converted into longer chain hydrocarbons, methanol or ethanol. Because MSW can be used, gasification serves as a final option for circulation before incineration. Players are investigating this. Enerkem is one of the players to watch, with the first commercial plant opening in 2014. As of late 2022, Enerkem said he has one more plant under construction for 2023, and he has two more planned. Note that similar to pyrolysis, the product may re-enter the supply chain, but in many cases it will not and will be used as a fuel instead.
Not to be overlooked are other processes that are not covered in this article. This can range from developing polymers with dynamic bonding to promote a circular economy to secondary recycling processes for melting or refining plastics. Although the latter is not chemical recycling, it is a promising route that can achieve higher-grade materials than other mechanical routes without going back up the value chain. It has expanded its commercial activities through Trinseo, PureCycle Technologies, APK, Polystyvert, Worn Again and others. As with other processes, many of the young technology providers value the plastic he boasts partnerships with big players across his chain.