A large share of everyday waste — from households, businesses, agriculture, and industry — still ends up in landfills or is incinerated for energy recovery. These methods have drawbacks that, if not properly managed, can harm the environment.
Today, however, a shift in perspective is underway. Post-use waste is increasingly seen as a carbon-rich feedstock that can be transformed into valuable products through innovative technologies. These technologies help reduce CO₂ emissions associated with incineration and prevent the soil and water pollution linked to landfilling.
While biological methods like anaerobic digestion have long been used to convert organic materials into biogas, new physical and chemical processes — including pyrolysis, gasification and hydrothermal treatments — are expanding the possibilities [1]. Waste typically contains a mix of materials, including plastics, organic matter, paper, metals, and textiles. Different technologies are needed to handle each type of waste material, with many of the new chemical processes designed to improve recycling efficiency for specific fractions — particularly plastics.
In Europe, just over a quarter (26.9%) of plastic waste was recycled in 2022, and only 13.5% of new plastic materials came from recycled content. From a regulatory standpoint, the European Union (EU) aims to raise these figures by 2030, setting targets for circular plastic content across sectors. Achieving those goals will require scaling up advanced recycling methods that are both efficient and environmentally sound.
Mechanical recycling of plastics — the standard approach — has clear limits, particularly when dealing with mixed or contaminated plastics. Chemical recycling of plastics is emerging as a powerful complement to mechanical recycling processes. Chemical recycling can handle more complex waste streams, recover valuable materials, and close the loop on plastic waste more effectively.
The case for chemical recycling
Chemical polymer recycling holds tremendous potential to reduce both waste and emissions. A recent study [2] found that if Europe fully scaled its recycling capabilities, CO₂ emissions from plastics could be significantly reduced. Chemical recycling is especially promising for producing polyolefins like polyethylene and polypropylene — common plastics that can be difficult to recover through mechanical means.
Among the available technologies for chemical recycling of plastics, gasification stands out for its ability to handle mixed and heterogeneous feedstocks. Lifecycle assessments have identified gasification as a low-emission pathway for recycling mixed polyolefins. A recent study [2] found that it generated just 100 million tonnes of CO₂ — or 37% of total emissions from all polymer recycling methods — far lower than the emissions associated with incineration with energy recovery. In addition to its lower emissions profile, gasification is also highly versatile in the range of end products it can produce.
Figure 2. Chemical recycling is required to make the best use of mixed streams of plastic waste
Gasification and beyond: exploring the next frontier of plastics recycling
Gasification is a thermochemical process that transforms carbon-rich waste into syngas — a mix of hydrogen (H₂) and carbon monoxide (CO). Unlike incineration, which primarily produces heat and CO₂, gasification offers the potential to generate valuable feedstocks for new plastics and chemicals, enabling true circularity.
However, much remains unknown about how best to harness gasification and other advanced processes to recover olefins — the essential building blocks for new plastics — in a way that is environmentally and economically viable. While some studies suggest that polyolefins like polyethylene and polypropylene perform well in these processes, especially when aided by catalysts, the performance, efficiency and emissions outcomes can vary widely depending on technology choices, process design and feedstock characteristics. The sector lacks a clear understanding of which configurations offer the greatest environmental and economic benefits.
To better understand the opportunities and trade-offs in advanced recycling, the Global Impact Coalition and five of its member companies — BASF SE (www.basf.com), Clariant AG (www.clariant.com), Covestro (www.covestro.com), LyondellBasell (www.lyondellbasell.com), and SUEZ (www.suez.com) — are partnering with scientists from ETH Zurich on a new research initiative. The study is exploring different pathways for converting plastic waste into olefins — from indirect methods that produce syngas and convert it via intermediates, to more direct thermal and catalytic approaches. Each route offers unique advantages and challenges in terms of emissions, energy use, and product yields.
Given the early stage of these technologies, the study will apply lifecycle-based environmental assessments to estimate their best-case potential. The goal is to identify which conversion routes hold the greatest promise for scaling, and what performance benchmarks must be met for them to offer a credible alternative to fossil-based production. This work will help shape where future innovation and investment should be focused.
Innovation for a circular future
As pressure mounts to decarbonize and reduce plastic waste, advanced recycling technologies like gasification will play an increasingly vital role. But to unlock their full potential, a clearer understanding is needed of which pathways offer the greatest value — environmentally, economically and at scale.
With smart investment and focused research, we can move beyond outdated waste management practices and build a more circular, lower-emission plastics economy. The Global Impact Coalition’s collaboration with ETH Zurich researchers is a step toward that future — one where waste is no longer a liability, but a feedstock for progress.
References
1. Towards a circular economy for plastic packaging wastes – the environmental potential of chemical recycling – ScienceDirect
2. Plastic recycling in a circular economy; determining environmental performance through an LCA matrix model approach – ScienceDirect
Further reading
Towards circular plastics within planetary boundaries | Nature Sustainability
Renewable carbon feedstock for polymers: environmental benefits from synergistic use of biomass and CO2 – Faraday Discussions (RSC Publishing)
Recent evolution in thermochemical transformation of municipal solid wastes to alternate fuels – ScienceDirect
Two-step conversion of waste plastic into light olefins and aromatics on metal-free carbon felt catalyst under radiofrequency heating – ScienceDirect
Valorization of Municipal Solid Wastes in Circular Economy | SpringerLink
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