From Waste to Value: Recycling Automotive Shredder Residue and Bio-Waste into High-Value Feedstock

  • ETH Zurich assesses the emissions of a new, non-fossil feedstock 
  • Feasibility of Chemical Recycling via gasification of mixed plastic waste demonstrated 

Ludwigshafen, Zurich, 30 October 2025. A new research study by ETH Zurich, in collaboration with BASF SE, has investigated an alternative route for mixed plastic waste streams from end-of-life vehicles: to recycle it alongside biomass. The results show: the recycling of one kg of automotive shredder residues with 3 kg of biomass reduces greenhouse gas emissions by more than 3 kg CO2-eq. as compared to their incineration for energy recovery. As the European Union prepares legislation on end-of-life vehicles, these findings have implications for policy makers.

The ETH study follows a gasification pilot project conducted by BASF and BEST GmbH/Austria mid of 2025. For the first time, the project in BEST’s pilot plant combined the gasification of biomass together with plastic waste from automotive shredder residue.

Less waste, new feedstocks, emissions reduced

This study shows: Instead of incinerating plastics and biomass to generate electricity and steam, co-gasification produces steam and synthesis gas, a valuable feedstock for chemicals. Providing this novel circular raw material to the chemical industry reduces consumption of fossil resources, thus lowering emissions and keeping carbon in the loop.

"Closing the carbon loop by plastics recycling is not only beneficial for the climate but also crucial for conserving resources, an essential step toward a plastics industry that operates within planetary boundaries," says André Bardow, Professor from ETH Zurich. 

However, to replace fossil feedstocks with alternatives made from plastic waste streams and bio-waste, a supportive legal framework is needed that acknowledges mixed plastic waste as recyclable and sets long-term targets to society for this replacement.

"Ambition in target-setting rather than opt-out and review clauses should be the baseline for policies that allow industries to reach ecological goals. Furthermore, sector-coupling and collaboration across industries is essential to speed up emission reductions," states Prof. Catharina Bening from ETH Zurich.

But while legislation already supports gasification of bio-waste - leading to first investments in maritime and aviation fuel - there is no comparable support for recycling plastic waste streams via gasification. "It is simply not efficient to operate separate gasification plants for bio-waste and for plastics waste streams. Instead, we call for policy to enable a multi-purpose of the plants through an audited, flexible mass balance approach," concludes Martin Jung, President of BASF’s Performance Materials division.

Using one million tons of plastic waste from end-of-life vehicles reasonably

The volume potential for non-fossil feedstock from automotive plastic waste is significant. Research estimates that over one million tons of automotive plastic waste is being either incinerated or landfilled in Europe every year. While there are opportunities to sort out more plastic waste (e.g., for mechanical recycling), there always remains a residual mixed plastic waste stream. The research results show that the recycling of this plastics waste, alongside biomass, is possible in a multi-purpose asset and results in lower CO2 emissions than via incineration for energy recovery.

Due to the high quality of the new circular raw materials stemming from this waste, the manufactured new materials, e.g. plastics, have the quality of new goods and meet the demanding requirements of high-performance plastics, as they are particularly needed for safety-relevant automotive components.