Towards circular plastics within planetary boundaries

Nature Sustainability, vol. 6, pp. 599–610

Abstract

Abstract The rapid growth of plastics production exacerbated the triple planetary crisis of habitat loss, plastic pollution and greenhouse gas (GHG) emissions. Circular strategies have been proposed for plastics to achieve net-zero GHG emissions. However, the implications of such circular strategies on absolute sustainability have not been examined on a planetary scale. This study links a bottom-up model covering both the production and end-of-life treatment of 90% of global plastics to the planetary boundaries framework. Here we show that even a circular, climate-optimal plastics industry combining current recycling technologies with biomass utilization transgresses sustainability thresholds by up to four times. However, improving recycling technologies and recycling rates up to at least 75% in combination with biomass and CO 2 utilization in plastics production can lead to a scenario in which plastics comply with their assigned safe operating space in 2030. Although being the key to sustainability and in improving the unquantified effect of novel entities on the biosphere, even enhanced recycling cannot cope with the growth in plastics demand predicted until 2050. Therefore, achieving absolute sustainability of plastics requires a fundamental change in our methods of both producing and using plastics.

Authors 7

1. Marvin Bachmann Aachen Institute for Technical Thermodynamics

   RWTH Aachen University

   Affiliation as printed

   Institute for Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

2. Christian Zibunas Aachen Institute for Technical Thermodynamics

   RWTH Aachen University

   Affiliation as printed

   Institute for Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

3. Jan Hartmann Aachen Institute for Technical Thermodynamics

   RWTH Aachen University

   Affiliation as printed

   Institute for Technical Thermodynamics, RWTH Aachen University, Aachen, Germany

4. Víctor Tulus

   ETH Zurich · Institute for Chemical and Bioengineering

   Affiliation as printed

   Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland

5. Sangwon Suh

   University of California, Santa Barbara

   Affiliation as printed

   Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA

6. Gonzalo Guillén‐Gosálbez

   ETH Zurich · Institute for Chemical and Bioengineering

   Affiliation as printed

   Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Zurich, Switzerland

7. André Bardow corresponding

   ETH Zurich

   Affiliation as printed

   Energy and Process Systems Engineering, ETH Zürich, Zurich, Switzerland