Session
MO.3.A || Sustainable Chemicals and Materials

Authors
Meys, Raoul; Kätelhön, Arne; Bachmann, Marvin; Winter, Benedikt; Zibunas, Christian; Suh, Sangwon; Bardow, André

Abstract
Plastics production has 20-folded from 1964 to 2015 and is expected to reach 1,125 million tons by 2050 [1]. As a result of the exponential growth, plastics are expected to emit up to 8 Gt CO2-eq in 2050 [2]. To reduce these greenhouse gas emissions, disruptive technology changes are needed. Technologies avoiding emissions by closing the carbon cycle are therefore intensely developed. These circular carbon technologies comprise (i) chemical or mechanical recycling of plastics, (ii) carbon capture and utilization, or (iii) biomass utilization. Recent literature highlights the potential of these novel technologies to reduce greenhouse gas emissions [2]. However, it is still open how to achieve fully carbon-neutral plastics from a life cycle perspective using circular carbon technologies. At the same time, circular carbon technologies are perceived as energy- and cost-intensive, questioning the potential for large-scale implementation. In this presentation, we will assess the future circular life cycles of plastics. To do so, we use a global life cycle optimization model that includes more than 400 technology data sets and represents approx. 90% of global plastics production. Based on this model, we first calculate potential future circular life cycles for plastics. We present the mass flows required to achieve circular and carbon-neutral plastic life cycles. Finally, we will analyze the respective energy demands and operational costs for the future carbon-neutral plastic life cycle. Our results show that combining all the circular carbon technologies can lead to carbon-neutral plastic life cycles while consuming less energy and requiring lower operational cost than the fossil-based linear benchmark. [1] L. Neufeld, F. et al., The new plastics economy, Rethinking the future of plastics. (2016). [2] J. Zheng, S. Suh, Strategies to reduce the global carbon footprint of plastics. Nat. Clim. Chang. 9, 374–378 (2019)