Realizing the potential high benefits of circular economy in the chemical industry: ethylene monomer recovery via polyethylene pyrolysis

Abstract

The concept of circular economy has gained wide interest in industry as a powerful strategy to reduce impacts while remaining economically competitive. Here, we explore the benefits of this approach in the chemical industry, quantifying explicitly the economic and environmental benefits of ethylene recovery from polyethylene plastics using process modeling coupled with Life Cycle Assessment (LCA). Our results show that the recovered ethylene represents a win-win alternative, offering a highly competitive cost of 0.386 €/kg vs 0.835 €/ kg with the standard naphtha-based route. Furthermore, substantial reductions of as much as 87%, 89%, and 164% could also be attained (compared to the naphtha-based ethylene) in impacts on human health, ecosystem quality, and resources scarcity, respectively. Overall, this work aims to promote the adoption of circular economy strategies in the chemical sector, while highlighting the role of process modeling, LCA, and systems thinking in quantifying the associated benefits to build strong cases for policymaking.