Designing the Ethylene Factory for Products of Carbon Dioxide Reduction: Techno-Economic and Life Cycle Assessments

The global ethylene market is rapidly expanding, and as demand grows, emissions are projected to rise, underscoring the urgent need for sustainable technologies to mitigate its carbon footprint. An original manufacturing approach integrated carbon capture and utilization (CCU), esterification, and dehydration to explore the utilization of intermediate chemicals for a circular economy. Initially, CO₂ was reduced to formic acid via electrocatalysis. Subsequently, esterification with ethanol produced ethyl formate, which was thermally catalyzed into ethylene. Comprehensive techno-economic and life cycle assessments identified opportunities and bottlenecks in designing this novel supply chain. Despite high production costs ($4.79 ± 1.19/kg), the environmental performance was promising. The LCA indicated a low carbon footprint, with up to 86% of emissions falling below benchmark levels (average 0.88 ± 0.55 kg CO₂ eq/kg), whereas other burdens exhibited an inverse trend. An original framework combining TEA-LCA, sensitivity analysis (SA), and uncertainty analysis (UA) was applied to forecast variability effects on the net present value (NPV) and product carbon footprint (PCF). Wastewater treatment, auxiliary materials, and CCU were primary contributors to the PCF’s uncertainty, leading to up to 90%, 45%, and 35% of the total variance, respectively. Operational expenditures (OpEx) related to power and raw materials accounted for up to 90% of NPV uncertainty. In contrast, total capital investment (TCI) and revenue (product and green credits from emissions-trading schemes, ETS) together contributed less than 10%. Improvements in yield, optimization of downstream processes, economic incentives, and/or the creation of a market for industrial flue gases as extra revenues are still necessary to compensate for high production costs and enable the deployment of the proposed technology to mitigate global warming burdens from ethylene production. In a complex decision-making process, technology mapping, cutoffs to fit the readiness level, green certification identification, UA, and SA for a combined TEA -LCA were identified as essential steps to guide future developments.

Net-zero ecosystem diagram for designing a circular economy with a sustainable supply chain for ethylene production from CCU and intermediate chemicals.