Abstract
Ethylene is a key platform chemical in global manufacturing, yet its conventional production via steam cracking is highly energy-intensive and a major source of industrial CO2 emissions. This study proposes a sustainable alternative for ethylene synthesis through the electrochemical reduction of captured CO2 via alkaline electrolysis powered by intermittent offshore wind energy. A selective catalytic pathway for the CO2 reduction reaction is identified and modeled in ASPEN PLUS®, with full integration of reaction, separation, and recycle units. To address the variability in renewable energy supply, a time-variable process optimization framework is developed in Pyomo, enabling operational flexibility through integrated process planning and scheduling. Three electricity sourcing scenarios are analyzed, each representing different balances between grid and renewable power. A gate-to-gate life cycle assessment reveals a significant greenhouse gas emission reduction, with the most renewable-intensive configuration achieving net-negative emissions of −2.4 kgCO2 per kg ethylene produced. This represents a substantial improvement over conventional fossil based processes and a notable reduction compared to the state of research on CO2-based processes, demonstrating the potential for de-fossilizing ethylene production on a large scale. The break-even ethylene price is calculated at 6.06 euro per kg, and the required carbon certificate price is 1,770 euro per ton. While the process is not currently cost-competitive, it shows significant potential for viability given technological cost reductions and future market or policy conditions. These findings highlight the technical feasibility and environmental advantages of renewable-powered, CO2-to-ethylene conversion, offering a promising pathway for decarbonizing ethylene production and reducing fossil dependency in the chemical sector.