Sustainable Ethylene Production via CO₂ Capture and Electroreduction
摘要
The electrochemical reduction of carbon dioxide (CO₂R) offers a promising pathway to simultaneously mitigate greenhouse gas emissions and meet the growing global demand for ethylene (C₂H₄), a critical chemical feedstock. This review summarizes the latest advancements in CO₂-to-ethylene conversion, focusing on renewable energy-driven electroreduction technologies. Key developments in catalysis, particularly copper (Cu)-based systems, which demonstrate exceptional selectivity for C₂H₄, are examined alongside innovations in electrochemical cell design, process integration, and energy efficiency. Theoretical insights underpinning these advancements, including density functional theory (DFT) predictions of reaction pathways and intermediate stabilization, are critically examined. Recent breakthroughs, including novel catalyst modifications, zero-gap membrane electrode assemblies (MEAs), and strategies for coupling intermittent renewable energy, have achieved Faradaic efficiencies exceeding 70% for ethylene in optimized systems. However, scaling these processes to industrial levels remains a challenge. Persistent obstacles include maintaining high selectivity at industrially relevant current densities, ensuring long-term catalyst stability, improving low product yields, reducing energy demands, and seamlessly integrating CO₂ capture with electroreduction units. Potential solutions, such as advanced catalyst engineering, optimized reactor configurations, and leveraging surplus renewable energy, are explored to enhance sustainability and scalability. Ultimately, this review highlights the transformative potential of combining CO₂ capture with electrochemical reduction to enable greener ethylene production while addressing pressing environmental concerns.