Enhancing CO2 utilization: A review of long-chain α-Olefin synthesis via CO2 hydrogenation with Fe-based catalysts

The process of catalytic hydrogenation of carbon dioxide into long-chain α-olefins (LAOs, C₄₊⁼) offers a highly potential and advantageous approach for simultaneously addressing carbon emission reduction and the production of high-value chemicals. However, practical implementation is hindered by low LAO selectivity due to limited understanding of CO₂ activation, poor control over carbon chain growth, and catalyst design limitations. Despite enhancements in activity through modifications like adding promoters or creating dual active sites, the selectivity of LAOs remains suboptimal. Key challenges include promoting C-C coupling for olefin formation while minimizing over-hydrogenation and isomerization. This review provides a comprehensive overview of recent developments in Fe-based catalytic systems for CO₂-to-LAOs conversion, focusing on reaction mechanisms, catalyst modification strategies, and recent advancements in enhancing LAOs selectivity. Future research should focus on developing catalysts that enhance chain growth capability with increasing β-hydrogen elimination and suppressing excessive hydrogenation activity. This approach will help achieve a better balance between chain growth and appropriate olefin desorption, ultimately leading to higher yields of C₄₊ LAOs.