【科技日报】为铁基费托合成装上“分子开关”

Core Insights - The research team successfully reduced carbon dioxide byproduct content in iron-based Fischer-Tropsch synthesis from approximately 30% to below 1% by adding halogen compounds at a concentration of one part per million, while increasing the yield of high-value olefins to over 85% [1][2][3]. Group 1: Current Challenges in Fischer-Tropsch Synthesis - Fischer-Tropsch synthesis is a crucial catalytic reaction technology in the chemical industry, primarily used to convert syngas (a mixture of carbon monoxide and hydrogen) into liquid fuels or high-value chemicals [2]. - The iron-based catalyst is favored in over two-thirds of industrial processes due to its low cost and high oil production rate, but it is associated with significant carbon dioxide emissions [2][3]. - Traditional iron-based Fischer-Tropsch synthesis processes often have a carbon dioxide selectivity as high as 30%, meaning that for every 100 carbon atoms converted, 30 become greenhouse gases [2][3]. Group 2: Innovative Halogen Regulation Strategy - The research introduces a trace halogen regulation strategy, where halogen compounds like bromomethane and iodomethane are added to the reaction gas at a concentration of one part per million [3][4]. - This strategy acts as a "molecular switch," effectively blocking the pathway that generates carbon dioxide while enhancing the production of olefins [4]. - The addition of halogen compounds prevents excessive hydrogenation of hydrocarbons, allowing more carbon atoms to be utilized for olefin production [4]. Group 3: Practical Implications and Future Directions - The halogen regulation strategy is practical and convenient, requiring no major modifications to existing catalysts or equipment, only the addition of trace halogen gases at the inlet [4][5]. - The research team is actively collaborating with relevant enterprises for pilot-scale testing and long-term stability assessments, aiming to expedite the industrial application of this strategy [5]. - Key challenges for industrialization include precise dosing and concentration control of halogen compounds, ensuring the stability of iron-based catalysts over long operational periods, and adapting the strategy to different gasification feedstock compositions [5].