低温费托合成蜡油加氢裂化精制技术的研究进展

Research progress of low temperature Fischer-Tropsch synthetic wax oil hydrocracking refining technology

低温费托合成技术因具有产品质量性好、反应耗能低、生产能力大且催化剂种类广泛等优点在煤化工领域备受关注,低温费托合成的蜡油产品可通过加氢裂化精制获取高品质清洁油品,具有巨大的应用价值。本文首先阐述了费托合成的产物特性,分析了加氢裂化过程的反应特点、双功能催化剂的碳正离子反应机理及蜡油主要反应历程。在此基础上,着重综述了蜡油加氢裂化双功能催化剂的研究进展,讨论了活性金属组分、载体以及助剂对加氢裂化过程的影响,分析表明活性金属的负载量、载体的酸量和孔道结构对催化性能有极大影响,合理优化和平衡加氢金属活性位和裂解酸性位是确保蜡油加氢裂化催化剂活性的关键。更为重要的是,基于分子筛载体的择形效应,实现载体多级孔结构和活性位的理性集成无疑会促进蜡油加氢产物的合理分布。

Low-temperature Fischer-Tropsch(LTFT)synthesis technology has attracted much attention in the coal chemical industry owe to its advantages of good product quality,low reaction energy consumption,large production capacity and more selectable catalysts species.Wax oil obtained from lowtemperature Fischer-Tropsch synthesis can be refined to obtain high-quality clean oil by hydrocracking process.In this work,the product characteristics of Fischer-Tropsch synthesis was described,the reaction characteristics of wax oil hydrocracking,the reaction progress of wax oil and the carbocation reaction mechanism of the bi-functional catalyst in the hydrocracking process were listed and analyzed.Recent advances in hydrocracking bi-functional catalyst for wax oil hydrocracking have been emphatically introduced.Besides,the influence of active metal components,supports and additives on the hydrocracking process were also discussed.The analysis shows that the loading of active metals,the acid content and pore structure of the carrier have a great influence on the catalytic performance.The key of improving the activity of hydrocracking catalysts is the optimization and reasonable matching between the active sites of hydrogenation metal and the acid sites of cracking.In addition,the integration of compositemulti-model pores and active sites undoubtedly improve the product distribution and product property of wax oil hydrocracking based on the shape selectivity of zeolite.