摘要
加氢技术是炼油工业的支柱技术,其核心的加氢催化剂年消耗量超3×104t。加氢催化剂失活影响装置长周期稳定运行和整体经济效益,失活后加氢催化剂作为危险废物处理难度大。加氢催化剂失活主要原因分为积炭导致的暂时性失活,以及活性相结构变化、金属沉积、杂原子中毒和孔结构塌陷等导致的永久性失活。积炭通过覆盖活性中心或堵塞孔结构,造成催化剂活性下降,通过溶剂洗涤和氧化等方式可以再生恢复催化剂活性。高温长时间反应下催化剂活性相剥离或长大、金属沉积在催化剂表面和孔口、碱土金属沉积影响催化剂酸性中心、杂原子吸附在金属活性中心、分子筛孔结构发生不可逆塌陷,这些导致催化剂发生不可逆失活。柴油加氢催化剂失活主要由积炭造成,加氢裂化催化剂失活是由于活性金属组分聚集和分子筛酸性中心遭受不可逆破坏,渣油加氢催化剂失活主要因素有积炭和金属杂原子沉积等,加氢异构催化剂失活的主要原因是积炭覆盖了金属和酸性活性中心。通过溶剂处理和氧化再生等手段可以部分恢复催化剂孔结构和活性中心,活性恢复处理起到一定的金属再分散作用,部分恢复催化剂活性,因分子筛结构变化和碱金属杂原子沉积导致的酸性中心活性下降无法通过再生恢复。
Hydrogenation technology is a pillar for the refining industry,and the annual consumption of hydrogenation catalysts,the core of hydrogenation technology,is over 30000 tons.The deactivation of hydrogenation catalysts affects the long-term stable operation and overall economic benefits of the unit,and the deactivated hydrogenation catalysts are difficult to be treated as hazardous wastes.The main reasons for the deactivation of hydrogenation catalysts include the temporary deactivation caused by carbon deposition and the permanent deactivation caused by changes in structure of active phase,metal deposition,heteroatom poisoning,and collapse of pore structures.Carbon deposition can cause a decrease in catalyst activity by covering the active centers or blocking the pore structures,and the catalysts can be regenerated to restore activity through solvent washing and oxidation.In high temperature and prolonged reactions,the active phases of catalysts peel off or grow,metal deposits on the surface and pores of catalysts,alkaline-earth deposition affects the acid center of catalysts,heteroatoms are adsorbed on the active center of metal,and zeolite pore structures irreversibly collapse,leading to irreversible deactivation of catalysts.The deactivation of diesel hydrotreating catalysts is mainly caused by carbon deposition,the deactivation of hydrocracking catalysts is due to the aggregation of active metal components and the irreversible damage to the acid centers of zeolites,the deactivation of residue hydrodesulfurization catalysts is mainly caused by carbon deposition and metal heteroatom deposition,and the deactivation of hydroisomerization catalysts is mainly due to the carbon deposition that covers the metal and acid active centers.Through solvent treatment and oxidation regeneration,the pore structures and active centers of catalysts can be partially restored.The activity restoration treatment plays a certain role in metal redispersion,partially restoring the activity of catalysts.However,the activity decrease in
作者
张龙刚
Zhang Longgang(China Petrochemical Technology Co.,Ltd.,Beijing 100029)
出处
《中外能源》
CAS
2024年第11期69-77,共9页
Sino-Global Energy
关键词
加氢催化剂
积炭
金属沉积
失活
再生
研究进展
hydrogenation catalyst
carbon deposition
metal deposition
deactivation
regeneration
research progress
