摘要
近80年以来,轻质烯烃特别是乙烯与丙烯,主要通过石油烃类蒸汽裂解生产。与蒸汽裂解相比,催化裂解过程引入了催化剂,使其操作条件温和,高附加值产品收率提高,有望成为未来制烯烃技术的主要工艺路线。本文总结了目前国内外典型制低碳烯烃工艺的优缺点与应用现状,概述了催化裂解工艺中自由基机理和碳正离子机理等主要反应机理,探讨了金属氧化物催化剂和沸石分子筛催化剂的使用性能,重点分析了碱金属和碱土金属、过渡金属、稀土元素改性对ZSM-5沸石分子筛性质的影响以及所得催化剂提高低碳烯烃选择性的性能特征。指出以大型工业化装置的开发、原料范围的持续扩大、高品质催化剂的研发为催化裂解工艺发展的主要研究方向,为低碳烯烃工业化生产提供重要参考。
In recent 80 years,light olefins,especially ethylene and propylene,have primarily been produced through steam cracking of petroleum hydrocarbons.Compared with steam cracking,catalytic cracking introduces a catalyst into the process,which makes its operating conditions mild and improves the yield of high value-added products.It is expected that catalytic cracking will become the primary process for olefin production technology in the future.This paper provides a summary of the advantages and disadvantages of common low-carbon olefin production processes both domestically and internationally,as well as their current application status.It outlines the primary reaction mechanisms involved in catalytic cracking,including the free radical mechanism and the carbon positive ion mechanism.Additionally,it discusses the use of metal oxide and zeolite molecular sieve catalysts.The text focuses on analysing the effects of alkali and alkaline earth metals,transition metals,and rare earth elements modification on the properties of ZSM-5 zeolite molecular sieves.The resulting catalysts were analysed for their performance characteristics in improving the selectivity of low carbon olefins.The main research directions for the development of the catalytic cracking process include the development of large-scale industrialized devices,the continuous expansion of feedstock range,and the research and development of high-quality catalysts.These directions will provide an important reference for the industrialized production of low-carbon olefins.
作者
孙傲
田晓春
王成宇
丁康乐
SUN Ao;TIAN Xiaochun;WANG Chengyu;DING Kangle(College of Chemistry and Environmental Engineering,Yangtze University,Jingzhou,Hubei 434023,China)
出处
《世界石油工业》
2024年第2期91-101,共11页
World Petroleum Industry
基金
国家自然科学基金面上项目“页岩沉积层中无机氮转化为有机氮的化学机理与氮同位素演化”(41472095)。
关键词
石油烃类
催化裂解
低碳烯烃
催化剂
ZSM-5分子筛
petroleum hydrocarbons
catalytic cracking
low-carbon olefins
catalyst
ZSM-5 zeolites
