乙烯三聚/四聚用铬系催化剂配体的研究进展

Research progress of ligands in chromium-based catalysts for ethylene trimerization/tetramerization

综述了近年来乙烯三聚/四聚用铬系催化剂所用PNP型配体及其他类型配体(如PNS型、NNN型、PN-(CH_(2))_(n)-NP型、PCCP型配体)的研究进展。其中,PNP型配体对1-辛烯的选择性最高可达72.52%,活性最高达9.46×10^(6)g/(mol·h)。其他类型配体对1-辛烯的选择性最高可达76.00%,活性最高达1.71×10^(7)g/(mol·h)。分析了不同类型配体骨架上N,P原子取代基种类、空间体积、供电子及吸电子性能对催化剂催化乙烯三聚/四聚活性和选择性的影响,增大空间体积或配体上的供电子原子均能提高对乙烯三聚/四聚的活性和选择性。目前,副产物较多致使管路堵塞、助催化剂成本较高等是实现乙烯四聚工业化所要解决的问题。

The research progress of PNP-type ligands and other types of ligands such as PNS type,NNN type,PN-(CH_(2))_(n)-NP type,PCCP type used in chromium catalysts for ethylene trimerization/tetramerization in recent years is reviewed.The selectivity of PNP-type ligands to 1-octene is 72.52%,and whose activity is up to 9.46×10^(6)g/(mol·h).The selectivity of other ligands for 1-octene is up to 76.00%,and whose activity is up to 1.71×10^(7)g/(mol·h).The effects of N and P substituents in ligand skeleton,space volume,electron donor and electron attractor on the activity and selectivity of ethylene trimerization/tetramerization were analyzed.The increase of space volume or electron donor atom on the ligands can improve the activity and selectivity of ethylene trimerization/tetramerization.The problems such as pipeline clogging due to more by-products and higher cost of cocatalyst need be solved in the industrialization of ethylene tetramerization.