Linear α-olefins are currently produced predominantly by the oligomerization of ethylene. Among the most promising catalysts, zirconium catalysts are largely studied due to its mild reaction condition and well-distributed products. In this article, aryloxy zirconium catalysts, Zr( OAr) n Cl4-n ·mArOH, were synthesized via modifying the aryl ring structure. The influence of Zr/Phenol molar ratio and the free phenol content on ethylene oligomerization was studied. Among these catalytic systems, Zr(OPh)3Cl·mPhOH/TEA/EtAlCl2 was proved to be highly active with the activity up to 6. 8×104 g/(mol Zr·h), while the product consisted of mainly α-olefins( C4—C24 ) without polymers. In addition, a suitable amount of free phenol was found to be responsible for stabilizing the active species. It was also found that increasing the ethylene pressure or altering the substituents on the benzene ring could result in the formation of a tandem catalytic system, in which the obtained α-olefins were then mostly converted into the corresponding Friedel-Crafts alkylated-toluene products.%从锆系催化剂的结构修饰出发,合成了一系列具有Zr(OAr)nCl4-n·mArOH(n=1~4, m=0~7)结构的芳氧基锆系催化剂,并研究了锆酚配比及游离 ArOH 含量等对乙烯齐聚行为的影响.结果表明, Zr(OPh)3Cl·mPhOH/TEA/EtAlCl2催化体系具有较高的齐聚催化活性[6.8×104 g/(mol Zr·h)],所得产物主要为C4~C24的α-烯烃,无高聚物生成.研究发现,游离酚的存在对体系的催化性能有较大影响.该系列芳氧基锆系催化剂可催化乙烯齐聚与Friedel-Crafts烷基化的串联反应,即齐聚反应产物α-烯烃与甲苯溶剂发生烷基化反应而生成多取代芳香烃,压力越大烷基化反应程度越高.
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