A catalyst BCLN for ethylene slurry polymerization was prepared by dissolving and precipitation method. The precipitation process was studied by SEM and particle size distribution instrument. Characterization results show that BCLN catalyst generated uniform nano-scaled secondary particles at first,and eventually aggregated to form catalyst particles. The polymerization performance of BCLN and imported reference catalyst Cat-r were compared. The results showed that the morphology and particle size distribution of BCLN were better than that of Cat-r. The activity and hydrogen response of BCLN were better than that of Cat-r. The size distribution of the polymer powder produced by the BCLN catalyst was narrow. Particles larger than 850μm and fine powder smaller than 75μm in the polymer powder produced by BCLN were significantly less than that produced by the Cat-r catalyst. The polymerization kinetics curves of the two catalysts belonged to the attenuation form. Within the ethylene polymerization of 2 h,the activity of the two kinds of catalysts was relatively stable and the activity decay was relatively slow.%采用溶解析出法制备了适用于乙烯淤浆聚合工艺的催化剂BCLN,利用SEM和粒度分布仪研究了催化剂析出过程的变化.表征结果显示,BCLN催化剂析出时首先生成粒径均匀的纳米级次级微粒,最终聚集形成催化剂颗粒.将BCLN和进口参比催化剂Cat-r进行了性能的对比,实验结果表明,BCLN催化剂的形貌和粒径分布优于Cat-r,聚合活性和氢响应性也优于Cat-r.BCLN催化剂聚合所得聚合物粒径分布更集中,粒径在850μm以上的颗粒明显少于Cat-r制备的聚合物,粒径在75μm以下的细粉含量较低.两种催化剂的聚合动力学曲线均属于衰减型,在2 h聚合时间内,催化剂的活性较平稳,活性衰减速率较缓慢.
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