Raney-Ni催化剂的磁固载及其应用

 Raney-Ni催化剂由于价格便宜且催化活性高,在加氢反应中有广泛的应用,但其催化活性会随使用次数的增加而迅速下降. 通过对Raney-Ni催化剂的SEM照片及粒度分布进行分析可知,在不饱和乙内酰脲加氢反应过程中,催化剂活性下降的主要原因是催化剂的粉化流失和活性位点镍微晶的熔合. 在反应体系中添加磁性材料KF-610后,减少了批次反应过程中催化剂的流失及活性的快速下降,可实现催化剂的回收利用及活性维持. 经20批次亚苄基乙内酰脲、对羟基亚苄基乙内酰脲和吲哚亚甲基乙内酰脲加氢反应,不饱和乙内酰脲的转化率均在90%以上,催化剂相对于底物的用量可大幅度降低.

Immobilization of Raney-Ni with Magnetic Material and Its Application

Raney-Ni catalyst is a useful catalyst in the preparation of fine chemicals because of its low price and high activity, but its activity is quickly lost when it is used repeatedly. According to the analysis of the SEM photos and particle size distribution, the main reasons for the quick loss of the Raney-Ni catalyst activity were the catalyst pulverization and loss, and the fusing of nickel micro-crystals at active sites in hydrogenation process. For increasing the catalyst reused time and reducing the catalyst loss, the magnetic material KF-610 was put into the reactor. During 20-batch hydrogenation, the conversion of 5-benzyl hydantoin, 5-(p-hydroxyl) benzyl hydantoin and 5-(indol-3-methyl)-hydantoin was over 90%, and the loss of the Raney-Ni catalyst was reduced to a great extent.