雷尼镍活性本质的探讨  

A probe into the mechanism for activity of Raney-nickel catalysts

作　　者：夏少武[1] 刘红天[1] 赵纯洁[1] 

机构地区：[1]青岛科技大学应用化学系,山东青岛266042

出　　处：《工业催化》2003年第2期36-41,共6页Industrial Catalysis

摘　　要：本文认为雷尼镍(Raneynickel)催化剂产生活性的原因是因为表面缺陷部位存在活性中心,原始合金相组成和制备方法影响缺陷的类型,从而可形成不同类型的活性中心。对于普通加氢反应,相对应的活性中心将氢分子活化为弱吸附的线性Ni H表面物种,使其参与加氢反应;对于不对称加氢反应,前手性底物吸附在手性活性中心之上,使其构型稳定,从而生成单一对映体。The causes behind activity of Raney nickel were discussed in this paper. It is pointed out that activity of Raney nickel attributes to existence of defects on the surface. Types of the defects and hence the active sites formed are affected by composition of starting NiAl alloy and preparation methods. For normal hydrogenation reactions, hydrogen molecules are activated by corresponding active sites to form NiH linear surface species with weak absorption, which participate in the reaction; for enantiodifferentiating hydrogenation, prochiral substrate is absorbed on the chiral active sites which stabilizes the configuration to form single enantiomorphs.

关 键 词：雷尼镍 活性中心 缺陷 手性催化剂 

分 类 号：O643.361[理学—物理化学] TQ426.99[理学—化学]