Abstract: The degree of oxidation,composition and valence tstate of the reduced copper cata-lyst prepared by the reduction in the aqueous phase were examined by themal analysis,pow-der X-ray diffrection analysis and XPS measurements,The catalytic abilities,i.e,hydrationactivity of acrylonitrile and selectivity of acrylamide and ethylene cyanohydrin were decreasedobviously with increase of the degree of oxidation of the reduced catalyst Cu0 was found tobe the active component and Cu²⁺ and Cu⁺-the poisoning components. The results showed that a variety of active sites exists in the reduced copper catalystsurface and the oxidation of copper catalyst with dissolved oxygen in water was much morerapid thn tht with oxygen in gaseous phase.

Key words: acrylonitrile, acrylamide, copper catalyst, catalytic activity