以钼酸铵和硝酸镍为原料,采用共沉淀法合成镍钼金属氧化物,再经过程序升温氮化反应合成镍钼双金属氮化物.利用XRD,Visible-Raman,FTIR,H2-TPR对镍钼氧化物及氮化物晶体结构及氧化还原性进行表征,并考察了丙烷在镍钼氮化物催化剂上的氨氧化反应性能.结果表明:通过控制化学试剂镍钼配比能够定向合成Ni2 Mo3 N或定向合成γ-Mo2 N和Ni2 Mo3 N两相共存的镍钼氮化物;两相共存的镍钼氮化物催化剂能够产生相互协同作用,有利于催化丙烷氨氧化反应,其催化活性和丙烯腈选择性明显优于单一晶相的 γ-Mo2 N或Ni2 Mo3 N;由镍钼摩尔比为3/2的化学试剂制得的镍钼氮化物催化剂表现出最优的催化性能,在773 K时丙烷转化率为75.0％,丙烯腈选择性为38.6％,产率为28.95％.%Ni-Mo oxide was prepared by co-precipitation of nickel nitrate and ammonium heptamolyb-date. Ni-Mo nitride catalysts were synthesized by temperature-programmed nitridation reaction of Ni-Mo oxide in a mixture of H2/N2. The structure and redox properties of the Ni-Mo oxide and corresponding nitride catalysts were characterized by XRD,visible-Raman,FT-IR,and H2-TPR. The catalytic performance for propane ammoxi-dation was tested. The experimental results showed that Ni2 Mo3 N or the mixture of γ-Mo2 N and Ni2 Mo3 N can be synthesized by controlling Ni/Mo atomic ratio. These results suggested that the synergetic effect betweenγ-Mo2 N and Ni2 Mo3 N in the mixed Ni-Mo nitrides plays an important role in the process of propane ammoxida-tion. The mixed Ni-Mo nitride catalyst shows much higher catalytic activity and selectivity for ACN thanγ-Mo2 N or Ni2 Mo3 N alone. The mixed NiMo nitride catalyst with 3/2 of Ni/Mo atomic ratio showed the best catalytic performance for propane ammoxidation. At 773 K,the conversion of propane is 75. 0％,the selectivity and the yield of ACN are 38. 6％ and 28. 95％,respectively.
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