镍钼配比对镍钼氮化物结构和丙烷氨氧化反应性能的影响  

EFFECT OF Ni/Mo RATIO ON STRUCTURE OF Ni-Mo NITRIDE AND PROPANE AMMOXIDATION REACTION

作　　者：张惠民 Zhang Huimin(China Energy Group Corporation Ltd. ,Beijing 100011)

机构地区：[1]国家能源投资集团有限责任公司,北京100011

出　　处：《石油炼制与化工》2018年第6期56-60,共5页Petroleum Processing and Petrochemicals

基　　金：国家自然科学基金资助项目(20373043)

摘　　要：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,H_2-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Ni_2Mo_3N或定向合成γ-Mo_2N和Ni_2Mo_3N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-Mo_2N或Ni_2Mo_3N;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773K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 heptamolybdate.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 ammoxidation was tested.The experimental results showed that Ni2Mo3N or the mixture ofγ-Mo2N and Ni2Mo3N can be synthesized by controlling Ni/Mo atomic ratio.These results suggested that the synergetic effect betweenγ-Mo2N and Ni2Mo3N in the mixed Ni-Mo nitrides plays an important role in the process of propane ammoxidation.The mixed Ni-Mo nitride catalyst shows much higher catalytic activity and selectivity for ACN thanγ-Mo2N or Ni2Mo3N alone.The mixed NiMo nitride catalyst with 3/2of Ni/Mo atomic ratio showed the best catalytic performance for propane ammoxidation.At 773K,the conversion of propane is 75.0%,the selectivity and the yield of ACN are 38.6%and 28.95%,respectively.

关 键 词：镍钼配比 镍钼氮化物 催化剂 烷烃 氨氧化 

分 类 号：TQ226.61[化学工程—有机化工]