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›› 2013, Vol. 13 ›› Issue (4): 704-709.

• 材料工程专栏 • 上一篇    下一篇

V2O5制备VN的还原氮化机理

王安仁 陈立平 张庆春   

  1. 北京科技大学冶金与生态工程学院 北京科技大学冶金与生态工程学院 北京科技大学冶金与生态工程学院
  • 收稿日期:2013-05-17 修回日期:2013-06-08 出版日期:2013-08-20 发布日期:2013-08-20
  • 通讯作者: 陈立平

Carbothermal Reduction and Nitridation Mechanism of VN Prepared by V2O5

WANG An-ren CHEN Li-ping ZHANg Qing-chun   

  1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing
  • Received:2013-05-17 Revised:2013-06-08 Online:2013-08-20 Published:2013-08-20
  • Contact: CHEN Li-ping

摘要: 以V2O5粉末为原料,C粉末为还原剂,对碳热还原氮化法制备VN的机理进行研究,重点讨论了配碳量和温度对产物的影响. 结果表明,V2O5为逐级还原,存在直接和间接还原;配碳量(C/V2O5)为28%(w)时,产物氮含量最高;800~1000℃发生碳化反应生成VC1-x, 1000~1200℃同时发生碳化和氮化反应,主要生成V(C,N);温度超过1300℃, V(C,N)向VC1-x转化. 随温度升高,产物氮含量逐渐降低,钒含量逐渐升高,产物之间发生团聚甚至熔蚀形成球状,大部分颗粒粒径约为1 mm. 采用本工艺进行实际生产,产品氮含量>17%,钒含量为79%,碳含量<2%,表观密度约为3.5 g/cm3,符合国家标准.

关键词: 氮化钒, 还原, 氮化, 五氧化二钒, 热力学, 配碳量

Abstract: The reduction and nitridation mechanism for preparation of VN with V2O5 as raw material and carbon powder as reductant was studied, the effects of mass ratio of C to V2O5 and temperature were examined, and the products analyzed. The results show that the reduction of V2O5 is successive, and indirect reduction occurs along with direct reduction. When the mass ratio of C/V2O5 is 28%, the nitrogen content in products is maximum. From 800 to 1000℃, carbonization reaction takes place, and the product is VC1-x. From 1000 to 1200℃, carbonization and nitridation reactions take place simultaneously, and the main phase is V(C,N). When the temperature is higher than 1300℃, V(C,N) is transformed gradually into VC1-x with the increase of temperature, the nitrogen content decreases and the vanadium content increases, the products will agglomerate even fuse each other and are composed of spherical particles with the average diameter of 1 mm. Using the above process to prepare VN, the nitrogen content of products can reach more than 17%, vanadium content more than 79%, and carbon content less than 2%, and the apparent density is about 3.5 g/cm3 which accords with national standard.

Key words: vanadium nitride, reduction, nitridation, vanadium pentoxide, thermodynamics, mass ratio of C to V2O5

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