V2O5碳热还原合成碳化钒粉末的反应过程  

Reaction process of synthesizing vanadium carbide powder by vanadium pentoxide carbothermal reduction

作　　者：姜中涛[1,2] 刘颖[2] 陈巧旺[1] 夸力[1] 

机构地区：[1]重庆文理学院材料交叉学科研究中心,重庆市高校微纳米材料工程与技术重点实验室,重庆402168 [2]四川大学材料科学与工程学院,成都610065

出　　处：《粉末冶金技术》2012年第1期40-45,共6页Powder Metallurgy Technology

基　　金：重庆市自然科学基金计划重点项目(2010YZ0009);重庆市教委科学技术研究项目(KJ111212);重庆市高校创新团队建设计划培育团队资助项目(201042)

摘　　要：为了实现小批量连续化制备碳化钒粉末,以工业级V2O5和纳米炭黑为原料,利用碳热还原法,在常压下碳管炉中得到了V8C7。通过X射线衍射仪(XRD)、扫描电镜(SEM),分析了合成过程。结果表明:在较低的温度下,纳米炭黑将V2O5还原为VO2;随着合成温度的升高,还原为更低价的V2O3,但没有VO生成;接着发生碳化反应,生成VC1-x、V8C7,合成的各阶段相互重叠;在合成过程中,试样的显微组织因物相不同而有所不同,生成的钒氧化物为炭黑附着的颗粒状大团聚体,VC1-x粉末颗粒呈类球形,但大小不均匀;随着温度升高,合成的最终产物V8C7粉末颗粒呈球形或类球形,大小均匀,粒度为1μm左右;还原碳化过程中,产生的气体有CO、CO2。V8C7 vanadium carbide powder was prepared in small batch with industrial V205 and nanometer carbon powder as raw materials in graphite furnace by carbothermal reduction method. Reaction product was analyzed by XRD and SEM. The mechanism of synthesis was analyzed. The results show that at lower temperature, V205 can be reduced to VO2 by nano -carbon black. V205 is reduced to V203 with increasing synthesis temperature. Then it is carbonized to VC1-x and V8C7 but there is no appearance of VO during the reducing reaction. The synthesis stages are overlapped. The microstructure of the sample changes with the synthesis temperatures. Vanadium oxide are agglomerated particles with carbon black attached, whereas VC1-x, is similar to spherical particle with uneven -size. As the temperature increases, the V8C7 powder become spherical or near- spherical particles with uniform -size of about lμm. Both CO and CO2 give off in the carbothermal reduction process.

关 键 词：碳化钒 还原/碳化 V2O5 

分 类 号：TQ455.47[化学工程—农药化工]