锌粉还原五氧化二钒制备三氧化二钒粉体

Preparation of Vanadium Trioxides Powder by Reduction of Vanadium Pentoxides with Powdery Zinc

以V_(2)O_(5)为钒源,Zn粉为还原剂,采用化学法制备V(OH)_(3)前驱体,通过热分解前驱体制备V_(2)O_(3)粉体。探讨了pH值、前驱体沉淀时间和温度、还原时间和温度对V_(2)O_(3)粉体纯度和产率的影响。通过TG-DTA、化学滴定、XRD、SEM分析了V(OH)_(3)前驱体分解温度、V_(2)O_(3)产品的纯度、物相和形貌。结果表明:在约463℃前驱体V(OH)_(3)开始分解,在pH值为5.2、前驱体沉淀时间为60 min、前驱体沉淀温度为40℃、还原时间10 min、还原温度20℃的条件下,V_(2)O_(3)粉体的纯度可以达到98.8%,产率为88.5%,所制备的产物是一种以棒状为主,结晶性好、纯度高的黑色晶体粉末。

V(OH)_(3) precursor was prepared by chemical method using vanadium pentoxides(V_(2)O_(5))as raw materials and zinc powder(Zn)as the reductant.Then,vanadium trioxides(V_(2)O_(3))powder was prepared by thermal decomposition of the precursor.The effects of pH value,precursor precipitation time and temperature,the reduction time and temperature on the mass fraction and yield of V_(2)O_(3) powder were studied systematically.The decomposition temperature of V(OH)_(3) precursor was analyzed by TG-DTA.The purity,phase and morphology of V_(2)O_(3) were characterized by chemical titration,XRD and SEM respectively.The results showed that V(OH)_(3) began to decompose at about 463℃and when the pH was 5.2,the sedimentation time of precursor was 60 minutes,the temperature of precursor precipitation was 40℃,reduction time was 10 minutes and reduction temperature was 20℃respectively,the mass fraction of V_(2)O_(3) could reach 98.8%and the yield was 88.5%.The rod-like product with good crystallinity and high purity is a black crystal powder.