球形三氧化钼还原产物形貌  

Reduction product morphology of the spherical molybdenum trioxide

作　　者：杨秦莉[1] 庄飞[1] 席莎[1] 卜春阳[1] 崔玉青[1] 何凯[1] YANG Qin-li;ZHUANG Fei;XI Sha;BU Chun-yang;CUI Yu-qing;HE Kai(Jinduicheng Molybdenum Co.,Ltd.,Xi'an 710077,China)

机构地区：[1]金堆城钼业股份有限公司,西安710077

出　　处：《粉末冶金技术》2021年第3期245-250,共6页Powder Metallurgy Technology

基　　金：国家重点研发计划专项资助项目(2017YFB0305600)。

摘　　要：通过两段氢气还原实验研究球形三氧化钼还原得到MoO_(2)和Mo粉的显微形貌。结果表明:经一段还原后球形三氧化钼(β-MoO_(3))先变成α-MoO_(3),再生成立方形的γ-Mo_4O_(11),最后形成α-MoO_(2);经二段还原得到Mo粉。MoO_(2)形貌受还原温度和还原气氛影响较大,还原温度较低或者在还原气氛中引入水分时,MoO_(2)为松散、细小的不规则形貌;还原温度较高或者还原气氛为大流量的干氢时,MoO_(2)为薄片状,易板结。超细Mo粉的形貌主要受还原温度、水蒸汽分压和氢气分压的影响,还原温度低或者氢气流量较小,应尽量使水蒸汽分压和氢气分压的比值接近平衡常数,可得到大小均匀、分散的超细钼粉。The morphology of MoO_(2) and Mo powders prepared by the two-stage hydrogen reduction experiment of the spherical molybdenum trioxide powders was studied.The results show that,the spherical molybdenum trioxide(β-MoO_(3))is transformed intoα-MoO3 firstly,and then the squareγ-Mo4O11 is regenerated to formα-MoO2 in first stage hydrogen reduction;Molybdenum powders are obtained in second stage hydrogen reduction.The morphology of MoO_(2) is greatly affected by the reduction temperature and reduction atmosphere,the MoO_(2) powders with fine and loose irregular morphology are obtained at low reduction temperature or by importing the water vapor into the reduction atmosphere;the MoO_(2) powders with flake and hardened are formed at the higher reduction temperature or in the dry hydrogen with large flow.The morphology of ultrafine Mo powders is mainly affected by the reduction temperature,the water vapor partial pressure,and the hydrogen partial pressure.When the reduction temperature is low or the hydrogen flow rate is small,the ratio of the water vapor partial pressure and the hydrogen partial pressure should be close to the equilibrium constant as far as possible,and the uniform and dispersed ultra-fine molybdenum powders can be obtained.

关 键 词：三氧化钼 氢气还原 超细钼粉 分压 

分 类 号：TG142.71[一般工业技术—材料科学与工程]