氧化钨还原过程及机理研究

HYDROGEN REDUCING PROCESS AND MECHANISM OF TUNGSTEN OXIDE

利用X射线衍射仪、扫描电镜和比表面仪研究了WO3还原成W粉过程中的相结构、粉末形貌和粒度的演变过程及机理。结果表明WO3在还原过程中依次转变为WO2.90、WO2.72、WO2,最终被还原成W。在WO3氢还原成W粉的过程中,WO3具有的平滑规则六面体形貌会转变为粗糙六面体,并随着还原过程进行,较大的二次颗粒分解成小颗粒。在WO3氢还原成WO2.90和WO2.72的过程中,粉末的比表面积不断增大,粉末粒度不断减小,但在WO2.72还原为WO2和WO2还原为W的过程中,粉末比表面减小,粉末的粒度不断增大。

The phase structure, morphology and particle size evolutions of tungsten oxide reduced by hydrogen were studied by X-ray diffractometer, scanning electron microscope and specific surface area meter. It is shown that the phase structure evolution is WO3 WO2.90- WO2. 72-WO2-W. The surface morphology of powder changes from a smooth to a rough particle and eventually the bigger secondary particles turn to several smaller particles. The specif- ic surface area of the powder increases during WO3 reducing to WO290-WO2.72, while specific surface area of the powder decrease when WO2.72 reducing to WO2 and WO2 reducing to W.