钨酸钠与天然土状石墨在高温氩气氛围中的转化过程

以Na_2WO_4为钨源,天然土状石墨为碳源,研究二者在高温氩气气氛下的转化过程及规律,利用X射线衍射(XRD)、扫描电子显微镜(SEM)及电子能谱(EDS)对产物进行分析。结果表明,Na_2WO_4与石墨的混合样品在氩气气氛下经高温处理,可以生成不同的碳钨化合物。首先,石墨与Na_2WO_4在接触界面发生还原反应,将Na_2WO_4还原为α-W2C和β-W2C;然后,随着石墨增多,当Na_2WO_4与石墨的质量比小于1:1时,石墨开始将α-W2C还原为α-WC,直至Na_2WO_4与石墨的质量比为1:5时,石墨可以将α-W2C完全转化为α-WC。

Transformation Process of Sodium Tungstata and Natural Graphite in Argon Atmosphere at High Temperature

Using sodium tungstate as tungsten source, natural soil shaped graphite as carbon source, an experiment is provided for researching the transformation process and rules of them in argon atmosphere at high temperature. The final products are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), etc. The result shows that the mixed samples of sodium tungstate and graphite can generate different tungsten carbon compounds in an argon atmosphere with heat treatment. First, reduction reaction occurs between mixed graphite and sodium tungstate dihydrate at the reaction interface, reducing sodium tungstate dihydrate toα-W2C andβ-W2C. Second, when the mass ratio of Na2WO4:C is less than 1:1, reduction ofα-W2C toα-WC occurs, till the mass ratio was 1:5, andα-W2C can be reduced toα-WC completely.