钨酸钠与天然土状石墨在高温氩气氛围中的转化过程  

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

作　　者：魏霖荫 传秀云[1] 黄杜斌[1] 苏双青[1] 金时运 WEI Linyin;CHUAN Xiuyun;HUANG Dubin;SU Shuangqing;JIN Shiyun(School of Earth and Space Sciences, Peking University, Beijing 100871)

机构地区：[1]北京大学地球与空间科学学院,北京100871

出　　处：《北京大学学报（自然科学版）》2017年第1期50-56,共7页Acta Scientiarum Naturalium Universitatis Pekinensis

基　　金：国家自然科学基金(51274015);国土资源部钨矿资源勘查与开发信息监测与分析项目(13GS03-01);国家重点基础研究发展计划(2014CB846000);北京大学开放测试基金(0000012321)资助

摘　　要：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。Using sodium tungstate as tungsten source,natural soil shaped graphite as carbon source,an experiment isprovided for researching the transformation process and rules of them in argon atmosphere at high temperature.The finalproducts 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 tungstencarbon compounds in an argon atmosphere with heat treatment.First,reduction reaction occurs between mixedgraphite 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 than1:1,reduction ofα-W2C toα-WC occurs,till the mass ratiowas1:5,andα-W2C can be reduced toα-WC completely.

关 键 词：石墨 Na2WO4 WC 高温处理 X射线衍射(XRD) 扫描电子显微镜(SEM) 电子能谱(EDS) 

分 类 号：TQ136.13[化学工程—无机化工]