摘要
硬质合金在机械制造等领域应用广泛,产生的硬质合金废料逐年增加,对硬质合金废料进行回收有利于节约资源、保护环境。采用循环伏安技术考察NaCl⁃KCl⁃Na_(2)WO_(4)熔盐体系中W(Ⅵ)的电化学行为,利用扫描电镜及X射线衍射技术研究电解电压对硬质合金废料阳极溶解形貌及组织结构变化的影响。结果表明:W(Ⅵ)在NaCl⁃KCl⁃Na_(2)WO_(4)熔盐体系中的电化学还原过程是准可逆的,反应受扩散控制,750℃时扩散系数为6.252×10^(-5)cm^(2)·s^(-1)。随着电解电压的增大,硬质合金废料表面形貌由颗粒团絮多孔状转变为蜂窝状,随后表面出现黑色块状物质。通过控制电解电压可以选择性分离回收硬质合金废料中的钨、钴金属,硬质合金废料中的钛优先于钨溶解,增大电压,更换阴极电解可得到纯钨产品。
Cemented carbide is widely used,prodcing an increasing number of waste materials.Therefore,the recycling of cemented carbide waste is conducive to saving resources and protecting the environment.The electrochemical behaviour of W(Ⅵ)in the NaCl-KCl-Na_(2)WO_(4)molten salt system was investigated by cyclic voltammetry(CV).The effect of electrolytic voltage on the morphology and microstructure of anodic dissolved alloy waste were studied by SEM and XRD.The results show that the electrochemical reduction process of W(Ⅵ)in the NaCl-KCl-Na_(2)WO_(4)molten salt system is quasi-reversible and controlled by diffusion.The diffusion coefficient is 6.252×10^(-5)cm^(2)·s^(-1)at 750℃.With the increase of electrolysis voltage,the surface morphology of cemented carbide waste changed from granular flocculent porous state to honeycomb,and then black lump-like substances appeared on the surface.The tungsten and cobalt metal in the cemented carbide scrap can be selectively separated and recycled by controlling the electrolysis voltage.The cobalt in the cemented carbide scrap is preferentially dissolved with tungsten,and changing cathode electrolysis by increasing voltage can refine pure tungsten products.
作者
李亮星
朱志城
贾孟熹
黄茜琳
LI Liangxing;ZHU Zhicheng;JIA Mengxi;HUANG Xilin(School of Energy and Mechanical Engineering,Jiangxi University of Science and Technology,Nanchang 330013,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第S01期448-453,共6页
Materials Reports
基金
江西省自然科学基金(20192BAB206019)
江西省教育厅科学技术研究项目(GJJ180449)
关键词
硬质合金废料
资源回收
钨
熔盐电解
电化学行为
cemented carbide scrap
resource recovery
tungsten
molten salt electrolysis
electrochemical behavior
