焙烧-浸出法分离回收白合金中的有价金属  

Separation and recovery of valuable metals in white alloy by novel roasting-leaching method

作　　者：刘朝阳 姚健 王海 王佳东 高宣雯 李建中 刘朝孟 翟玉春 骆文彬 LIU Zhaoyang;YAO Jian;WANG Hai;WANG Jiadong;GAO Xuanwen;LI Jianzhong;LIU Zhaomeng;ZHAI Yuchun;LUO Wenbin(School of Metallurgy,Northeastern University,Shenyang 110167,China;Guangxi Yinyi Advanced Material Company Limited,Yulin 537000,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110167 [2]广西银亿新材料有限公司,广西玉林537000

出　　处：《中南大学学报（自然科学版）》2023年第2期518-528,共11页Journal of Central South University:Science and Technology

基　　金：“兴辽英才计划”青年拔尖人才基金资助项目(XLYC2007155);中央高校基本科研业务费资助项目(N2025018,N2025009)。

摘　　要：白合金是铜钴矿冶炼过程的中间产物,存在大量钴、铜、铁金属元素,其中酸性溶液中的铁、钴分离是白合金湿法回收的难点之一。采用焙烧-浸出法分离回收白合金酸浸生成的硫酸铁-硫酸钴混合溶液。通过设计单因素实验探索最佳工艺条件,采用X射线衍射(XRD)以及扫描电子显微镜(SEM)研究白合金有价金属分离过程中的物相变化。研究结果表明:在硫酸浓度为1.9 mol/L、浸出温度为90℃、浸出时间为60 min和液固比为5:1 (L/g)的最佳条件下,白合金中钴和铁的浸出率达到91.78%和98.67%,而铜在硫酸溶液中保持稳定的斜方蓝辉铜矿结构残留在滤渣(含铜渣)中;随后将滤液浓缩结晶得到水合硫酸铁-硫酸钴混合晶体,并在600℃下焙烧,使硫酸铁热分解成难溶于水的氧化铁,而硫酸钴保持稳定,经水溶浸出后测得钴、铁浸出率为98.5%和0.1%,达到理想分离效果;最后将含铜渣在450℃下焙烧,形成硫酸铜-氧化铜化合物,经过酸浸可完全回收有价金属铜。White alloy is the intermediate product of copper and cobalt smelting,in which there are a lot of valuable metals.The calcination-leaching method was used to separate and recover the valuable metals in the white alloy,and the influence of sulfuric acid concentration,liquid-solid ratio,leaching temperature,roasting temperature and roasting time on the leaching rate of Fe,Co and Cu in white alloy was mainly investigated.The results show that the leaching rates of cobalt and iron in the white alloy reach 91.78% and 98.67%,respectively,under the optimal conditions of sulfuric acid concentration of 1.9 mol/L,leaching temperature of 90℃,leaching time of 60 min and liquid-solid ratio of 5:1 (L/g).The copper remains in the residue with orthorhombic chalcocite structure (copper residue),and its leaching rate is only 0.62%.The hydrated composited Fe2(SO4)3-CoSO4is obtained after concentration of filtrate which is calcined at 600℃ for 180 min.Due to the difference in thermal decomposition temperature of CoSO4and Fe2(SO4)3,the Fe2(SO4)3in the mixed crystal is thermally decomposed into iron oxide which is insoluble in water,while cobalt sulfate remains stable.As a result,the leaching rates of cobalt and iron are 98.5% and 0.1%,respectively,in aqueous solution,achieving the satisfactory separation.Finally,the copper residue is calcined at 450℃to form CuSO4-CuO composite,and the copper can be recovered completely through sulfuric acid leaching.

关 键 词：白合金 选择性浸出 硫酸盐分解 硫酸化焙烧 酸浸 

分 类 号：TF816[冶金工程—有色金属冶金] TF811