摘要
砷碱渣是锑冶炼行业产生的固体废渣,对环境和人体健康构成严重威胁。目前,常见的砷碱渣湿法处理工艺不仅有价元素回收率低、砷碱分离不完全,还会产生砷碱混合盐,无法实现砷碱渣完全无害化处理。为解决这些问题,本文采用氧化水浸处理砷碱渣,实现了砷和锑的分离,砷、锑的浸出率分别为91.79%和0.62%,浸出渣可返回锑冶炼系统回收锑。通过碳热还原直接从砷碱混合盐(砷碱液蒸发结晶产物)中分离砷和碱,98.3%的砷可被脱除并制备成具有商业价值的无毒高纯金属砷,纯度达到99.9%;碱可从还原后渣中实现回收,良好地实现了砷碱混合盐的无害化和资源化处理。通过热力学、物相和砷价态分析研究了砷还原路径及挥发机理。
Arsenic-alkali residue is a solid waste produced by the antimony smelting industry,which can pose a threat to the environment and human health.The common wet treatment process of arsenic-alkali residue has a low recovery of valuable elements,incomplete separation of arsenic and alkali,and also produces arsenic-alkali mixed salt,which cannot realize the completely harmless treatment of arsenic-alkali residue.In order to solve these problems,the oxidative water leaching process was used to treat arsenic-alkali residue,which realized the separation of arsenic and antimony.The leaching efficiencies of arsenic and antimony were 91.79%and 0.62%,respectively.The leaching residue could be returned to the antimony smelting system to recover antimony.Then the arsenic and alkali were directly separated from the arsenic-alkali mixed salt by carbothermal reduction,and 98.3%of arsenic was removed,and the non-toxic metallic arsenic with 99.9%purity was prepared.The alkali could be recovered from the slag after reduction,which solved the problem of harmless and recycling treatment of arsenic-alkali mixed salts.The mechanism of arsenic reduction pathway was studied through thermodynamic,phase,and arsenic valence state analyses.
作者
龚傲
吴选高
李金辉
王瑞祥
徐家聪
温盛汇
易勤
田磊
徐志峰
GONG Ao;WU Xuan-gao;LI Jin-hui;WANG Rui-xiang;XU Jia-cong;WEN Sheng-hui;YI Qin;TIAN Lei;XU Zhi-feng(Institute of Green Metallurgy and Process Intensification,Jiangxi University of Science and Technology,Ganzhou 341000,China;Ganzhou Engineering Technology Research Center of Green Metallurgy and Process Intensification,Ganzhou 341000,China;Jiangxi College of Applied Technology,Ganzhou 341000,China)
基金
Project(2019YFC1907405) supported by the National Key R&D Program of China
Projects(52064021,52074136,51974140,52064018) supported by the National Natural Science Foundation of China
Project(20204BCJL23031) supported by the Jiangxi Provincial Cultivation Program for Academic and Technical Leaders of Major Subjects,China
Project(20202ACB213002) supported by the Jiangxi Province Science Fund for Distinguished Young Scholars,China
Project(2019KY09) supported by the Merit-based Postdoctoral Research in Jiangxi Province,China
Project(JXUSTQJBJ2020004) supported by the Program of Qingjiang Excellent Young Talents,Jiangxi University of Science and Technology,China
Project(20212ACB204015) supported by the Key Projects of Jiangxi Key R&D Plan,China。
关键词
砷碱渣
资源回收
分离
碳热还原
金属砷
arsenic-alkali residue
resource recovery
separation
carbothermal reduction
metallic arsenic