Formation mechanism of zinc-doped fayalite (Fe2-xZnxSiO4) slag during copper smelting

Zhongbing Wang; Zongwen Zhao; Lifeng Zhang; Fansong Liu; Bing Peng; Liyuan Chai; Dachun Liu; Degang Liu; Tianyu Wang; Hui Liu; Yanjie Liang

doi:10.1016/j.jhazmat.2018.10.071

Formation mechanism of zinc-doped fayalite (Fe_2-xZn_xSiO₄) slag during copper smelting

J Hazard Mater. 2019 Feb 15:364:488-498. doi: 10.1016/j.jhazmat.2018.10.071. Epub 2018 Oct 23.

Authors

Zhongbing Wang¹, Zongwen Zhao¹, Lifeng Zhang¹, Fansong Liu¹, Bing Peng², Liyuan Chai², Dachun Liu³, Degang Liu¹, Tianyu Wang¹, Hui Liu⁴, Yanjie Liang⁵

Affiliations

¹ School of Metallurgy & Environment, Central South University, 410083, Changsha, Hunan, China.
² School of Metallurgy & Environment, Central South University, 410083, Changsha, Hunan, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, 410083, Changsha, Hunan, China.
³ The National Engineering Laboratory of Vacuum Metallurgy, Kunming University of Science and Technology, Kunming, 650093, China.
⁴ School of Metallurgy & Environment, Central South University, 410083, Changsha, Hunan, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, 410083, Changsha, Hunan, China. Electronic address: [email protected].
⁵ School of Metallurgy & Environment, Central South University, 410083, Changsha, Hunan, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, 410083, Changsha, Hunan, China. Electronic address: [email protected].

PMID: 30388632
DOI: 10.1016/j.jhazmat.2018.10.071

Abstract

The interactions between Fe₂SiO₄ and ZnO play an essential role in the recovery of zinc from copper slag. The dissolution and substitution mechanism of ZnO in fayalite were investigated by using TG-DSC, XRD, PPMS DynaCool, XPS, Mossbauer and SEM-EDS analyses and compared with MS calculation results. The results indicate that the dissolution and substitution are actually processes of the penetrating dissolution of Zn(II) ions that can be divided into three steps: 1) ZnO dissociates into Zn_1-yO and Zn(II) ions; 2) Zn(II) penetrates the gap of the octahedron outer layer to substitute Fe(II) sites in the internal structure of SiOFe(II) (M2) to form (Fe_2-x, Zn_x)SiO₄; 3) Fe(II) is forced to migrate to the surface of (Fe_2-x, Zn_x)SiO₄ to form (Zn_1-y, Fe(II)_y)O. These findings can be derived the occurrence state and distribution of zinc in copper slag theoretically.

Keywords: (Fe(2-x)Zn(x))SiO(4); Fayalite; Penetrating migration; Substitution mechanism; ZnO.

Publication types

Research Support, Non-U.S. Gov't