Speciation Characterization and Environmental Stability of Arsenic in Arsenic-Containing Copper Slag Tailing

Mu You; Yunhu Hu; Chuncai Zhou; Guijian Liu

doi:10.3390/molecules29071502

Speciation Characterization and Environmental Stability of Arsenic in Arsenic-Containing Copper Slag Tailing

Molecules. 2024 Mar 27;29(7):1502. doi: 10.3390/molecules29071502.

Authors

Mu You¹, Yunhu Hu², Chuncai Zhou³, Guijian Liu⁴

Affiliations

¹ School of Biology Engineering, Huainan Normal University, Huainan 232001, China.
² School of Chemistry and Materials Engineering, Huainan Normal University, Huainan 232001, China.
³ School of Resources and Environmental Engineering, Hefei University of Technology, No. 193, Road Tunxi, Hefei 230009, China.
⁴ School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.

Abstract

The increasing presence of arsenic-containing impurities within Cu ores can adversely affect the smelting process and aggravate the environmental impact of slag tailing. This study investigates the geochemical, mineralogical, and chemical speciation characteristics to better understand the association and environmental stability of metal(loid)s in copper slag tailing. The results indicate that the predominant chemical compositions of the selected slag tailing are Fe₂O₃ (54.8%) and SiO₂ (28.1%). These tailings exhibit potential for multi-elemental contamination due to elevated concentrations of environmentally sensitive elements. Mineral phases identified within the slag tailings include silicate (fayalite), oxides (magnetite and hematite), and sulfides (galena, sphalerite, arsenopyrite, and chalcopyrite). The consistent presence of silicate, iron, arsenic, and oxygen in the elemental distribution suggests the existence of arsenic within silicate minerals in the form of Si-Fe-As-O phases. Additionally, arsenic shows association with sulfide minerals and oxides. The percentages of arsenite (As(III)) and arsenate (As(V)) within the selected slag tailings are 59.4% and 40.6%, respectively. While the slag tailings are deemed non-hazardous due to the minimal amounts of toxic elements in leachates, proper disposal measures should be taken due to the elevated carbonate-bound levels of As and Cu present in these tailings.

Keywords: arsenic; chemical speciation; copper slag tailing; environmental mobility; mineralogy.

Grants and funding

This work was financially supported by the Collaborative Innovation Project of Anhui Province (GXXT-2023-018), the scientific research project of Anhui Provincial Department of Education (kj2021A0958, KJ2021A0964), the Key Program for Research and Technology Development of Anhui Province (No. 2023t07020006), the Postdoctoral Science Foundation of Anhui Province (No. 2020B438), and the scientific research project of Huainan Normal University (2022XJZD034).