**Development of a Sustainable Process for Complex Sulfide Ores Containing Anglesite: Effect of Anglesite on Sphalerite Floatability, Enhanced Depression of Sphalerite by Extracting Anglesite, and Recovery of Extracted Pb2+ as Zero-Valent Pb by Cementation Using Zero-Valent Fe**

**Kosei Aikawa 1,\* , Mayumi Ito <sup>2</sup> , Atsuhiro Kusano <sup>1</sup> , Sanghee Jeon <sup>2</sup> , Ilhwan Park <sup>2</sup> and Naoki Hiroyoshi <sup>2</sup>**


**Citation:** Aikawa, K.; Ito, M.; Kusano, A.; Jeon, S.; Park, I.; Hiroyoshi, N. Development of a Sustainable Process for Complex Sulfide Ores Containing Anglesite: Effect of Anglesite on Sphalerite Floatability, Enhanced Depression of Sphalerite by Extracting Anglesite, and Recovery of Extracted Pb2+ as Zero-Valent Pb by Cementation Using Zero-Valent Fe. *Minerals* **2022**, *12*, 723. https://doi.org/10.3390/ min12060723

Academic Editor: Hyunjung Kim

Received: 26 April 2022 Accepted: 3 June 2022 Published: 6 June 2022

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**Abstract:** The presence of anglesite (PbSO<sup>4</sup> ) in complex sulfide ores negatively affects the separation of Cu-Pb sulfides and sphalerite (ZnS) due to lead activation, and PbSO<sup>4</sup> rejected to tailings dams contaminates the surrounding environment with lead. To address these problems, this study investigated the application of ethylene diamine tetra acetic acid (EDTA) pretreatment extracting PbSO<sup>4</sup> to ZnS flotation and the recovery of the extracted Pb2+ as zero-valent Pb by cementation using zero-valent iron (ZVI). The application of EDTA pretreatment could extract ~99.8% of PbSO<sup>4</sup> , thus depressing ZnS floatability from 82% to 30%. In addition, cementation using ZVI could recover ~99.7% of Pb2+ from the leachate of EDTA pretreatment.

**Keywords:** flotation; complex sulfide ores; sphalerite; anglesite; extraction; cementation
