Scholarlink

<p>The present study investigated and optimized biogenic cyanide (bio-CN) production by using mine indigenous bacterial strains with the aim of extracting precious metals from Upper Group Two (UG-2) platinum group metals (PGM) ore. Among all the bacterial strains tested, under optimized conditions, <i>Pseudomonas brassicacearum</i> produced the highest bio-CN (14.1 ± 1&#xa0;mg/L) and was therefore used in subsequent experiments. The study examined glycine consumption during cyanogenesis, as well as the stability and speciation of bio-CN. The findings confirmed that while glycine was consumed during cyanogenesis, the produced bio-CN was not stable and decreased over time, transforming into different cyanide species. The dose–response analysis for <i>P. brassicacearum</i> showed EC<sub>50</sub> of 1785&#xa0;g/L and 107.9&#xa0;g/L against untreated and pre-treated PGM concentrate, respectively, suggesting higher toxicity for the latter. Two-step bioleaching of the pre-treated PGM concentrate showed extractions of 75.7, 18.7, 9.4, and 0.3% for Au, Pd, Rh, and Pt, respectively, at 10&#xa0;g/L pulp density. The findings on bio-cyanide stability and bio-CN speciation presented in this paper are novel contributions. This study has established a foundation for developing a complete bio-based approach to PGM bioprocessing from UG-2 ores.</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Optimizing Biogenic Cyanide Production Using Indigenous Cyanogenic Microorganisms for Bioleaching of Precious Metals

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年5月12日

查看全文
  • Anil Kumar,
  • Alan Shemi,
  • Liberty Chipise,
  • Clarence S. Yah,
  • Sanchia Moodley,
  • Sehliselo Ndlovu

摘要

The present study investigated and optimized biogenic cyanide (bio-CN) production by using mine indigenous bacterial strains with the aim of extracting precious metals from Upper Group Two (UG-2) platinum group metals (PGM) ore. Among all the bacterial strains tested, under optimized conditions, Pseudomonas brassicacearum produced the highest bio-CN (14.1 ± 1 mg/L) and was therefore used in subsequent experiments. The study examined glycine consumption during cyanogenesis, as well as the stability and speciation of bio-CN. The findings confirmed that while glycine was consumed during cyanogenesis, the produced bio-CN was not stable and decreased over time, transforming into different cyanide species. The dose–response analysis for P. brassicacearum showed EC50 of 1785 g/L and 107.9 g/L against untreated and pre-treated PGM concentrate, respectively, suggesting higher toxicity for the latter. Two-step bioleaching of the pre-treated PGM concentrate showed extractions of 75.7, 18.7, 9.4, and 0.3% for Au, Pd, Rh, and Pt, respectively, at 10 g/L pulp density. The findings on bio-cyanide stability and bio-CN speciation presented in this paper are novel contributions. This study has established a foundation for developing a complete bio-based approach to PGM bioprocessing from UG-2 ores.

Graphical Abstract