The Combined Effects of Galvanic Interaction and Silicate Addition on the Oxidative Dissolution of Pyrite: Implications for Acid and Metalliferous Drainage Control

Gujie Qian, Rong Fan, Michael Short, Russell Schumann, Allan Pring, Andrea Gerson

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)

Abstract

The aim of this study was to determine the combined effect of galvanic interaction and silicate addition on the dissolution of pyrite, the major contributor to acid and metalliferous drainage (AMD). Single (pyrite, sphalerite, and galena)- A nd bi-sulfide (pyrite-sphalerite and pyrite-galena) batch dissolution experiments were carried out with addition of 0.8 mM dissolved silicate for comparison to previously published data. The pyrite dissolution rate was reduced by 98% upon silicate addition at pH 7.4 with little effect at pH 3.0 and 5.0. The effect of galvanic interaction on reducing pyrite dissolution decreased with increasing pH and was greater in the presence of sphalerite than galena. In contrast, the effect of silicate addition increased with increasing pH and was greater in the presence of galena than sphalerite. The greatest combined effect was at pH 7.4, with <0.1% of pyrite leached in both bi-sulfide systems. Silicate addition also significantly reduced the dissolution of sphalerite or galena (by 10-44%, except at pH 3 for the pyrite-sphalerite system). These results suggest that silicate addition, for reducing both pyrite dissolution and metalliferous drainage, may be applicable at a broad pH in mixed sulfide systems.

Original languageEnglish
Pages (from-to)11922-11931
Number of pages10
JournalEnvironmental Science and Technology
Volume53
Issue number20
DOIs
Publication statusPublished - 15 Oct 2019

Keywords

  • Galvanic interaction
  • Silicate dissolution
  • Pyrite
  • Acid and Metalliferous Drainage

Fingerprint

Dive into the research topics of 'The Combined Effects of Galvanic Interaction and Silicate Addition on the Oxidative Dissolution of Pyrite: Implications for Acid and Metalliferous Drainage Control'. Together they form a unique fingerprint.

Cite this