REWAS 2013 pp 287-294 | Cite as

Cyanide and Copper Recovery from Barren Solution of the Merrill Crowe Process

  • José R. Parga
  • Jesús L. Valenzuela
  • J. A. Díaz


This paper is a brief overview of the role of inducing the nucleated precipitation of copper and cyanide in a flashtube serpentine reactor, using sodium sulfide as the precipitate and sulfuric acid as pH control. The results showed that pH had a great effect on copper cyanide removal efficiency and the optimum pH was about 3 to 3.5. At this pH value copper cyanide removal efficiency could be achieved above 97 and 99 %, when influent copper concentration ions were 650 and 900 ppm respectively. In this process the cyanide associated with the copper, zinc, iron cyanide complexes are released as HCN gas under strong acidic conditions, allowing it to be recycled back to the cyanidation process as free cyanide.


Cyanide recovery Copper recovery Precipitation copper 


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Copyright information

© TMS (The Minerals, Metals & Materials Society) 2013

Authors and Affiliations

  • José R. Parga
    • 1
  • Jesús L. Valenzuela
    • 2
  • J. A. Díaz
    • 1
  1. 1.Department of Metallurgy and Materials ScienceInstitute Technology of SaltilloSaltillo CoahuilaMéxico
  2. 2.Department of Chemical Engineering and MetallurgyUniversity of SonoraHermosilloMéxico

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