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JOM

, Volume 55, Issue 4, pp 37–40 | Cite as

Leaching platinum-group metals in a sulfuric acid/chloride solution

  • M. H. H. Mahmoud
Research Summary Precious Metals: Aqueous

Abstract

A leaching process was established based on the ability of platinum-group metals to form stable chloro-complexes in acidic chloride solutions. Industrial catalyst losses were examined for the recovery of platinum, palladium, and rhodium by leaching with a mixture of sulfuric acid and sodium chloride to avoid using aqua regia or autoclave conditions. Extraction of platinum and rhodium in 60% H2SO4 at 135°C steadily increased with increasing NaCl concentrations reaching 95% and 85%, respectively, at 0.1 M NaCl after two hours. By comparison, palladium was dissolved more quickly but also reached 85% under the same conditions. Extraction of each metal increased with temperatures up to 125°C but plateaued at higher temperatures. Similar behavior was observed with increasing H2SO4 concentrations up to 60%. More than 99% extraction of each metal was obtained after ten hours using 0.1 M NaCl and 60% H2SO4 at 125°C.

Keywords

Palladium Rhodium Platinum Group Metal Acidic Chloride Solution Unwashed Sample 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© TMS 2003

Authors and Affiliations

  • M. H. H. Mahmoud
    • 1
  1. 1.the Extractive Metallurgy DepartmentCentral Metallurgical R&D InstituteCairoEgypt

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