The Geochemical Interpretation of Phase Transform and Fe-leaching Efficiency for Pyrite by Microwave Energy and Ammonia Solution

마이크로웨이브 에너지에 의한 황철석의 상변환과 암모니아 용액에 의한 Fe-용출 효율에 관한 지구화학적 해석

  • Received : 2013.07.18
  • Accepted : 2013.09.26
  • Published : 2013.09.30


In order to effectively leach Fe from pyrite, the application of microwave energy and ammonia solution has been conducted. Pyrite transforms into hematite and pyrrhotite when treated with microwave radiation for 60 minutes, and in this time the highest amount of Fe was leached by the ammonia solution. Up to 99% of the Fe was leached when the experimental conditions were: 325-400 mesh particle size for the pyrite and 60 min. was the microwave exposure time. The ammonia leaching conditions were 0.3 M sulfuric acid, 2.0 M ammonium sulfate and 0.1 M hydrogen peroxide concentration. The pyrite, hematite, and pyrrhotite were not detected using XRD analysis from the solid-residues treated by the ammonia solution except for quartz.


microwave energy;pyrite;hematite;pyrrhotite;ammonia solution


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