List of Articles Jarosite

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  1 - The effect of various parameters on the Jarosite formation in bioleaching of Sarcheshmeh copper mine sulfide ores
  Bahman Nazari Hadi Hani Esmaeil Jorjani Zahra Manafi
  Abstract: Background and Objective: Jarosite is one of the limiting factors for recovery of copper from copper sulfide minerals. This study aimed to evaluate the influence of concentration of ferrous sulfate, pH and temperature on the jarosite formation during the sulf More

  Abstract: Background and Objective: Jarosite is one of the limiting factors for recovery of copper from copper sulfide minerals. This study aimed to evaluate the influence of concentration of ferrous sulfate, pH and temperature on the jarosite formation during the sulfide ore bioleaching of Sarcheshmeh copper mine. Material and Methods: In this study, samples were collected from the depot crushing heap bioleaching site of Sarcheshmeh Copper Mine. The bioleaching experiments were performed in 500 ml flasks, containing 10% solids of sulfide ore  (w/v), pulp (200 ml), the 9K culture medium, bacteriainoculation (10% v/v of Acidithiobacillus ferrooxidans). The flask were shaked at 130 rpm throughout incubation. Results: Our results showed that increase in pH and concentration of ferrous sulfate facilitate rate of ferric iron precipitation. Maximum precipitation rate of ferric was achieved in 50 g/l of sulfate concentration, temperature 32 ° C and pH 2/2. According to XRD and FTIR analysis of Bioleaching residue, the produced ferric precipitations are often potassium and ammonium jarosite. Conclusion: With regard to the optimal conditions in this study in terms of pH, temperature and concentration of ferrous sulfate it is possible to regulate Jarosite formation through bioleaching process and to increase the production of copper efficiency from copper sulfide ores. Manuscript profile
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  2 - The catalytic activity of biological seeds and Acidithiobacillus ferrooxidans on the process of ammonium jarosite
  Nasim Eftekhari Mohammad Kargar Farokh Rokhbakhsh Zamin Nahid Rastakhiz Zahra Manafi
  Background & Objectives: Ferric iron that commonly exists in the leaching solution needs to be removed before the recovery of copper bioleaching using methods such as jarosite seed. The objective of this study was to investigate the catalytic performance of biologic More

  Background & Objectives: Ferric iron that commonly exists in the leaching solution needs to be removed before the recovery of copper bioleaching using methods such as jarosite seed. The objective of this study was to investigate the catalytic performance of biological seeds and Acidithiobacillus ferrooxidans in the process of jarosite formation via the biosynthesis process. Materials & Methods: Acidithiobacillus ferrooxidans was first grown in 9K medium. Jarosite seeds were synthesized using this bacterium. Then the effect of the biological activity of different seeds (5, 10 g/L) on jarosite formation was investigated. The type of jarosites synthesized was identified by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and scanning electron microscope (SEM) analysis. Meantime, the morphologies of jarosite crystals were studied. Results: The FTIR and XRD results showed that biosynthetic jarosite seeds are ammonium jarosite type. The amount of jarosite increased with increasing seed concentration and the induction time of precipitation decreased. The pH and Eh of culture medium with increasing seed decreased. Bacterial growth also decreased in the presence of jarosite seeds compared to medium without biological seeds. According to the results of SEM, The morphologies of ammonium jarosite crystals were significantly affected by the jarosite seeds. The jarosite crystals were precipitated with the presence of seeds that had a smooth, uniform, and larger surface than non- seeding jarosite. Conclusion: The results showed that the precipitation process of jarosite is more complete with biological seeds. The results of this study can improve the efficiency of the iron removal process in copper bioleaching and reduce production costs. Manuscript profile