Browsing by Subject "Hydrometallurgy"

Now showing 1 - 5 of 5
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    Characterization of Residue from the Pressure Oxidation Leaching of Bulk Copper-Nickel Sulfides from the Duluth Gabbro
    (University of Minnesota Duluth, 1999) Benner, Blair R; Niles, Harlan B
    The copper-nickel bearing material in the Duluth Gabbro represent a potentially significant reserve of copper and nickel with lesser amounts of cobalt and platinum group elements (PGEs). To help promote the development of this resource, the Coleraine Minerals Research Laboratory (CMRL) has conducted a series of investigations into methods of processing the material. A bulk sulfide flotation process followed by oxidation pressure leaching resulted in high extractions (>98 %) of the copper and nickel in the flotation concentrate. During the leaching, the iron in the flotation concentrate leaches and precipitates as either hematite (crystalline or amorphous) or as a basic iron sulfate (jarosite). The leaching should also leave the PGEs in the residue. If the hematite was present as a crystalline material, then if may be possible to recover a high grade iron product from the residue. If any PGE minerals could be found, then it may be possible to develop a method to recover and concentrate the PGEs. The Minnesota DNA through the Minerals Coordinating Committee funded the current study. The purpose of the research was to characterize the leach residue as to the iron bearing material and to determine if any PGE minerals could be found either by X-ray diffraction (XRD) or by electron microprobe analysis.
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    Extraction Metallurgy of Copper from Chalcopyrite Concentrates without Sulfuric Acid Generation via Chlorination - III. Integration of Gaseous Chlorination and Selective Oxidation
    (University of Minnesota Duluth, 1999) Iwasaki, Iwao; Tamagawa, T.; Fu, N. X; Kobayashi, M
    A 3-stage fluidizing bed process of chlorination, selective oxidation and sulfur chloride conversion was tested for processing of a chalcopyrite concentrate. It was found that the use of excess oxygen was essential to a stable operation in the oxidation reactor. The oxygen-excess gas will inevitably cause the oxidation of the sulfide concentrate in the chlorination and sulfur chloride conversion reactors. A new flowsheet is proposed to separate the chlorination and the selective oxidation steps with separate flow paths of the fluidizing gases, thereby preventing the passage of oxygen-excess gas in the chlorination and sulfur chloride conversion reactors. The feasibility of the proposed flowsheet was demonstrated in a laboratory-scale fluidizing bed setup.
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    Extraction of Copper from Chalcopyrite Concentrates without Sulfuric Acid Generation via Chlorination - I. Gaseous Chlorination of Sulfide Concentrates
    (University of Minnesota Duluth, 2000) Iwasaki, Iwao; Tamagawa, T.; Tabaian, S. H; Fu, N. X; Kobayashi, M
    A gaseous chlorination process for hydrometallurgical treatment of a chalcopyrite concentrate was investigated. The overall process is visualized to consist of low temperature chlorination-selective oxidation, followed · by aqueous chloride leaching and SX-EW for producing electrolytic copper, elemental sulfur and ferric oxide. In this article, the chlorination phase of the process is described. Initially, the chlorination behavior of chalcopyrite-concentrate micro-pellets was investigated using a small batch-type fluidized bed reactor. The optimum conditions thereby established were used in continuous chlorination tests. The chlorinated products thus prepared were used in the selective oxidation phase of the investigation.
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    Extraction of Copper from Chalcopyrite Concentrates without Sulfuric Acid Generation via Chlorination - II. Selective Oxidation of Chlorinated Products
    (University of Minnesota Duluth, 1999) Iwasaki, Iwao; Tamagawa, T.; Fu, N. X; Kobayashi, M
    A low temperature chlorination-selective oxidation, followed by aqueous chloride leaching and SX-EW for producing electrolytic copper, elemental sulfur and ferric oxide was investigated for hydrometallurgical processing of a chalcopyrite concentrate. In this article, the selective oxidation phase of the process is described. The selective oxidation requires a temperature well above the CuCl-FeCl3 eutectic points. The test procedure was developed with a batch reactor and then tested with a continuous reactor. The process was initiated by adding small amounts of chlorinated samples to a fluidizing bed of dead-roasted sulfide concentrate micro-pellets. The selectively oxidized samples thus prepared were shown to fully dissolve copper, while virtually all the iron remained undissolved.
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    Metallurgical Testing of Copper-Nickel Bearing Material from the Duluth Gabbro Progress Summary
    (University of Minnesota Duluth, 1998-06) Benner, Blair R
    This report summarizes the progress of metallurgical testing of copper-nickel bearing material from the Duluth gabbro to date and outlines the plan for the ongoing test program being funded under the University of Minnesota Permanent Trust Fund (PUTF).