| 摘要 |
<p>A process for selectively removing oxidized metal impurities of one or more of the metals cobalt, zinc, nickel, and copper from a molybdenite concentrate comprises suspending the molybdenite concentrate in an aqueous solution containing at least about 10 grams per liter of ammonia and at least about 4 grams per liter of an ammonium salt and maintaining the suspension at a temperature of from about 25 DEG C to about 90 DEG C for a time sufficient for the aqueous solution to selectively leach at least a substantial portion of the impurities from the molybdenite concentrate. When the molybdenite concentrate contains nonoxidized metal impurities of such metals, e.g., copper sulfides, the impurities are converted to oxidized metal impurities in-situ in the suspension by contacting the suspension with an oxygen-containing gas, and the resulting oxidized metal impurities are leached from the molybdenum concentrate by the aqueous solution. The molybdenite concentrates can be further leached with an acidic brine solution or hydrochloric acid solution to remove lead or iron impurities respectively, therefrom.</p> |
