RECOVERY OF TUNGSTEN AND MOLYBDENUM FROM TUNGSTEN SOLUTION CONTAINING MOLYBDENUM VALUES

摘要

A process is disclosed for recovering tungsten and molybdenum values from tungsten concentrates containing molybdenum in an amount at least about one-twentieth of the amount of contained WO3. The concentrate, generally a wolframite concentrate, is subjected to dissolution in hot NaOH solution to provide a pregnant liquor or solution containing tungsten and molybdenum values. The solution, after purification, is treated with a sulfide precipitation agent to precipitate MoS3 and some WS3 using a stoichiometric excess of a sulfide precipitating agent to produce a filtrate containing tungsten substantially free of molybdenum. The sulfide precipitate is dissolved in dilute NaOH solution and again precipitated using a stoichiometric deficient amount of the sulfide precipitating agent to produce a precipitate of MoS3 low in tungsten. The foregoing sulfide precipitation steps may be reversed.