Process of recovering high purity tungsten compositions from tungsten-bearing ores

Claim 1

A PROCESS OF RECOVERING TUNGSTEN VALUES FROM A TUNGSTEN-BEARING ORE, WHICH COMPRISES TREATING THE ORE WITH SODIUM CARBONATE AND HEAT FOR CONVERTING TUNGSTEN COMPOUNDS IN THE ORE TO SODIUM TUNGSTATE, LEACHING THE ORE WITH WATER TO DISSOLVE THE SODIUM TUNGSTATE, REMOVING THE INSOLUBLE RESIDUE FROM THE AQUEOUS LEACH LIQUOR BY FILTRATION, ADDING A SOLUBLE ALKALI SULFIDE SALT TO THE LEACH LIQUOR, ACIDIFYING SAID LEACH LIQUOR WITH SULFURIC ACID TO A PH OF AT LEAST 3, HEATING THE ACIDIFIED LIQUOR TO 80*C., SEPARATING INSOLUBLE MOLYBDENUM SULFIDE FROM THE SOLUTION BY FILTRATION, ADDING FLUORINE IN THE FORM OF A SOLUBLE FLUORINE SALT OR HYDROFLUORIC ACID TO THE ACIDIFIED LIQUOR IN A QUANTITY TO GIVE AT LEAST 6 MOLES OF FLUORINE FOR EVERY MOLECULE OF SILICA AND PHOSPHORUS CONTAINED IN THE SOLUTION, CONTACTING THE ACIDIFIED AND FLUORINE TREATED ACIDIC SOLUTION WITH A KEROSENE SOLUTION CONTAINING A HYDROPHOBIC ORGANIC AMINE COMPOSITION CAPABLE OF FORMING A WATER INSOLUBLE ORGANIC AMINE TUNGSTEN COMPLEX AND EXTRACTING THE TUNGSTEN CONTENT OF THE AQUEOUS PHASE INTO THE ORGANIC PHASE, WASHING THE ORGANIC PHASE WITH WATER TO SEPARATE MECHANICALLY ENTRAINED AQUEOUS IMPURITIES, CONTACTING THE SEPARATED AND WASHED ORGANIC PHASE WITH A PURE AQUEOUS AMMONIA SOLUTION CONTAINING SUFFICIENT AMMONIA TO FORM AMMONIUM TUNGSTATE WITH THE TUNGSTEN CONTAINED IN THE ORGANIC AND, IN ADDITION, TO GIVE A PH OF AT LEAST 7.5 WHEREBY THE TUNGSTEN CONTENT OF THE ORGANIC IS EXTRACTED INTO THE AQUEOUS AMMONIUM HYDROXIDE SOLUTION, ADDING SOLID MAGNESIUM OXIDE TO THE AMMONIA EXTRACT SOLUTION TO PRECIPITATE CONTAINED PHOSPHORUS AS AMMONIUM MAGNESIUM PHOSPHATE, SEPARATING THE PHOSPHORUS COMPOSITION SO PRECIPITATED FROM THE SOLUTION, CLARIFYING THE AMMONIUM HYDROXIDE SOLUTION CONTAINING THE EXTRACTED TUNGSTEN BY FILTRATION, SUBJECTING THE CLARIFIED SOLUTION TO EVAPORATION TO EXPEL MOST OF THE WATER AND CONTAINED AMMONIA WHEREBY INSOLUBLE AMMONIUM PARATUNGSTATE IS FORMED, AND DISCHARGING DRIED INSOLUBLE AMMONIUM PARATUNGSTATE CRYSTALS AS A FINAL PRODUCT OF THE TREATMENT.