Process for the decomposition of titanium dioxide-containing minerals with hydrochloric acid

Claim 1

A PROCESS FOR THE RECOVERY OF TITANIUM FROM TITANIFEROUS ORES WHICH COMPRISES: (A) LEACHING SAID ORES WITH CONCENTRATED HYDROCHLORIC ACID AT A TEMPERATURE OF BETWEEN 55* AND 65*C. THEREBY PRODUCING A SLURRY COMPRISING SOLID MATERIAL AND LIQUOR, SAID LIQUOR CONTAINING DISSOLVED THEREIN SUBSTANTIALLY ALL THE TITANIUM CONTENT OF SAID ORE, THE AMOUNT OF ACID USED BEING SUCH THAT THE LIQUOR CONTAINS 2 TO 5 MOLES OF HYDROGEN CHLORIDE PER MOLE OF DISSOLVED TITANIUM, (B) SEPARATING THE SOLID MATERIAL OF THE SLURRY FROM THE LIQUOR, (C) REDUCING DISSOLVED TRIVALENT IRON CHLORIDE CONTAINED IN THE LIQUOR TO DIVALENT IRON CHLORIDE, (D) SATURATING THE LIQUOR WITH HYDROGEN CHLORIDE AND SEPARATING THE RESULTING PRECIPITATE FROM THE LIQUOR, (E) EVAPORATING THE HYDROGEN CHLORIDE FROM THE LIQUOR, (F) DILUTING THE LIQUOR WITH WATER WHEREBY TITANIUM DIOXIDE HYDRATE IS PRECIPITATED AND (G) SEPARATING THE TITANIUM DIOXIDE HYDRATE FROM THE LIQUOR.