Recovery of titanium metal values

Claim 1

In a process for the recovery of titanium metal values from a titanium bearing source which comprises the steps of: (a) grinding said titanium bearing source; (b) subjecting the ground titanium bearing source to a reductive roast in the presence of a reducing agent at an elevated temperature; (c) leaching the reduced source with a leach solution comprising a halogen containing compound; (d) separating the insoluble gangue from the soluble metal halides; (e) precipitating titanium dioxide from the soluble metal halides by treating with iron oxides; (f) separating said titanium dioxide from soluble iron halide; and (g) recovering the desired titanium dioxide, the improvement which comprises prior to effecting the leach of the reduced titanium bearing source adjusting the solution potential in the range of from about +150 millivolts to about -50 millivolts measured against a saturated calomel electrode by adding metallic iron or a reduced iron compound when the solution potential is in excess of +150 millivolts or an oxidized solution containing iron in the +3 valence state as a chlorocomplex when the solution potential is less than -50 millivolts, monitoring and maintaining the solution potential within said range during the leach to prevent formation of titanium dioxide.