Recovery of titanium values from ilmenite etc. - by leaching reduced ore with solution of controlled solution potential

摘要

Ti values are recovered by subjecting the ground ilmenite to a reductive roast, leaching with a soln. comprising halogen cpd., sepg. gangue, pptg. TiO2 by treatment with iron oxide and sepg. TiO2. Prior to leaching, the soln. potential is adjusted to +150 to -50mV measured against satd. calomel electrode by addn. of metallic Fe or reduced iron cpd. (when >150mV) or an oxidised soln. of Fe3+ as chloro complex (when -50mV). This potential is monitored and maintained during leaching. Ti losses are minimised.