Patent ID: 8137647

Claim:
A process comprising: a) digesting ilmenite ore with aqueous ammonium hydrogen oxalate to form a leachate and a precipitate comprising FeC 2 O 4 .2H 2 O; b) separating said leachate from said precipitate comprising FeC 2 O 4 .2H 2 O; c) hydrolyzing said leachate with ammonia or ammonium hydroxide to form titanyl hydroxide and an oxalate-rich solution; d) separating said titanyl hydroxide from said oxalate-rich solution; e) washing said titanyl hydroxide with a material selected from the group consisting of water, aqueous ammonium oxalate and ammonium hydroxide to form low oxalate titanyl hydroxide, that is, titanyl hydroxide that is stripped of residual oxalate; and f) crystallizing titanium dioxide from said low oxalate titanyl hydroxide.