| 摘要 |
1294703 Leaching titaniferous materials; titanium phosphate BRITISH TITAN Ltd 5 May 1971 [16 May 1970] 23851/70 Headings C1A and C1N An iron-containing titaniferous material is leached with aqueous HCl to form a TiO 2 concentrate and a solution containing dissolved Fe and some Ti; H 3 PO 4 or a phosphate is added to the separated solution to precipitate Ti phosphate; and HCl and Fe oxide or Fe are recovered from the solution. The initial material may be ilmenite or leucoxene having a particle size of 50-200 Á and may be subjected to a preliminary oxidation and reduction (e.g. in H 2 +2% steam). The leach may be effected at 80‹ C. to the b.pt. using 18-22% acid, while agitating with N 2 . A 2-stage leach may be used, as described in Specification 1,282,506. The PO 4 is preferably provided as H 3 PO 4 or NH 4 phosphate, using 30-200% of the stoichiometric amount required to remove Ti as Ti 3 (PO 4 ) 4 , and the solution may be heated before or after PO 4 addition. An oxidizing agent may also be added, e.g. air, H 2 O 2 , or excess FeCl 3 . |
