Abstract: A sulfate process for producing titania from a titaniferous material is disclosed. The process includes leaching the titaniferous material and producing a leach liquor, separating titanyl sulfate from leach liquor, hydrolysis of the extracted titanyl sulfate, and thereafter calcining the solid phase produced in the hydrolysis step. The process is characterised by controlling the hydrolysis step and forming a selected particle size distribution of hydrated titanium oxides from titanyl sulfate.

Abstract: A sulfate process for producing titania from a titaniferous material is disclosed. The process includes leaching the titaniferous material and producing a leach liquor, separating titanyl sulfate from leach liquor, hydrolysis of the extracted titanyl sulfate, and thereafter calcining the solid phase produced in the hydrolysis step. The process is characterised by multiple stage leaching of the titaniferous material.

Abstract: A sulfate process for producing titania from a titaniferous material is disclosed. The process includes leaching the titaniferous material and producing a leach liquor, precipitating iron sulfate from the leach liquor, solvent extraction of titanyl sulfate from leach liquor, hydrolysis of the extracted titanyl sulfate, and thereafter calcining the solid phase produced in the hydrolysis step. The process is characterised by using at least part of the raffinate from the solvent extraction step as at least part of the leach solution in the initial leach step.

Abstract: A process is provided for the recovery of a metallic nickel product in a solvent extraction process which includes the steps of forming a nickel ammine complex by stripping nickel from a nickel loaded organic phase with a high strength ammonia solution and then reducing the nickel ammine complex with hydrogen from the high strength ammonia solution to produce a metallic nickel product. By virtue of the present process, a reductive precipitation of nickel by hydrogen is obtained so as to recover a metallic nickel product, and the process is advantageous in that it will allow for commercial processes wherein nickel may be recovered by hydrogen reduction based on high strength ammonia solutions.

Abstract: A sulfate process for producing titania from titaniferous material is disclosed. The process includes precipitating titanyl sulfate from leach liquors containing acidic solutions of titanyl sulfate. The process is characterised by: (a) multiple stage leaching to produce leach liquors containing acidic solutions of titanyl sulfate; (b) using depleted leach liquor from a titanyl sulfate precipitation reactor in the leach steps; and (c) controlling acid concentration in the leach steps to avoid premature hydrolysis and premature precipitation.