A process for recovering titanium dioxide from a titanium-bearing material, the process including the steps of: leaching the titanium-bearing material in a first leaching step at atmospheric pressure and at a temperature of 70 to 97° C. with a first lixiviant to produce a first leach solution comprising undissolved first leach solids that include a titanium content and a first leach liquor, the first lixiviant comprising hydrochloric acid at a concentration of less than 23% w/w; separating the first leach liquor and the undissolved first leach solids; leaching the first leach solids in a second leaching step at atmospheric pressure and at a temperature of 60 to 80° C. with a second lixiviant in the presence of a Fe powder reductant to produce a second leach solution comprising undissolved second each solids and a second leach liquor that includes a leached titanium content and iron content, the second lixiviant comprising a mixed chloride solution comprising less than 23% w/w hydrochloric acid and an additional chloride selected from alkali metal chlorides, magnesium chloride and calcium chloride, or mixtures thereof; separating the second leach liquor and the undissolved second leach solids; and thereafter separating the titanium dioxide and the iron content from the second leach liquor by precipitation, and regenerating the second lixiviant for recycle to the second leaching step.

A method for the preparation of titanium dioxide, the method comprising the steps of subjecting a titanium containing leach residue to a concentrated sulfuric acid digest step; and in turn subjecting that residue to a leach in dilute sulfuric acid, whereby a black liquor is obtained and from which titanium dioxide is in turn obtained.

A method for recovering metal oxides from a paint sludge. The method may include obtaining a first mixture by evaporating an organic part of the paint sludge. Evaporating the organic part of the paint sludge may include heating the paint sludge in a furnace. The method may further include precipitating a second mixture from the first mixture by mixing the first mixture and a sodium hydroxide solution. The method may further include recovering titanium dioxide from the second mixture by mixing the second mixture with a hydrochloric acid solution.

The present invention relates to metallurgical processes, and more particularly to a process for producing titaniferous feedstock and fines, a process for agglomerating titaniferous fines, and a process for producing titaniferous metals and titaniferous alloys. Recovery of rare-earth, vanadium and scandium from titanium iron bearing resources is also disclosed. Selective leaching for Scandium recovery from all magnetite type resources such as ilmenite, ferro titanic resources, nickel laterites, magnetite iron resources etc.

The present invention relates to the processing of natural titanium-containing feedstock, mainly ilmenite concentrate, including ilmenite ores with a low TiO.sub.2 content, into products with high added value without generating any liquid or solid waste. The method according to the invention comprises the following stages: digesting ilmenite concentrate, processing the solid residue following ilmenite concentrate digestion, hydrolysis of titanium oxychloride, washing titanium oxides/hydroxides precipitate from impurities, calcination of titanium oxides/hydroxides precipitate, precipitation of iron hydroxides to obtain black, red and yellow iron oxide pigments, processing the mother liquor containing calcium chloride, regeneration of hydrogen chloride from ammonium chloride solution, obtaining ammonium sulfate and ammonium sulfate crystallization, obtaining crystalline ammonium chloride. The resulting products are pigments, pigment fillers, mineral fertilizers, construction materials, raw materials for the production of metals, and other products; they are used in various fields of application such as paint and coatings industry, pulp and paper industry, in the production of plastics, in metallurgy, in agricultural, construction industries and others.

Provided is a method for preparing a reduced titanium powder by a multistage deep reduction, including the following steps of: uniformly mixing a dried titanium dioxide powder with a magnesium powder to obtain a mixture, adding the mixture in a self-propagating reaction furnace, triggering a self-propagating reaction, obtaining an intermediate product of which low-valence titanium oxides Ti.sub.xO are dispersed in an MgO matrix, leaching the intermediate product with a hydrochloric acid as a leaching solution, performing filtering, washing and vacuum drying to obtain a low-valence titanium oxide Ti.sub.xO precursor, uniformly mixing the low-valence titanium oxide Ti.sub.xO precursor with a calcium powder, performing a pressing to obtain semi-finished products, placing the semi-finished products in a vacuum reduction furnace for a second-time deep reduction, and leaching a deep reduction product with a hydrochloric acid as a leaching solution so as to obtain the reduced titanium powder.

The present invention relates to the recovery of rare earths, scandium, niobium, tantalum, zirconium, hafnium, titanium, and the like from ores or concentrates containing fluorine. More specifically, the ores or concentrates are pretreated by carbochlorination to convert the rare earths and other metals into their chlorides and then subjected to dilute hydrochloric acid leaching to recover the valuable rare earths and other metals from the leachate. Niobium, tantalum, zirconium, hafnium, and titanium can be recovered as their chlorides or oxychlorides from the gaseous products of carbochlorination, or converted into their oxides while simultaneously regenerating chlorine.

A process operating at super-atmospheric pressure for leaching a titanium containing ore with an HCl and producing titanium dioxide with integrated steps of solvent extraction for removing iron from the leached ore and solvent extraction of a resulting titanium enriched raffinate to produce particles suitable for finishing into pigment grade TiO.sub.2. The process can integrate the recovery of HCl from both solvent recovery steps and the recovery of solvent. The process also produces commercial grade ferric chloride.

Provided is a method for preparing a reduced titanium powder by a multistage deep reduction, including the following steps of: uniformly mixing a dried titanium dioxide powder with a magnesium powder to obtain a mixture, adding the mixture in a self-propagating reaction furnace, triggering a self-propagating reaction, obtaining an intermediate product of which low-valence titanium oxides Ti.sub.xO are dispersed in an MgO matrix, leaching the intermediate product with a hydrochloric acid as a leaching solution, performing filtering, washing and vacuum drying to obtain a low-valence titanium oxide Ti.sub.xO precursor, uniformly mixing the low-valence titanium oxide Ti.sub.xO precursor with a calcium powder, performing a pressing to obtain semi-finished products, placing the semi-finished products in a vacuum reduction furnace for a second-time deep reduction, and leaching a deep reduction product with a hydrochloric acid as a leaching solution so as to obtain the reduced titanium powder.

A process for leaching a value metal from a titaniferous ore material comprising the step of leaching the ore material at atmospheric pressure with a lixiviant comprising magnesium chloride and hydrochloric acid is disclosed. Iron and titanium are leached into solution. Iron in the ferric state may be separated from titanium in solution using extraction with alkyl ketone. More effective separation of titanium with lower contamination with iron is obtained.