Titanium dioxide manufacture

FIGURE 1 Titanium dioxide manufacture by die sulfate process. 

FIGURE 2 Titanium dioxide manufacture by the chloride process. 

Titanium Dioxide Manufacturer Distributor llmenite Mining Iron-Based Chemicals... 

Metal ion impurities in spent acid impose different recovery problems. For instance, iron residues in the spent acid from titanium dioxide manufacture may be removed by crystallization of first FeS04 7FI2O followed by crops of various iron(II) salts, or by electrodialysis [67]. Incidentally electrodialysis has also been used for sulfuric acid recovery from wastewater, either directly or after preconcentration on cation exchange resin [68]. 

Rutile grades of titanium dioxide are used exclusively. Some are treated to enhance both pigment wetting characteristics and exterior durability properties. Foimulators should follow the titanium dioxide manufacturers recommendations for the selection of suitable grades. 

The iron (II) sulfate is often obtained as a by-product from steel pickling or titanium dioxide manufacture. 

Titanium Tetrachloride. The major use for titanium tetrachloride [7550 5-0] is in titanium dioxide production, and titanium dioxide [13463-67-7] is enjoying strong growth for use as a filler in pulp and paper manufacture and as a pigment in paint and plastic manufacture. Annual growth for this product is forecasted at between 2.5 and 3.0% through 1992. 

Annual world production of titanium carbide is thousands of metric tons. It is manufactured mainly in-house by cutting-tool manufacturers by the reduction of titanium dioxide with carbon ... 

Precipitation of a hydrated titanium oxide by mixing aqueous solutions of titanium chloride with alkaU forms the precipitation seeds, which are used to initiate precipitation in the Mecklenburg (50) variant of the sulfate process for the production of pigmentary titanium dioxide. Hydrolysis of aqueous solutions of titanium chloride is also used for the preparation of high purity (>99.999%) titanium dioxide for electroceramic appHcations (see Ceramics). In addition, hydrated titanium dioxide is used as a pure starting material for the manufacture of other titanium compounds. 

The main electroceramic apphcations of titanium dioxide derive from its high dielectric constant (see Table 6). Rutile itself can be used as a dielectric iu multilayer capacitors, but it is much more common to use Ti02 for the manufacture of alkaline-earth titanates, eg, by the cocalciuation of barium carbonate and anatase. The electrical properties of these dielectrics are extremely sensitive to the presence of small (<20 ppm) quantities of impurities, and high performance titanates require consistently pure (eg, >99.9%) Ti02- Typical products are made by the hydrolysis of high purity titanium tetrachloride. 

Fig. 1. Flow diagram for the manufacture of titanium dioxide pigments.

Alkaline-Earth Titanates. Some physical properties of representative alkaline-earth titanates ate Hsted in Table 15. The most important apphcations of these titanates are in the manufacture of electronic components (109). The most important member of the class is barium titanate, BaTi03, which owes its significance to its exceptionally high dielectric constant and its piezoelectric and ferroelectric properties. Further, because barium titanate easily forms solid solutions with strontium titanate, lead titanate, zirconium oxide, and tin oxide, the electrical properties can be modified within wide limits. Barium titanate may be made by, eg, cocalcination of barium carbonate and titanium dioxide at ca 1200°C. With the exception of Ba2Ti04, barium orthotitanate, titanates do not contain discrete TiO ions but ate mixed oxides. Ba2Ti04 has the P-K SO stmcture in which distorted tetrahedral TiO ions occur. 

Iron Titanates. Ferrous metatitanate [12168-52-4] FeTiO, mp ca 1470°C, density 472(0), an opaque black soHd having a metallic luster, occurs in nature as the mineral ilmenite. This ore is used extensively as a feedstock for the manufacture of titanium dioxide pigments. Artificial ilmenite may be made by heating a mixture of ferrous oxide and titanium oxide for several hours at 1200°C or by reducing a titanium dioxide/ferric oxide mixture at 450°C. 

Spherical, Fine-Particle Titanium Dioxide. Spherical, fine-particle titanium dioxide that has no agglomeration and of mono-dispersion can be manufactured by carrying out a gas-phase reaction between a tetraalkyl titanate vapor and methanol vapor in a carrier gas to form an initial fine particle, which can then be hydrolyzed with water or steam (572). 

Titanium Dioxide Hollow Fibers. HoUow fibers of titanium dioxide can be manufactured by preparing a solution of a tetraalkyl titanate, an acid such as HCl, and an alcohol such as isopropyl alcohol, followed by spinning and drying the resultant fiber (573). 

W. Kampfer, and E. Stieg, Jr., Color Eng. 44, 35—40, 44 (1967). A description of the manufacture, properties, and uses of titanium dioxide as a colorant for paint, food, plastics, and other materials. 

Sawdust may be employed in cases where the suspension particles consist of a valuable product that may be roasted. For example, titanium dioxide is manufactured by calcining a mixture of sawdust and metal titanium acid. The mixture is obtained as a filter cake after separating the corresponding suspension with a layer of filter aid. 

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