Titanium dioxide Chemical Properties
- Melting point:
- 1840 °C
- Boiling point:
- 2900 °C
- 4.26 g/mL at 25 °C(lit.)
- refractive index
- Flash point:
- storage temp.
- Practically insoluble in water. It does not dissolve in dilute mineral acids but dissolves slowly in hot concentrated sulfuric acid.
- White to slightly yellow
- Specific Gravity
- 7-8 (100g/l, H2O, 20℃)(slurry)
- Water Solubility
- CAS DataBase Reference
- 13463-67-7(CAS DataBase Reference)
- NIST Chemistry Reference
- Titanium dioxide(13463-67-7)
- EPA Substance Registry System
- Titanium dioxide (13463-67-7)
Titanium dioxide Usage And Synthesis
Titanium (IV) dioxide (TiO2), also known as rutile, is one of the best-known compounds used as a paint pigment. It is ideal for paints exposed to severe temperatures and marine climates because of its inertness and self-cleaning attributes. It is also used in manufacture of glassware, ceramics, enamels, welding rods, and floor coverings.
The naturally occurring dioxide exists in three crystal forms: anatase, rutile and brookite. While rutile, the most common form, has an octahedral structure. Anatase and brookite have very distorted octahedra of oxygen atoms surrounding each titanium atom. In such distorted octahedral structures, two oxygen atoms are relatively closer to titanium than the other four oxygen atoms. Anatase is more stable than the rutile form by about 8 to 12 kJ/mol (Cotton, F.A., Wilkinson, G., Murillo, C.A and M Bochmann. 1999. Advanced Inorganic Chemistry, 6th ed, p. 697, New York: John Wiley & Sons) Other physical properties are: density 4.23g/cm3; Mohs hardness 5.8 g/cm3 ( anatase and brookite) and 6.2 g/cm3 ( rutile); index of refraction 2.488 (anatase), 2.583 (brookite) and 2.609 (rutile); melts at 1,843°C; insoluble in water and dilute acids; soluble in concentrated acids.
Ttitanium dioxide is an odorless white powder.
White, amorphous, odorless, and tasteless nonhygroscopic powder.
Although the average particle size of titanium dioxide powder is less
than 1 mm, commercial titanium dioxide generally occurs as
aggregated particles of approximately 100 mm diameter.
Titanium dioxide may occur in several different crystalline forms: rutile; anatase; and brookite. Of these, rutile and anatase are the only forms of commercial importance. Rutile is the more thermodynamically stable crystalline form, but anatase is the form most commonly used in pharmaceutical applications.
Titanium dioxide is an extreme white and bright compound with high index of refraction. In paints it is a white pigment and an opacifying agent.It is in house paints, water paints, lacquers, enamels, paper filling and coating, rubber, plastics, printing ink, synthetic fabrics, floor coverings, and shoe whiteners. Also, it is used in colorants for ceramics and coatings for welding rods. A rutile form of the dioxide is used in synthetic gem stones.
Airfloated ilmenite is used for titanium pigment manufacture. Rutile sand is suitable for welding-rod-coating materials, as ceramic colorant, as source of titanium metal. As color in the food industry. Anatase titanium dioxide is used for welding-rod-coatings, acid resistant vitreous enamels, in specification paints, exterior white house paints, acetate rayon, white interior air-dry and baked enamels and lacquers, inks and plastics, for paper filling and coating, in water paints, tanners' leather finishes, shoe whiteners, and ceramics. High opacity and tinting values are claimed for rutile-like pigments.
titanium dioxide (TiO2) is one of the 21 FDA-approved sunscreen chemicals with an approved usage level of 2 to 25 percent. When applied, titanium dioxide remains on the skin’s surface, scattering uV light. It is often used in conjunction with other sunscreen chemicals to boost the product’s SPF value, thus reducing the risk of irritation or allergies attributed to excessive usage of chemical sunscreens. Its incorporation into sunscreen formulations, makeup bases, and daytime moisturizers depends on the particular size of titanium dioxide employed. The smaller the particle size, the more unobtrusive Tio2’s application. Large particles, on the other hand, leave a whitish wash or look on the skin. Some companies list “micro” or “ultra” when referring to the size of the titanium dioxide particle. According to some sources, titanium dioxide could be the ideal uVA/uVB protection component given its chemical, cosmetic, and physical characteristics. Titanium dioxide is also used to provide a white color to cosmetic preparations.
Titanium Dioxide is a white pigment that disperses in liquids and possesses great opacifying power. the crystalline modifications of titanium dioxide are rutile and anatase, of which only anatase finds use as a color additive.
Titanium dioxide is mined from natural deposits. It also is produced from other titanium minerals or prepared in the laboratory. Pigment-grade dioxide is produced from the minerals, rutile and ilmenite. Rutile is converted to pigment grade rutile by chlorination to give titanium tetrachloride, TiCl4. Anhydrous tetrachloride is converted back to purified rutile form by vapor phase oxidation.
Anatase form is obtained by hydrolytic precipitation of titanium(IV) sulfate on heating. The mineral ilmenite is treated with concentrated sulfuric acid. Heating the sulfate solution precipitates hydrous titanium oxide. The precipitate is calcined to expel all water.
Titanium dioxide also can be prepared by heating Ti metal in air or oxygen at elevated temperatures.
Titanium dioxide occurs naturally as the minerals rutile (tetragonal
structure), anatase (tetragonal structure), and brookite (orthorhombic
Titanium dioxide may be prepared commercially by either the sulfate or chloride process. In the sulfate process a titanium containing ore, such as ilemenite, is digested in sulfuric acid. This step is followed by dissolving the sulfates in water, then precipitating the hydrous titanium dioxide using hydrolysis. Finally, the product is calcinated at high temperature. In the chloride process, the dry ore is chlorinated at high temperature to form titanium tetrachloride, which is subsequently oxidized to form titanium dioxide.
There are two major processes for the manufacture of titanium dioxide
pigments, namely sulfate route and chloride route. In the sulfate
process, the ore limonite, FeOTiO2, is dissolved in sulfuric acid and
the resultant solution is hydrolyzed by boiling to produce a hydrated
oxide, while the iron remains in solution. The precipitated titanium
hydrate is washed and leached free of soluble impurities. Controlled calcinations
at about 1000°C produce pigmentary titanium dioxide of the
correct crystal size distribution; this material is then subjected to a finishing
coating treatment and milling.
The chloride process uses gaseous chlorination of mineral rutile, followed by distillation and finally a vapor phase oxidation of the titanium tetrachloride.
Lower respiratory tract irritant. Possible carcinogen.
Titanium dioxide is widely used in confectionery, cosmetics, and
foods, in the plastics industry, and in topical and oral pharmaceutical
formulations as a white pigment.
Owing to its high refractive index, titanium dioxide has lightscattering properties that may be exploited in its use as a white pigment and opacifier. The range of light that is scattered can be altered by varying the particle size of the titanium dioxide powder. For example, titanium dioxide with an average particle size of 230nm scatters visible light, while titanium dioxide with an average particle size of 60nm scatters ultraviolet light and reflects visible light.
In pharmaceutical formulations, titanium dioxide is used as a white pigment in film-coating suspensions, sugar-coated tablets, and gelatin capsules. Titanium dioxide may also be admixed with other pigments.
Titanium dioxide is also used in dermatological preparations and cosmetics, such as sunscreens.
A nuisance dust. A human skin irritant. Questionable carcinogen with experimental carcinogenic, neoplastigenic, and tumorigenic data. Violent or incandescent reaction with metals at high temperatures (e.g., aluminum, calcium, magnesium, potassium, sodium, zinc, lithium). See also TITANIUM COMPOUNDS.
Titanium dioxide is widely used in foods and oral and topical pharmaceutical formulations. It is generally regarded as an essentially nonirritant and nontoxic excipient.
Titanium dioxide is a white pigment used as a pigment in paint; in the rubber, plastics, ceramics, paint, and varnish industries, in dermatological preparations; and is used as a starting material for other titanium compounds; as a gem; in curing concrete; and in coatings for welding rods. It is also used in paper and cardboard manufacture.
Carcinogenesis. In a 1985 study, rats (CD) were exposed to graded airborne concentrations (0, 10, 50, and 250mg/m3) of TiO2 6 h/day, 5 days/week, for 2 years. The majority of the particles were in the respirable range (84% ≤13 mmMMD). All responses were confined to the lungs. At the lowest dose, the histopathological evaluation of the lungs revealed dust-laden macrophages in the alveolar ducts and adjacent alveoli with pneumocyte hyperplasia. At the two highest concentrations, there were increases in lung weight, accumulation of dust in the macrophages, foamy macrophage responses, type II pneumocyte hyperplasia, alveolar proteinosis, alveolar bronchiolization, cholesterol granulomas, focal pleurisy, and dust deposition in the tracheobronchiolar lymph nodes. At the 250mg/m3 exposure concentration, bronchiole alveolar adenomas (males: control 2/79, 250mg/m3 12/79; females: control 0/79, 250mg/m3 13/79) increased. Additionally, 13/79 females at the 250mg/m3 dose showed squamous cell carcinoma, compared with none in 79 controls. Theauthorsnoted that this responsemight have little biological relevance to humans because of the overload of respiratory clearance mechanisms and also pointed out that the type, location, and development of the tumors were different from those in human lung tumors. It is not clear that the nasal cavity epithelium was examined. However, the nasal cavity load would be expected to be higher in the rats because of anatomic structure, whereas the lung deposition should be higher in humans because we are, in part, mouth breathers.
Titanium dioxide is extremely stable at high temperatures. This is
due to the strong bond between the tetravalent titanium ion and the
bivalent oxygen ions. However, titanium dioxide can lose small,
unweighable amounts of oxygen by interaction with radiant energy.
This oxygen can easily recombine again as a part of a reversible
photochemical reaction, particularly if there is no oxidizable
material available. These small oxygen losses are important because
they can cause significant changes in the optical and electrical
properties of the pigment.
Titanium dioxide should be stored in a well-closed container, protected from light, in a cool, dry place.
Titanium dioxide is incompatible with strong oxidizers and strong acids. Violent or incandescent reactions may occur with metals (e.g., aluminum, calcium, magnesium, potassium, sodium, zinc, and lithium).
Owing to a photocatalytic effect, titanium dioxide may interact
with certain active substances, e.g. famotidine. Studies have shown that titanium dioxide monatonically degrades film mechanical
properties and increases water vapor permeability of polyvinyl
alcohol coatings when used as an inert filler and whitener.
Titanium dioxide has also been shown to induce photooxidation of unsaturated lipids.
Accepted as a food additive in Europe. Included in the FDA Inactive Ingredients Database (dental paste; intrauterine suppositories; ophthalmic preparations; oral capsules, suspensions, tablets; topical and transdermal preparations). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.
Titanium dioxide Preparation Products And Raw materials
- Sebacic acid
- Epoxidized soya bean oil
- Titanium dioxide for porcelain enamel
- Physical sun screener
- Titanium dioxide for ceramics
- 5-ALPHA, 20-ALPHA, 22-ALPHA, 25D-SPIROSTAN-3-BETA, 11-ALPHA-DIOL
- TITANIUM DIOXIDE RUTILE/ANATUS
- Mica Titanium Dioxide Pearlescent Pigment
- Titanium Dioxide for picture tube
- 5,20-ALPHA, 22-ALPHA, 25D-SPIROSTEN-3-BETA-OL ACETATE
- Titanium dioxide
- Thiourea dioxide
- sulfur dioxide
- Chlorine dioxide
- Titanium dioxide,nanometre
- 010-82848833- ;010-82848833-