Titanium Dioxide TiO2

Titanium Dioxide Identification

• Synonyms: Titanium (IV) Oxide; C.I. 77891; Titania
• CAS No.: 13463-67-7
• Molecular Weight: 79.87
• Chemical Formula: TiO2

Titanium dioxide, also known as titanium oxide or titania, is the naturally occurring oxide of titanium, chemical formula TiO2.

Titanium Dioxide - strongest, most brilliant white available to artists in the entire history of art. Its chemical stability is likewise outstanding.

Titanium dioxide occurs in three forms:

• anatase or octahedrite, a tetragonal mineral of octahedral habit; and
  brookite, an orthorhombic mineral. Both octahedrite and brookite are relatively rare minerals.
• rutile, a tetragonal mineral usually of prismatic habit, often twinned;
  

Pure titanium dioxide does not occur in nature but is derived from ilmenite or leuxocene ores. It is also readily mined in one of the purest forms, rutile beach sand.

Titanium dioxide is the most widely used white pigment because of its brightness and very high refractive index (n=2.4), in which it is surpassed only by diamond. When deposited as a thin film, its refractive index and color make it an excellent reflective optical coating for dielectric mirrors. TiO2 is also an effective opacifier in powder form, where it is employed as a pigment to provide whiteness and opacity to products such as paints, coatings, plastics, papers, inks, foods, and most toothpastes. In cosmetic and skin care products, titanium dioxide is used both as a pigment and a thickener, and in almost every sunblock with a physical blocker, titanium dioxide is found both because of its refractive index and its resistance to discoloration under ultraviolet light. This advantage enhances its stability and ability to protect the skin from ultraviolet light. It is also used in resistance-type lambda probes (a type of oxygen sensor).

Physical and Chemical Properties of TiO2

• Appearance: White Powder.
• Odor: Odorless.
• Solubility: Insoluble in water.
• Specific Gravity: 4.26
• pH: ca. 6 - 7 %
• Volatiles by volume @ 21C (70F): 0
• Boiling Point: 2500 - 3000C (4532 - 5432F)
• Melting Point: 1855C (3371F)
• Vapor Density (Air=1): Not applicable.
• Vapor Pressure (mm Hg): Not applicable.
• Evaporation Rate (BuAc=1): No information found.

Titanium Dioxide, particularly in the anatase form, is a photocatalyst under ultraviolet light. The strong oxidative potential of the positive holes oxidizes water to create hydroxyl radicals. It can also oxidize oxygen or organic materials directly. Titanium dioxide is thus added to paints, cements, windows, tiles, or other products for sterilizing, deodorizing and anti-fouling properties. As TiO2 is exposed to UV light, it becomes increasingly hydrophilic, thus it can be used for anti-fogging coatings or self-cleaning windows. TiO2 incorporated into outdoor building materials can substantially reduce concentrations of airborne pollutants such as volatile organic compounds and NOx.

Emergency Overview: CAUTION! MAY CAUSE IRRITATION TO SKIN, EYES, AND RESPIRATORY TRACT. MAY AFFECT LUNGS.