Titanium dioxide NEW

Chinese name: Titanium dioxide

Titanium(IV) oxide

CAS: 13463-67-7

EINECS: 257-372-4

Chemical formula: O2Ti

Molecular weight: 79.8658

InChI: InChI=1/2O.Ti/rO2Ti/c1-3-2

InChIKey: SOQBVABWOPYFQZ-UHFFFAOYSA-N

Density: 4.17 g/mL at 25 °C(lit.)

Melting point :1830-3000℃

Boiling point :2900℃

insoluble: insoluble

PH value: < 1

Storage condition: Room Temprature

Appearance: powder, color White

Physical and chemical properties: white powder.

Soft texture of odorless tasteless white powder, covering power and coloring power, melting point 1560 ~ 1580℃. Insoluble in water, dilute inorganic acid, organic solvent, oil, slightly soluble in alkali, soluble in concentrated sulfuric acid. It turns yellow when heated and turns white when cooled. Rutile type (R type) has a density of 4.26g/cm3 and a refractive index of 2.72. R-type titanium dioxide has the characteristics of good weather resistance, water resistance and not easy to yellowing, but the whiteness is slightly poor. Anatase (Type A) has a density of 3.84g/cm3 and a refractive index of 2.55. Type A titanium dioxide has poor light resistance and is not resistant to weathering, but the whiteness is better. In recent years, it has been found that nano-scale ultra-fine titanium dioxide (usually 10 ~ 50 nm) has semiconductor properties, and has high stability, high transparency, high activity and high dispersion, no toxicity and color effect.

Application: Used in paint, ink, plastic, rubber, paper, chemical fiber and other industries; Titanium dioxide (nanoscale) is widely used in functional ceramics, catalysts, cosmetics and photosensitive materials

White inorganic pigment. It is one of the strongest colors in white pigments, with excellent hiding power and coloring fastness, suitable for opaque white products. Rutile type is especially suitable for outdoor use of plastic products, can give products good light stability. Anatase type is mainly used for indoor use products, but slightly blue light, high whiteness, large hiding power, strong coloring power and good dispersion. Titanium dioxide is widely used as paint, paper, rubber, plastic, enamel, glass, cosmetics, ink, watercolor and oil color pigments, can also be used in metallurgy, radio, ceramics, welding rods

nature

White amorphous powder. Naturally occurring titanium dioxide comes in three variants: rutile is a tetragonal crystal; Anatase is tetragonal crystal; Titanite is an orthogonal crystal. Mild heat is yellow, strong heat is brown. Insoluble in water, hydrochloric acid or nitric acid or dilute sulfuric acid and organic solvents, soluble in concentrated sulfuric acid, hydrofluoric acid, slightly soluble in alkali and hot nitric acid. Long boiling time can dissolve in concentrated sulfuric acid and hydrofluoric acid. It reacts with molten sodium hydroxide to form titanate. At high temperatures, it can be reduced to low-priced titanium compounds by hydrogen, carbon, sodium metal, etc., and react with carbon disulfide to produce titanium disulfide. The refractive index of titanium dioxide is the largest among white pigments, with rutile type being 8.70 and anatase type 2.55. Since both anatase and plate titanium dioxide convert to rutile at high temperatures, the melting and boiling points of plate titanium and anatase titanium dioxide are virtually non-existent. Only rutile titanium dioxide has a melting point and boiling point, and the melting point of rutile titanium dioxide is 1850 ° C, the melting point in the air (1830 soil 15) ° C, and the melting point in the oxygen rich 1879 ° C, and the melting point is related to the purity of titanium dioxide. The boiling point of rutile type titanium dioxide is (3200 soil 300)K, and titanium dioxide is slightly volatile at this high temperature.

preparation

Industrial titanium oxide sulfate is dissolved in water and filtered. Add ammonia water to precipitate gruel, and then filter. Then it is dissolved with oxalic acid solution, and then precipitated and filtered with ammonia water. The obtained precipitate is dried at 170℃ and then roasted at 540℃ to obtain pure titanium dioxide.

It's mostly open-pit mining. The beneficiation of titanium primary ore can be divided into three stages: preseparation (common magnetic separation and gravity separation), iron separation (magnetic separation), titanium separation (gravity separation, magnetic separation, electric separation and flotation). The beneficiation of titanium-zirconium placer (mainly seaside placer, followed by inland placer) can be divided into two stages of roughing and selecting. In 1995, the Zhengzhou Comprehensive Utilization Research Institute of the Ministry of Geology and Mineral Resources used magnetic separation, gravity separation and acid leaching processes to beneficiate the extra-large rutile mine in Xixia, Henan Province, which has passed trial production and all indicators are at the leading level in China.