Titanium Dioxide (Anatase)

General Properties

Titanium dioxide is a chemical that can be found as  mine in nature. It is found in different crystalline forms. It is found in three different types; rutile, anatase and brookite. However, only anatase and rutile forms are preferred.

 It is black when it is extracted from mine. It is white in pure form. Titanium is oxidized metal and its refracture index is high. Therefore, it is used as pigment in dye production.

Titanium dioxide anatase’s refracture index is lower than rutile and it is also softer. Therefore, titanium dioxide rutile is more successful as pigment but anatase is preferred in other fields. Anatase also has lower cost.

Anatase is also more suitable to nanotechnological applications and solar panels due to its crystalline nature.

Production

Titanium dioxide’s production method depends on raw material. Most common mineral source is ilmenite. Also, it can be naturally found as rutile.

Rutile is purified by chlorination. Ilmenite is removed from its irons by sulphate or chloride process and it transforms into titanium dioxide.

Both sulphate and chloride process create  titanium dioxide in rutile form. Anatase is acquired by sulphate process through certain adjustments.

Applications

Titanium dioxide is mostly used in dye production. It has one of the highest refracture index. This makes it ideal for dye production. It can be used as raw material in both  anatse and rutile forms. Rutile has higher refracture index but anatase has lower cost. Anatase is preferred in food coloring as it is softer. Titanium dioxide has two problems, however. One is its tendacy to flocculation. It must be dissolved in chemicals such as propylene glycol, glycerin.

Second is its crystalline structure. Its the crystalline structure that gives titanium dioxide its reactivity. It must be removed from impurity before it is used.

It is also preferred in toothpaste, juice, dessert and dairy products. It is also used in cosmetic products and sunscreens. It provides good protection from UV beams.

It has very special fields of usage due to its photocatalytic properties. Therefore, it is used in hydrogen and anti-bacterial coating productions. Its photosensetive properties makes it ideal for solar panel production.

It is also used in nanotube production. Thanks to its nanotechnological advantages, researches conducted on titanium dioxide are increased.  

Safety Measures and Toxic Values

Researches revealed that titanium dioxide is carcinogenic for human health. It is estimated that this is connected to its particle size. In powder form, it damages to respiratory system and it is irritant for eyes. It may be dangerous if it is inhaled for long time.

Certain food producers have reduced its usage and France enacted that its usage will be prohibited. Nevertheless, its worldwide usage continues.