Titanium Dioxide

Titanium dioxide is an inorganic white compound, which has been used in many different products for about 100 years. Due to its non-toxic and non-reactive properties as well as high brightness, it has many applications. It is one of the whitest and brightest pigments known for its high reflectivity. It can also scatter ultraviolet rays. For this reason, buying and selling Titan is common in various industries. Titanium dioxide (TiO2) is a light white substance that is primarily used as a dye in a wide range of common products.

TiO2

 valued for its stunning white color, light scattering ability, and UV resistance, is a popular substance that is seen and used in hundreds of products every day and has significant benefits for our economy and quality of life. Across the EU, sales of titanium and TiO2 applications include paints, plastics, paper, medicines, sunscreens and foodstuffs. As a photocatalyst, titanium dioxide can be added to paints, cements, windows and tiles to decompose environmental pollutants. Also as a white pigment, TiO2 is one of the most important raw materials for paints and coatings.
Titanium dioxide or titania with the formula TiO2 has a specific gravity of 3.4-2.9, a melting point of 1854 ° C and a hardness of 5.6-5.5. Titanium dioxide is not soluble in water and organic acids and dilute alkaline solutions but is soluble in hot sulfuric acid and HF. Titanium dioxide is found in mineral ores (FeTiO3), perovskite (CaTiO3) and ilminurotyl titanium ores in mineral sources. Also, pure titanium dioxide is not widely used in industry, so it is mostly composed of TiO2 cores with multiple coatings of inorganic or organic materials. These additives increase the dispersion quality of titanium and make it better compatible with other polymer compounds.

The number and nature of layers,

as well as the particle size distribution, are the factors that distinguish different grades from each other. Titanium dioxide is found in nature in three different forms: rutile, anatase and brookite. Rutile is the most abundant and stable mineral, containing 98% TiO2, and is used in the manufacture of dielectrics and oxygen sensors at high temperatures. Anatase and brookite are converted to rutile by heat.
Anatase is a semiconductor material that due to its low cost and strong oxidation power against UV rays and its hydrophilic nature, it is mainly used in optical coatings, light-sensitive paints and light catalysts. Spatially, the rutile and anatase phases are tetragonal, and the brookite is orthorhombic.

Titanium dioxide production process

The method of producing titanium dioxide depends on the raw materials available. The most common source of titanium dioxide is the mineral ilmenite with the formula FeTiO3. After the ore of this material is extracted, it must be converted to its pure form through two processes and methods, “sulfate” and “chloride”.

Sulfate process

In this process, laminate (FeTiO3) is a common source for the production of the product, which reacts with concentrated sulfuric acid to extract titanium oxygen sulfate (TiOSO4) and eventually converts it to TiO2. In the sulfate method, a raw material called ilment is used. After crushing the stone, the impurities are separated with it. After grinding, it is dried and then dissolved in oleum. The oleum is slowly diluted with sulfuric acid and water. In this process, a solution of titanium sulfate, ferric sulfate together with silica is obtained.
By filtration, the insoluble silica is separated and some iron is added to the solution to convert all available iron into divalent salts. The solution is then separated and transferred to an evaporation tank after refining, and the ferrous sulfate is separated as a crystal. The next step is to boil the solution to hydrolyze titanium sulfate to titanium hydroxide. In this way, anatase-type titanium is prepared. The rutile type is prepared by adding rutile particles or adding zinc salt before hydrolysis.

Chloride process

This process requires the purest ore or rutile, which is very rare. Raw materials must contain at least 70% rutile. Titanium is first oxidized by reacting with carbon and then repeated with chlorine. The resulting TiCl4 liquid is distilled by contact with a pure oxygen flame or plasma at a temperature of 1200 to 1700 ° C and converted to TiO2.
In the chloride method, chlorinated gas is passed over a mixture of rutile rock at a temperature of 900 ° C. (The purity of titanium oxide in rutile ore is 95-96%). Titanium tetrachloride is liquefied by cooling and purified by distillation. Titanium tetrachloride burns at 1000 ° C in the presence of oxygen, which oxidizes to give titanium dioxide.
By precisely controlling the oxidation process, a purer titanium dioxide is obtained, which is completely white in color and has almost the same particle size.

Distribution and dispersion of titanium

Titanium and its application performs well when well dispersed throughout the product. In order to have the desired color, suitable resistance to changes in weather conditions, lack of transparency against UV rays and sunlight, the particle size must be less than 5 micrometers. In summary, the particle size distribution of titanium affects the following appearance characteristics: surface texture, spots on the surface, streaks on the product, lack of light transparency.

Types of pigments produced from titanium

According to ASTM standard, this material is produced as a pigment in 4 different types:

  • Type 1: It has at least 94% TiO2 and anatase grade type and this grade has the highest resistance.
  • Type 2: It has at least 92% TiO2 and type of rutile grade and this grade has medium resistance.
  • Type 3: It has 90% TiO2 and the type of grade is rutile and this grade has medium resistance.
  • Type 4: It has 80% TiO2 and type of rutile grade and this grade has high resistance.

Application of titanium dioxide

Pigment

The use of this substance as a pigment in the form of anatase was first reported in 1923 in France. Today, titanium dioxide is the most important white dye or pigment. When white pigment is needed, titanium dioxide is used. Rutile in decorative paints and glossy paints, the type of anatase in industrial paints where whiteness is an important issue. But its resistance to the weather is not so important.
Titanium dioxide is used in sunscreens and reflects the sun’s harmful rays. Generally used in the production of paint, paper, plastic, cement plus, UPVC. In addition to coloring the particles, it also creates a protective effect against UV.

Solar Cells

In solar cells, this material can be used as a substrate for DSSC cells due to its small particles and the reflection of sunlight.

make up products

Due to the small size of nanoparticles of this product and the lack of absorption of ultraviolet light and reflection of visible sunlight, and as a result, to help prevent skin cancer, this material has many applications in these products. This substance is used in a variety of personal products such as sunscreens, powder creams, whitening creams and… as a whitening agent or for filtering sunlight.

Catalysts

Due to the small particle size and high surface area of ​​this material, TiO2 as a nanomaterial allows the production of various catalysts with high surface activity. Recently, much research has been done on TiO2 due to its high level and stabilization of catalysts in the mesoporous structure as an alternative to heterogeneous catalysts. Due to low quantum efficiency and low adsorption capacity, high costs and problems in separation, the use of this material in large industries as a catalyst and a suitable alternative to heterogeneous catalysts has been limited, and research on this material as a catalyst support material (e.g. As a substrate) continues.

Other domains

The most important areas of application of titanium dioxide are paint, varnish (glaze), paper and plastic, which account for about 80% of the world’s titanium dioxide consumption. Other uses for pigments such as textiles, fibers, rubber, cosmetics and food are 8%. Others are used in other applications, such as the production of pure titanium, glass-ceramics, electrical-ceramics, catalysts, electrical conductors, and chemical intermediates. It is also found in many red candies.

What is Titanium Dioxide Made of?

Titanium is one of the most common metals on Earth, but it does not occur naturally in this primitive form. Titanium Dioxide – Also called Titanium Oxide (IV) or Titanium Dioxide, it is a compound that occurs naturally when titanium reacts with oxygen in the air. Titanium is found as an oxide in the earth’s minerals. It is also found with other elements such as calcium and iron. Its chemical formula is TiO2, meaning that it is composed of one titanium atom and two oxygen atoms (hence dioxide). Has a CAS (Chemical Abstract Services) registration number 13463-67-7. TiO2 is typically considered chemically inert, meaning that it does not react with other chemicals and is therefore a stable substance that can be used in a variety of industries and for a variety of applications.

What are the physical properties of titanium dioxide?

Its melting point is 1.843 ° C and its boiling point is 2.972 ° C, so it is naturally solid and even insoluble in the form of particles in water. TiO2 is also an insulator. Unlike other whites that may appear slightly yellow in light, TiO2 does not have this appearance due to how it absorbs ultraviolet light and appears as pure white.
TiO2 has different qualities depending on whether it is produced as a pigment grade or nanomaterial grade. Both forms are tasteless, odorless. Pigment TiO2 particles are approximately 200-350 nm. Ultra-fine nanoparticles or TiO2 are composed of primary particles smaller than 100 nm. In this grade, titanium dioxide is clear (colorless) and has the properties of scattering and absorbing ultraviolet rays compared to TiO2, the size of larger particles and the degree of pigment.
Importantly, titanium dioxide also has a very high refractive index (ability to scatter light), even higher than diamond. It turns this material into extremely bright materials and ideal materials for using beautiful design. In luminosity, the power of color is unlike any other substance. Stability against heat, light and air against paint degradation in films and plastics. The ability to disperse and absorb ultraviolet rays makes TiO2 an important substance for sunscreen and protects the skin from harmful and carcinogenic UV rays.

What is titanium dioxide used for?

Extremely white color, refractory and UV resistant, makes TiO2 very popular in the industrial and consumer sectors and can be seen in the dozens of products that people use every day. It is used in paints, catalyst coatings, plastics, paper, medicines and sunscreens, and in some lesser-used industries such as packaging, commercial printing inks, other cosmetics, toothpaste, and food.
Paints, coatings and plastics
Until laws changed in the 1920s, most commercial paint manufacturers used white lead, which was highly toxic, as a bleach and did not initially use titanium dioxide because of its high cost. But for now, importing and buying titanium is better than other bleaches because substances like zinc oxide (ZnO), which is used as a white pigment, are not as effective.
Titanium dioxide is currently one of the most commonly used pigments in the world and is the basis for most dyes. It is also found in coatings and plastics. The purchase of Titan in these cases accounts for more than 50% of its global use. Its high refractive index means that as a pigment, it is able to emit visible light. This results in a matte color display and creates a glowing product when placed on a surface or in a product.

Food

In food, TiO2 is used as a pigment and is called E171. In many food products, it acts not only as a bleach, but also as a color and texture enhancer.
Decomposition of environmental pollutants
As a photocatalyst, titanium dioxide can be added to paints, cements, windows and tiles to decompose environmental pollutants. As a nanomaterial, it can also be used as an important DeNOx catalyst in exhaust systems for cars, trucks and power plants, thus minimizing their environmental impact.
Researchers are exploring potential new applications of titanium dioxide in this mold. This includes producing clean energy.

As noted,

the import of titanium in various industries is done in a wide range. Tabarestan Petrochemical Industry Development Company To meet the needs of craftsmen in various fields of importing and selling titanium.