The scientific name istitaniaPigment, with molecular formula of TiO2 and relative molecular weight of 79.90 g/mol, naturally exists in titanium ores such as titanium ore and rutile.
White solid or powderyAmphoteric oxideIs the best white pigment.
component
Announce
edit
The chemical composition is titanium dioxide, which is an inert pigment. It is non-toxic, not affected by climate conditions, and has a strong covering power. It is a pigment produced in modern times.The color of pure titanium white dries quickly and turns yellow easily after drying, so it is often mixed withZinc whiteMixed use.Zinc titanium white not only reduces the brittleness of zinc white, but also improves the disadvantage of using titanium white alone.Titanium white and zinc white have the same advantages of non-toxic.Zinc titanium dioxide is a white pigment with a large amount used in China.
Name Origin
Announce
edit
In 1791, the English priest William Gregor went from a magnetic black ore（anatase）White TiO2 samples were prepared for the first time in.Later, German scientist Martin Klaproth came from a reddish brown mineral（rutileThe white TiO2 was also made from the ore, and the white powder was named "Titanic earth" (Titan, Titan is the first generation child of the Earth God in Greek mythology).[1]
application
Announce
edit
Titanium dioxide is an important white pigment and porcelain glaze.For paint, ink, plastic, rubber, paper, chemical fiberWatercolorPigment and other industries.
Titanium white has strong adhesion and is not easy to cause chemical changes. It is always white and the whitest thing in the world.1gtitaniaIt can paint an area of more than 450 square centimeters white.It is one of the most common white pigmentsLithoponeIt is also 5 times white, so it is the best pigment for white paint.The titanium dioxide used as pigment in the world is more than several hundred thousand tons a year.Titanium dioxide can be added to the paper to make it white and opaque, and the effect is 10 times larger than that of other substances. Therefore,Banknote paperAnd art paper will be added with titanium dioxide.In order to lighten the color of plastics and soften the luster of rayon, titanium dioxide is sometimes added.Particularly valuable is that titanium dioxide is non-toxic.It has a high melting point and is used to makeRefractory glass, glaze, enamel, clay, high temperature resistant experimental utensils, etc.
In rubber industry, titanium dioxide is also used as filler of white rubber.
Due to its excellent photocatalytic performance, TiO2 has a wide range of applications in the field of photocatalysis such as photolysis of water, and is praised by scientists as "the most promising photocatalyst for photolysis of water".Semiconductor titaniaphotochemistryIts performance has enabled it to be used in many fields, such as air, water and fluid purification.Doped with carbon or other heteroatomsPhotocatalystIt can also be used for enclosed spaces or areas with scattered light sources.When used in coatings on buildings, pedestrian slabs, concrete walls or roof tiles, they can significantly increase the air pollutants such asnitrogen oxide , aromatics andaldehydeIt has obvious self-cleaning function.Titanium dioxide has goodPhotocatalysisDegradation, can be used fromClean paint。In addition, titanium dioxide has high light reflection performance, which can reduce thesunlightTo "cool the earth".
In addition, it is widely used in productionsunscreen cream, non-toxic, harmless to human body.
FDA regulationstitaniaIt can be used as all food white pigment, and the maximum use amount is 1g/kg Sec. 73.575 titanium dioxide.Titanium dioxide, the pigment additive, can be safely used in general colored food, subject to the following provisions:
(1) The amount of titanium dioxide shall not exceed 1% of the weight of food.
(2) Colored food shall not be used according to the special standards published in Article 401 of the decree, unless there are similar standards that allow the addition of pigments.
(3) For colored food, edible pigment additive titanium dioxide can contain appropriatediluent, as a safe pigment additive, as follows:silicon dioxide, asDispersant additiveThe content shall not exceed 2%.
Production method
Announce
edit
Titanium dioxideThe main production methods of titanium dioxide are sulfuric acid process and chlorination process. The world mainly uses chlorination process. At present, the world's largest producer of titanium dioxide isDuPontThe chlorination method has been used since 1956.In China, sulfuric acid titanium dioxide is mainly used, and chlorinated titanium dioxide is only used by Jinzhou Titanium DioxideMolten saltChlorination, chlorination method is still immature in China.
Major titanium dioxide manufacturers in the world:DuPont, American Ritual Union, Kemeiji, Huntsman, Kronjos
Major titanium dioxide manufacturers in China: Pangang Titanium Industry, Long Mang, and Baililian[2]
Sulfuric acid titanium dioxide
The basic process of sulfuric acid process for titanium dioxide is to firstly use sulfuric acid as acid soluble titanium containing raw materialAcidolysisTo form porous solids, which are obtained by leaching with waterTitanium oxysulfateSolution (weighingblack liquor）After purification and concentration, add waterhydrolysisForming whiteMetatitanic acidHigh temperature after sedimentation and purificationcalcinationYou can getTitanium dioxideThe final product can be obtained by calcined titanium dioxide and salt treatment coating.
Compared with titanium chloride, its raw materials are cheap and easy to obtain, with less investment, mature process and simple equipment, but its production process is long and there are many processes,Three wastesMore pollution,Intermittent operationThe labor intensity is high, and the product quality is slightly poor.
Chlorinated titanium dioxide
The basic process of chloridizing titanium dioxide is to firstly use titanium raw materials andPetroleum cokeMix in a certain proportion and then feed inchlorineChlorinationTitanium tetrachloride, titanium tetrachloride is used after purificationoxygenOxidation will result inTitanium dioxideThe chlorine gas returns to continue chlorination, and the titanium dioxide obtained by oxidation also needs salt treatment, coating and other processes to get the final product.
Compared with sulfuric acid process titanium dioxide, the process flow is shorter and the waste discharged is less, but it has high requirements for raw materials, serious equipment corrosion, and easy to block the reactor in the oxidation stage, which is technically difficult,continuous production , operation requires complex control system.
