Zinc oxide. Properties and applications

Zinc oxide (also known as zinc oxide) is an amphoteric oxide, a crystalline colorless powder, yellowish with gradual heating and subliming at 1800 degrees. Insoluble in water. The degree of oxidation of zinc in this compound is 2. The chemical formula is ZnO. This substance is important for humanity. It has a multifaceted effect on the human body.

Zinc oxide: physical properties

1. The thermal conductivity is 54 W / (m * K).
2. It is a semiconductor with a band width of 3.3 eV.

Chemical properties of zinc oxide

1. Reacts with acids. In this case, salts are formed.
2. Reacts with alkalis to form tetra-, tri- and hexahydroxyzincates.
3. This substance is dissolved in an ammoniacal aqueous solution. In this case, a complex ammonia is formed.
4. When fusing with oxides and alkalis, the zinc oxide forms zincates.
5. When fused with silicon and boron oxides, the zinc oxide forms silicates and vitreous boards.

How is the zinc oxide (ZnO)

Zinc oxide can be obtained in several ways:

• From the natural mineral zincite;
• By burning zinc vapor (Zn) in oxygen (O) - this is the so-called "French process";
• By thermal decomposition of the following compounds: Zn (OH) 2 hydroxide, Zn (CH3COO) 2 zinc acetate, Zn (NO3) nitrate, ZnCO3 carbonate;
• At oxidizing firing of ZnS (zinc sulphide);
• Hydrothermal synthesis;
• By extraction from the slimes and dust of metallurgical plants. Of particular importance are those plants that specialize in scrap metal, containing a significant proportion of iron galvanized.

Application of zinc oxide

Zinc oxide is used in the production of rubber, paper, some plastics, rubber products, artificial leather, electric cables, glass, ceramics, cosmetics (sunblock, various beauty treatments) and perfumes. It is used as an activator for the vulcanization of various rubbers, a catalyst for the synthesis of organic matter - methanol, the vulcanizing agent of chloroprene rubbers, pigment and filler in production. Previously, zinc oxide was needed as a white pigment in the production of enamels and paints, but now it is completely replaced by TiO2 (titanium dioxide is non-toxic). Zinc oxide was also widely used in the paint, tire and oil refining industries.

Zinc oxide has also become widespread in medicine and pharmaceutics (preparations "Zinc ointment", "Sudocrem", "Pasta Lassara"). It is used in the composition of antiseptic ointments, in the form of powders. In practice, it is used to create bactericidal ceilings and coatings in hospitals, self-cleaning surfaces. With the help of zinc oxide, toothpastes and cements for therapeutic dentistry are produced . It used to be used on an industrial scale for photocatalytic water purification.

Also, the substance we are considering is used in the production of paints and glasses based on liquid glass, as one of the components of the rust remover and as an additive to animal feed. In addition, the powder of this substance is a promising material as a working medium for powdered lasers. On the basis of zinc oxide, a blue colored light was created. And some nanostructures (for example, thin films) based on this substance can be used as biological or gas sensitive sensors.

What effect does zinc oxide have on a person?

This chemical compound is low toxic. In the air of working rooms, MPC should be no more than 6 mg per cubic meter. Dust of zinc oxide can form when firing brass products. When working with zinc oxide, do not let the substance enter the eyes. Medicines with zinc oxide should be used only as directed by a doctor.