Zinc powder.

One important product of deeper zinc processing is zinc powder, and the smaller fraction is dust. Zinc powder (dust) is a thin bluish-gray powder, almost pure zinc (95-98%) with a small amount of impurities.

Table 1. Chemical composition of zinc powders, %

Notes:

1. PCI4 powder used for the production of sodium hydrosulfate must contain no more than 0.06 % Cd.
2. By agreement of the manufacturer with the consumer in zinc powder grade PT5 allowed cadmium content not more than 2%.
3. In the zinc powder of all brands used in the pharmaceutical industry, in the chemical (for the production of benzidine and its analogues), the content of the residue insoluble in hydrochloric acid diluted 1: 1 should not exceed 0.05%. The solution obtained in determining the insoluble residue must be colorless.
4. The content of copper, tin, arsenic and antimony in the powder of all brands, the manufacturer determines periodically once a month.

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*insoluble in hydrochloric acid diluted 1:1.

Table 2: Granulometric composition of zinc powders

Notes:

1. In chick powder used for the production of benzidine and its analogues, the residue content on the grid No. 016 K should not exceed 0.1%.
2. It is allowed to manufacture zinc powder grade PTS6 with a fraction content of -0.63 + 0.16 mm, not less than 94%.

Intake of zinc powder.

Zinc powder It is a multifaceted product with many applications.
Zinc dust is introduced into tread coating materials (soils and paints), for painting ships, bridges and other structures operating in harsh atmospheric conditions. Good anti-corrosion properties have coatings, which contain a mixture of zinc dust and zinc oxide.
Paradoxically, but also in the production of zinc by hydrometallurgical method, zinc dust is used - to clean a solution of zinc sulfate from copper and cadmium.

Zinc powder used chemical industry as a filler, in the production of fluoroplasty and other polymers, lubricants.

Pyrotechnics. Zinc dust is used to obtain the blue color of the flame.

Zinc powder is used battery. Disposal of the service life of HIT has caused certain environmental problems. The production of HIT uses mercury, cadmium, antimony and other toxic chemical elements. Collecting and processing a large number of current sources is difficult. This led to the search for new materials and the development of current sources free of toxic elements.

Zinc dust is used production of rare and noble metals. In particular, zinc dust displaces gold and silver from cyanide solutions. Without zinc powder, it would not be possible to extract precious metals from a number of ore materials.
The two most promising areas of application of zinc powder in the field of metal protection against corrosion, which are developing most actively - zinc-filled paints and thermal diffusive galvanizing.