Specific Surface Area: Depending On The Particle Size, The Specific
Surface Area Is Between 40-100m²/g Zinc Oxide
Preparation methods and common applications of zinc oxide
Zinc oxide can be prepared by a variety of methods, including
calcination, hydrothermal, sol-gel and solution methods. Each
method has its own characteristics and scope of application, and
the appropriate preparation method can be selected according to
specific needs. The calcination method is suitable for large-scale
industrial production, while the sol-gel method can obtain zinc
oxide powder with smaller particles and uniform distribution. The
application of zinc oxide in the fields of environmental protection
and new energy is also becoming more and more extensive, such as
photocatalytic degradation of organic matter, solar cells, etc.
With the advancement of science and technology and people's pursuit
of high-quality life, the application scope of zinc oxide will
continue to expand, and its importance will become increasingly
prominent. In the future, through continuous research and
innovation, zinc oxide is expected to create a better living and
working environment for us.
Specifications
Item | Specification |
Chemical Formula | ZnO |
Molecular Weight | 81.38 g/mol |
Appearance | White powder |
Purity | ≥99.9% |
Particle Size | 20-50 nm (Nanometer) |
Specific Surface Area | 20-30 m²/g |
Melting Point | 1975°C |
Density | 5.606 g/cm³ |
Solubility | Insoluble in water |
Calcination method
1.Direct calcination method:
Calcine zinc powder, zinc ore or zinc-containing waste slag at high
temperature in the air to oxidize it to produce zinc oxide.
This method is suitable for processing raw materials with high zinc
content and can be produced on a large scale in industry.
For example, zinc ore or zinc ash is mixed with coal and lime in a
certain proportion and crushed, then pressed into balls by a coal
briquette machine, dried and smelted in a zinc oxide furnace, and
then reduced, oxidized and cooled to obtain zinc oxide products.
2.Zinc carbonate calcination method:
Calcine zinc carbonate at high temperature to decompose and
generate zinc oxide and carbon dioxide.
The reaction equation is: ZnCO3===ZnO+CO2↑.
3.Zinc hydroxide calcination method:
Calcine zinc hydroxide at high temperature to decompose and
generate zinc oxide and water.
The reaction equation is: Zn(OH)2===ZnO+H2O (Note: This reaction
usually requires higher temperature and longer reaction time in
actual operation, and the equal sign in the reaction equation
should be understood as indicating the direction of the reaction).
Hydrothermal method
Zinc ions react with hydroxides such as sodium hydroxide or
ammonium hydroxide to produce zinc hydroxide precipitate.
The zinc hydroxide precipitate is then treated under high
temperature and high pressure for a certain period of time to
obtain zinc oxide.
Sol-gel method
React an appropriate zinc salt with ammonia or other alkaline
solution to generate zinc hydroxide sol.
After appropriate treatment, zinc oxide colloid is obtained.
Finally, the zinc oxide colloid is dried and calcined to obtain
zinc oxide powder.
Sol-gel method
React an appropriate zinc salt with ammonia or other alkaline
solution to generate zinc hydroxide sol.
After appropriate treatment, zinc oxide colloid is obtained.
Finally, the zinc oxide colloid is dried and calcined to obtain
zinc oxide powder.
Indirect method (also known as French method)
The zinc ingot obtained by electrolysis is placed in a
high-temperature crucible, heated to 600-700℃ to melt, and then
evaporated at a temperature above 1000℃ to form zinc vapor.
The zinc vapor is oxidized by oxygen in the air to produce zinc
oxide, accompanied by a decrease in temperature.
The zinc oxide particles are collected in a dust collection chamber
through a cooling conveying pipe, and the fine particles are
captured in a bag after cyclone separation to obtain the finished
zinc oxide.
Wet method
Zinc ash is reacted with sulfuric acid to produce zinc sulfate.
Zinc sulfate is reacted with sodium carbonate and ammonia water
respectively to obtain zinc carbonate and zinc hydroxide as raw
materials.
When zinc carbonate is used as the raw material, zinc oxide is
obtained by washing, drying, calcining and crushing.
When zinc hydroxide is used as the raw material, zinc oxide is
obtained by washing, precipitation, drying, calcining, cooling and
crushing.
