Calcium oxide, commonly known as slaked lime or lime, is an inorganic compound with the chemical formula CaO and a molecular weight of 56.08. It is usually produced by calcining limestone (calcium carbonate) at high temperatures and is one of the most fundamental raw materials in industrial production.

CAS Number: 1305-78-8

EINECS Number: 215-138-9

Molecular formula: CaO

Appearance: Usually it is a white or off-white amorphous powder. When impurities are present (such as iron, magnesium), it may appear grayish-white, light yellow or gray.

Physical and chemical parameters

Product features

• Calcium oxide possesses remarkable physical and chemical properties, which form the basis for its application in various industries:

• Highly alkaline: It is a highly alkaline substance. The aqueous solution (calcium hydroxide) is highly alkaline and corrosive.

• Hydration exothermic reaction: When exposed to water, it undergoes a violent chemical reaction to form calcium hydroxide and releases a large amount of heat. This property is utilized in "self-heating" products.

• Hygroscopicity and reactivity: Sensitive to moisture, it readily absorbs moisture from the air (forming slaked lime) and carbon dioxide (forming calcium carbonate), thus requiring sealing and moisture-proof storage.

• Corrosiveness: Dust has a strong irritating and burning effect on the eyes, respiratory tract and skin. Protective equipment must be worn during operation.

Core advantage

• The raw materials are widely sourced: using limestone as the raw material, there is a rich global reserve and the acquisition cost is low.

• High reaction efficiency: As a desiccant or neutralizer, it has a fast reaction speed and strong water absorption capacity.

• Environmental-friendly economy: It has high efficiency in fields such as flue gas desulfurization and wastewater treatment, and has a significant cost advantage compared to caustic soda (sodium hydroxide).

• Versatile applications: It can be used as a basic building material, or as a raw material for fine chemicals, with application levels ranging from heavy industry to light industry.

Main purpose

Calcium oxide is a "multifunctional" industrial cornerstone and is widely applied in the following fields:

Architecture and Building Materials:

• It is the core raw material for manufacturing cement, lime slurry and lime bricks.

• It can be used as a rapid setting agent for cement and is suitable for special engineering requirements.

Environmental Protection Field:

• Flue gas desulfurization: Used for flue gas desulfurization treatment before emissions in power plants and other facilities.

• Wastewater treatment: Adjust the pH value of the wastewater, precipitate heavy metal ions, and use it as a stabilizer for sludge.

• Soil remediation: Improving acidic soil (using agricultural calcium fertilizer).

Chemical Engineering and Metallurgy:

• Desiccant: Used in laboratories and industries for drying alcohols, ammonia, and for detecting moisture in hydrocarbons.

• Metallurgical flux: Used in steel smelting for slag-making, to remove impurities such as sulfur and phosphorus.

• Production raw materials: Used for manufacturing calcium carbide (calcium carbide), soda ash, bleaching powder, calcium hydroxide and various calcium salts.

Other applications:

• Desiccant: Used for moisture-proof packaging and boiler shutdown protection agent (to prevent metal surface corrosion).

• Food/Pharmaceuticals: Can be used as a drug carrier or a food additive (processing aid).

• Special materials: High-purity calcium oxide is used in the epitaxy and diffusion processes of semiconductor production.