Calcium hydroxide is a white powdery solid, odorless and strongly alkaline. It readily absorbs carbon dioxide (CO₂) from air to form calcium carbonate. It is slightly soluble in water, and its aqueous solution is strongly alkaline (pH ≈ 12.4) with corrosive properties.

1. Construction: Bricklaying, plastering, lime mortar, soil stabilization

2. Environmental protection: Wastewater treatment (neutralization of acidic wastewater, phosphorus removal, hard water softening), flue gas desulfurization

3. Chemical industry: Production of bleaching powder, propylene oxide, calcium salts, leather tanning, rubber filling

4. Agriculture: Soil improvement, acid neutralization, pesticide adjuvant, disinfection and sterilization

5. Food / Pharmaceutical: Food additive (acidity regulator, coagulant), pharmaceutical intermediate