Hydrated Lime is calcium hydroxide with the chemical formula Ca(OH)₂, appearing as a fine white crystalline powder. It is produced primarily by slaking quicklime (calcium oxide) with water. This chemical reaction yields calcium hydroxide, which is less caustic and easier to handle than quicklime but retains strong alkalinity.
At its core, hydrated lime acts as a strong base, dissociating in water to produce hydroxide ions (OH-) that increase the pH of the medium. This alkalinity enables it to neutralize acids and precipitate dissolved metals or contaminants in wastewater, making it indispensable in water and flue gas treatment. In soil stabilization, the lime chemically reacts with clay minerals, reducing plasticity and improving load-bearing capacity. This is critical for infrastructure in regions with soft or expansive soils.
Its physical properties, such as particle size and moisture content, influence reactivity and handling safety. Hydrated lime typically has a pH around 12.4 when in suspension, indicating strong alkalinity but with significantly less heat generation than quicklime slaking processes.
Performance in applications depends on purity and fineness; higher purity ensures fewer impurities that might interfere with reactions or cause discoloration in treated materials. Zenco Systems Ltd confirms key specifications like purity and grade upon request, helping customers optimize formulations. The powder's relatively low bulk density enables manageable transport and dosing across various industrial uses.
Because hydrated lime readily absorbs moisture and carbon dioxide from the air, it must be stored carefully to maintain effectiveness. It reacts slowly with carbon dioxide to form calcium carbonate, which reduces alkalinity over time. Consequently, shelf life and storage conditions directly impact its performance in critical applications.