Precipitated Calcium Carbonate (PCC) is a refined, synthetic form of calcium carbonate (CaCO) produced through a controlled chemical reaction. Unlike ground calcium carbonate (GCC), which is derived from natural limestone, PCC is manufactured for high purity and specific particle size and shape.
Production Process
PCC is typically produced by:
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Calcining limestone (CaCO) to produce quicklime (CaO).
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Hydrating quicklime to form calcium hydroxide (Ca(OH)).
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Reacting calcium hydroxide with carbon dioxide (CO) to precipitate fine calcium carbonate crystals:
Ca(OH)2+CO2CaCO3+H2O\text{Ca(OH)}_2 + \text{CO}_2 \text{CaCO}_3 + \text{H}_2OCa(OH)2+CO2CaCO3+H2O
Key Characteristics
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High purity
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Fine and uniform particle size
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Controlled crystal morphology (e.g., scalenohedral, rhombohedral, spherical)
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High brightness and whiteness
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Good dispersion in various media
Applications
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Paper industry as a filler and coating pigment to improve brightness, opacity, and surface smoothness.
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Plastics and rubber as a reinforcing and cost-reducing filler.
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Paints and coatings for improved gloss and opacity.
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Pharmaceuticals and food as a calcium supplement and antacid (when food-grade).
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Cosmetics for abrasiveness and bulking.