Light calcium powder, also known as light calcium carbonate, is made by burning limestone and other raw material segments to produce lime (the main component is calcium oxide) and carbon dioxide, and then adding water to digest the lime to produce lime milk (the main component is Calcium hydroxide), and then add carbon dioxide to carbonize the milk of lime to form calcium carbonate precipitate. Finally, it is dehydrated, dried and crushed by a lime mill, or first use sodium carbonate and calcium chloride to perform a metathesis reaction to form calcium carbonate precipitate. , and then obtained by dehydration, drying and crushing. Since the settling volume of light calcium powder (2.4-2.8mL/g) is larger than that of heavy calcium powder (1.1-1.4mL/g), it is called light calcium powder.
The chemical formula of calcium carbonate is CaCO3. Calcium carbonate reacts with all strong acids to generate water and corresponding calcium salts (such as calcium chloride CaCl2), and at the same time releases carbon dioxide; at normal temperature (25°C), The concentration product of calcium carbonate in water is 8.7×1029, the solubility is 0.0014, the pH value of calcium carbonate aqueous solution is 9.5~10.2, and the pH value of air-saturated calcium carbonate aqueous solution is 8.0~8.6. Calcium carbonate is non-toxic, odorless and non-irritating. It is usually white and has a relative density of 2.7 to 2.9. The sedimentation volume of light calcium carbonate is more than 2.5ml/g, and the specific surface area is about 5m2/g. Light calcium carbonate has fine particles, rough surface, and large specific surface area, so its oil absorption value is high, about 60-90ml/100g.
Powder characteristics of light calcium powder:
a. The particle shape is regular and can be regarded as a monodisperse powder; b. The particle size distribution is narrow; c. The particle size is small.