Preparation of Calcium Carbonate Superfine Powder by Calcium Carbide Residue

Calcium carbonate superfine powder with high purity was prepared from calcium carbide residue by a liquid phase process using ammonium chloride as extraction agent and ammonium carbonate agent. The effects of some factors on the reaction were investigated. The calcium carbonate was characterized by X-ray powder diffraction device (XRD) and scanning electron microscopy (SEM). The optimum preparation conditions were determined as follows: the concentration of calcium ion 0.3 mol/L, The mass ratio of ammonium citrate and calcium ion 0.1, temperature of carbonization 10°C The product is calcium carbonate of single crystal structure with the diameter of 40-90 nm.