Method for preparing cubic precipitated calcium carbonate

[0022] Example 1

[0023] (1) Add 2500 grams of quicklime to 40 liters of water at 48°C and stir for 30 minutes to prepare a calcium hydroxide slurry, which is then passed through a 200-mesh sieve for use; the concentration of the calcium hydroxide slurry obtained is 61.3 grams/liter;

[0024] (2) Add the above 30 liters of calcium hydroxide slurry to the jacketed reaction vessel equipped with a dispersing paddle; turn on the dispersing slurry (linear speed 5.6 m/s), and fill the jacket with circulating cooling water to make the reaction vessel The calcium hydroxide slurry was cooled to 11.3°C, and then filled with carbon dioxide at a rate of 29.4 liters/min. At the same time, the temperature of the slurry in the reaction vessel was controlled at 10-25°C until the pH value of the slurry in the reaction vessel reached 6.2; Aqueous slurry of cubic precipitated calcium carbonate, products such as figure 1 Shown.

[0025] by figure 1 It can be seen that calcium carbonate is cubic particles with uniform particle size and closely packed together.

[0026] Example 2

[0027] (1) Add 1,900 grams of quicklime to 30 liters of water at 48°C and stir for 30 minutes to prepare a calcium hydroxide slurry, which is then passed through a 200-mesh sieve for use; the concentration of the obtained calcium hydroxide slurry is 52.9 grams/liter;

[0028] (2) Put the above 28 liters of calcium hydroxide slurry into a jacketed reaction vessel equipped with a dispersing paddle; turn on the dispersing slurry (linear speed 5.6 m/s), and fill the jacket with circulating cooling water to make the reaction vessel The calcium hydroxide slurry was cooled to 15.2°C, and then filled with carbon dioxide at a rate of 23.7 liters/min. At the same time, the temperature of the slurry in the reaction vessel was controlled at 14-22°C until the pH value of the slurry in the reaction vessel reached 6.2; Aqueous slurry of cubic precipitated calcium carbonate, products such as figure 2 Shown.

[0029] by figure 2 It can be seen that calcium carbonate is cubic particles with uniform particle size and closely packed together.

[0030] Example 3

[0031] (1) Add 2506 grams of quicklime to 30 liters of water at 43°C and stir for 30 minutes to prepare calcium hydroxide slurry, which is then passed through a 200-mesh sieve for use; the obtained calcium hydroxide slurry concentration is 59.2 grams/liter;

[0032] (2) Put the above 28 liters of calcium hydroxide slurry into a jacketed reaction vessel equipped with a dispersing paddle; turn on the dispersing slurry (linear speed 5.6 m/s), and fill the jacket with circulating cooling water to make the reaction vessel The calcium hydroxide slurry was cooled to 16.8°C, and then filled with carbon dioxide at a rate of 26.5 liters/min. At the same time, the temperature of the slurry in the reaction vessel was controlled at 16-25°C until the pH value of the slurry in the reaction vessel reached 6.0; the reaction was completed Aqueous slurry of cubic precipitated calcium carbonate, products such as image 3 Shown.

[0033] by image 3 It can be seen that calcium carbonate is cubic particles with uniform particle size and closely packed together.