Synthesis of highly dispersed calcium carbonate at excessive pressure of carbon dioxide

The purpose of the paper was to find out how the conditions for the synthesis of calcium carbonate, having the patent of the Russian Federation No. 2489355, affect the average particle size and their size distribution. The process was carried out in a transparent 1 liter plastic reactor; the excess pressure of carbon monoxide (IV) was quickly created and sharply dropped in no longer than 90 seconds at a temperature of 25ºC and in no longer than 6 minutes at 6ºC. The obtained highly dispersed carbonate was studied microscopically, and a histogram of the particle size distribution was constructed. The optimum process time at room temperature is 60 seconds. The resulting product is characterized by a narrow particle size distribution with a maximum of about 2.5 µm. The particle size reduction occurs when either the reaction time or the temperature decreases. Aggregate stability of the suspension depends on the molar ratios of calcium hydroxide and carbon monoxide (IV). The activation energy of the reaction is 59 kJ / mol. (paper)