SUBSTANTIALLY SPHERICAL VATERITE, AND PRODUCTION METHOD

摘要

Disclosed is a substantially spherical vaterite of a spheroidal shape having two hollows positioned opposite each other and the particle size distribution factor less than 0.5. There is further disclosed a method for producing vaterite wherein a mixture of particles containing calcium in oxide and/or hydroxide form is treated in a reactive medium containing an acid salt of an organic amine in order to transform the calcium in soluble salt form and to obtain a medium whose pH, the so called process pH, has a value higher than 10. CO2 is introduced in the medium subjected to stirring until the pH of the medium reaches a so called saturation pH of a value close to 0.83 x process pH, and CO2 is introduced at a flow rate lower than 50g CO2/hour/litre in the medium so as to form the substantially spherical vaterite.