Review and Recalculation of Growth and Nucleation Kinetics for Calcite, Vaterite and Amorphous Calcium Carbonate

The precipitation of calcium carbonate is well studied in many fields of research and industry. Despite the fact that, or perhaps because of the fact that, it is well studied in many fields, different approaches have been used to describe the kinetics of the precipitation process. The aim of this study was to collect and compare the data available in the literature and find a consistent method to describe the kinetics of growth and nucleation of the various polymorphs of calcium carbonate. Inventory of the available data showed that a significant number of the literature sources were incomplete in providing the required information to recalculate the kinetic constants. Using a unified method, we obtained a unique set of parameters to describe the kinetics for growth for calcite, vaterite and amorphous calcium carbonate (ACC) and nucleation for vaterite and ACC. Recalculation of the kinetic constants demonstrated that calcite confirmed there are two growth mechanisms within one polymorph, namely pure spiral growth and spiral growth mixed with surface nucleation. The spiral growth does not show second-order growth, which is typically attributed to it. Re-evaluation of the available nucleation data confirmed the suggested existence of a second pure ACC polymorph with a solubility product between 10(-5.87) and 10(-5.51) mol(2) kg(w)(-2).

Automated summary

The study aimed to collect and compare literature data to describe the kinetics of growth and nucleation of different forms of calcium carbonate. Utilizing a unified method, a unique set of parameters was obtained for describing the kinetics of growth for calcite, vaterite, and amorphous calcium carbonate, as well as nucleation for vaterite and amorphous calcium carbonate. Recalculation of kinetic constants revealed two growth mechanisms within calcite and confirmed the suggested existence of a second pure amorphous calcium carbonate polymorph.