Calcium Carbonate Crystallization in the Presence of Aspartic Acid

Abstract

The kinetics of vaterite (CaCO3) crystallization on calcite in the presence of aspartic acid was investigated by the constant composition technique. The presence of aspartic acid in the supersaturated solution stabilizes this calcium carbonated polymorph possibly through the development of active growth sites, which should show chemical and structural affinity to this mineral phase. The number of ions forming the critical nucleus was n* = 4, and a surface energy of 31 mJ m-2 for the growing phase was estimated. The apparent order was found to be 1.75 ± 0.25, indicative for a surface diffusion controlled mechanism.