Nucleation, crystallization and growth of CaCO_3 grains on lauric acid template during micropore dispersion carbonation

摘要

Nano CaCO_3 powder was prepared by dispersing CO_2 into Ca(OH)_2 slurry via a micropore plate with different addition of lauric acid as template, and the nucleation, crystallization and growth of CaCO_3 grains on lauric acid template were investigated in the present work. The polymorph and morphology of CaCO_3 particles was characterized by XRD and TEM, respectively. XRD patterns indicated that calcite is the only crystalline phase for different addition of lauric acid. From TEM images, decreased particle size and improved dispersity were found when lauric acid was added and the best dispersity was at 2.5 wt% of lauric acid. The mechanism of nucleation, crystallization and growth of CaCO_3 grains on lauric acid template were also proposed.