Effect of Magnesium Ion on the Precipitation of Hollow Calcium Carbonate by Bubble Templating Method

摘要

Hollow calcium carbonate (CaCO_3) particles were synthesized by bubbling CO_2 in the solution of calcium chloride (CaCl_2) with the presence of ammonia at room temperature. In this method, CO_2 bubble, besides as reactant, has an important role as a template for forming hollow particles. The precipitation was carried out by controlling the precipitation condition, such as pH, flow rate and additives. Hollow calcium carbonate particles were precipitated with the major crystal phase of vaterite. An interesting finding is that magnesium ion (Mg~(2+)) can suppress the transformation of vaterite to calcite by inhibiting the growth of the calcite.