obtención y caracterización de la fase vaterita metaestable del carbonato de calcio catalizada por ag-mg a temperatura ambiente | obtaining and characterization of the metastable vaterite phase of calcium carbonate catalyzed by ag-mg at room temperature

The crystallization of CaCO3 was performed with CaCl2 and (NH4)2CO3 as sources of Ca2+ and CO32- ions, respectively, and promoted by a catalyst of Ag-Mg LDH at room temperature. It was demonstrated by X-ray diffraction that the catalyzed reaction promoted the formation of polymorphs of CaCO3 calcite and vaterite, the latter with a percentage ranging 20% in the cases of variation of the concentration of Ca2+ and CO32- ions or varying of catalyst. By Scanning Electronic Microscopy it was tested out the morphologies, rombohedral for calcite and spherical arrangement of layers for vaterite. The highest amount of vaterite was obtained using 5 mmol of CaCl2, 21.1 mmol of (NH4)2CO3 and 0.1 g of the catalyst.