Study on the Effect of Magesium Ion on the Crystal Phase of Calcium Carbonate

Morphology and crystal phase of calcium carbonate, which formed with the presence of Mg2+, were characterized by SEM and XRD. The effect of Mg2+ on crystallization and crystal phase of calcium carbonate was studied. The results showed that the crystal phase of calcium carbonate were mainly calcite and aragonite and the content of aragonite was higher after adding Mg2+ to the blank solution. With the increase of Mg2+ concentration, the content of aragonite increased. The calcium carbonate crystals grain became more fine and the content of aragonite was higher by synergistic treatment between Mg2+ and magnetic field. There was a strong inhibitory effect on calcite when the concentration of Mg2+ was more than 0.50mmol.L-1. The calcite could be transformed into aragonite in the presence of Mg2+ in solution.