The influence of xanthan on the crystallization of calcium carbonate

Abstract Calcium carbonate (CaCO 3 ) was crystallized in xanthan (XC) aqueous solutions. The CaCO 3 particles were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and thermogravimetry analysis (TGA) methods. The concentrations of XC, Ca 2+ and CO 3 2− ions and the ratios [Ca 2+ ]/[CO 3 2− ] and [Mg 2+ ]/[Ca 2+ ] show evident influence on the aggregation and growth of CaCO 3 particles. The presence of Mg 2+ ions influences not only the morphology, but also the polymorph of CaCO 3 .