Preparation of Aragonite Calcium Carbonate Crystal Whiskers by Gas-liquid Method and Its Influencing Factors Study

The morphology and influencing factors of CaCO3 crystal whiskers were investigated by means of gas-liquid method in the system of MgCl2-Ca(OH)2-CO2. The results indicate that the aragonite calcium carbonate (CaCO3) crystals thus prepared are characteristic of a nice external form with a rather satisfactory high aspect ratio and evenly-distributed whiskers. The CaCO3 crystals were then characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and Fourier transform infrared (FT-IR) spectroscopy. The optimum reaction conditions of them are as follows: reaction temperature is at 80 ℃, CO2 flow rate is 5 mL/min, stirring speed is 250 r/min, and concentration of MgC12is 0.4 mol/L.