Preparation Of CaSiO₃Powder By Molten Salt Synthesis

CaSiO3called wollastonite in mineralogy is widely used as additive in materials, such as the plastics, rubber, metallurgy, ceramic, construction material, and so on. In present, production of CaSiO3is a high energy consumption process in the industry.In the present, as a solution, molten salt synthesis is proposed. Influence of temperature, time, the sort of the molten salt on the CaSiO3prepared were investigated in experiments. The properties of products were characterized by SEM, XRD, EDS, TG/DTA. Granularity of CaSiO3powder was measured by the laser powder granularity measure. The process was explored from600℃to900℃in CaCl2/NaCl; The results showed that monoclinic CaSiO3whiskers have been achieved at700℃. According to documents(the most lowest temperature was over800℃CaSiO3), the reaction temperature was greatly low; Monoclinic CaSiO3whiskers have been also achieved in CaCl2when the temperatures were from800℃to900℃; diameter of products is smaller in CaCl2/NaCl than that of in CaCl2; products in CaCl2/NaCl was smoother than that of in CaCl2. NaCl affected the growth of whiskers, and improve the transfer conditions. The factor of temperature was most important effect factor on the growth of CaSiO3whiskers than other conditions in process. It is easy to deduce branching and knot at high temperature. Powder granularity decrease with the temperature. The products have integrated micro-topography, the uniform diameter and smooth surface. It is a new preparation process of CaSiO3whiskers.