高纯硅酸三钙矿物的制备及其早期水化特性

Preparation of High Purity 3CaO·SiO_2 and Its Early Hydration Properties

为制备高纯度硅酸三钙矿物并研究其早期水化特性,采用溶胶-凝胶法制备硅酸三钙单矿,通过X射线衍射、扫描电镜、差热分析以及乙二醇-乙醇法、激光粒度分析等测试手段,研究制备高纯硅酸三钙的最佳工艺以及其早期水化特性。结果表明:制备高纯硅酸三钙的最佳预烧温度为540℃,最佳煅烧温度为1 450℃并保温12 h;制备的硅酸三钙样品中游离CaO质量分数为0.2%,平均粒径为9.67μm,比表面积为15.16 cm^2/kg;硅酸三钙具有良好的水化活性,早期水化产物C-S-H微观形貌的演变规律是花瓣状—片状—片层纤维,另一水化产物Ca(OH)_2发生了择优取向,沿着(001)晶面定向生长。

In order to study the preparation of 3CaO · SiO2 （C3S） and its hydration process ,the single mineral of C3S was prepared by sol - gel method and the optimum technological conditions of preparing C3 S and its hydration properties were explored by XRD, SEM, DSC - TG, ethanediol - alcohol method and laser particle size analyzer. The results show that the optimal presintering temperature is 540℃ and the optimal sintering schedule is holding 12 h at 1 450 ℃. The mass fraction of free CaO in C3 S is 0.2% with a mean diameter of about 9.67 μm, the specific surface area is 15.16 cm^2/kg. The single mineral of C3 S has high hydration activity, the micro-morphology of early hydration product C-S-H changes from the petal to sheet to laminar fiber, the other hydration product Ca（OH） 2 occurs the directional growth towards the （001） crystal plane.