高纯度硅酸三钙的实验室高效制备及其表征

Synthesization and Characterization of High Purity C_(3)S Mineral in Laboratory

硅酸三钙(Ca_(3)SiO_(5),简写为C_(3)S)作为水泥熟料中最重要组成矿物,研究其水化行为是揭示水泥基材料水化机理的重要途径。本文以CaCO_(3)粉末、气相SiO_(2)粉末为原材料制备C_(3)S,通过球磨混合、干燥成型、高温煅烧、冷淬等主要步骤,最后研磨得到高纯度C_(3)S矿物粉末。对制备的矿物进行定量XRD、乙二醇滴定、SEM、TEM等分析表征,结果表明以本方法制备的C_(3)S矿物含量达到96%,且杂质(主要是f-CaO)含量低于0.5%;本方法材料易得,制备过程得以简化,产量大幅增加(1kg/周)。

As one of the major important components of cement,alite(C_(3)S)plays a critical role in the hydration of cement.The investigation of C_(3)S characteristics can help reveal hydration mechanism of cement-based materials.In this study,high purity C_(3)S was synthesized in laboratory using analytical grade CaCO_(3) and SiO_(2) powders as raw materials.After being fully mixed in a ball mill with water,they were put into a mold and dried in a vacuum oven.Then the mixture was sintered in a high-temperature muffle furnace to corresponding temperature and time,then rapidly cooled to room temperature.The synthesized C_(3)S minerals were characterized by ethylene glycol titration,XRD,QXRD,and SEM analyses.The results showed that the C_(3)S mineral prepared by this method has significant characteristic peaks in the XRD spectrum,high purity in QXRD spectrum,and very little impurity such as f-CaO.The morphology of the minerals and hydration products were characterized using SEM and TEM analyses respectively.Comparing to other existing syntheses,the proposed method has several advantages including easy availability of high-quality raw materials,simplified processing,high purity and high productivity.