管式气体分散式反应器制备纳米碳酸钙

Preparation of nano-sized calcium carbonate by tubular gas dispersing-type reactor

以石灰石为原料，利用管式气体分散式反应器新工艺制备出了粒径30～70nm的碳酸钙粉体。采用X射线衍射（XRD）、扫描电镜（SEM）、粒度分布仪及红外光谱仪（Fr-IR）等测试手段，对产品的物相、形貌和粒度分布进行了表征。X射线衍射表明产物为六方晶系方解石型碳酸钙并且产品结晶性能良好；扫描电镜及粒度分析表明粒度大小均匀、分散性良好；红外光谱表明改性后硬脂酸钠已吸附在碳酸钙表面，碳酸钙颗粒基本呈单分散状态。管式气体分散式反应器制备纳米碳酸钙粉体的优点是工艺简单，操作容易，原料易得，生产的产品粒径小，粒度分布窄，易于工业化生产。

Using limestone as the raw material, the nano - sized CaCO3 powder with particle size of 30 ～ 70 nm was prepared by a new process i. e. tubular gas dispersing - type reactor. The crystal structure, morphology and particle size distribution were characterized by X - ray diffraetometer （ XRD ） , scanning electron microscope （ SEM ） , particle size analyzer and FF - IR. XRD result showed that the product was hexagonal system calcite - type CaCO3 with good crystallization properties ; SEM and particle size analyzer showed that the product had even particle size and good dispersibilty; FF - IR showed that the sodium stearate had been absorbed on the surface of the modified CaCO3 and the CaCO3 particles was basically in the state of monodisperse. The advantages of the tubular gas dispersing - type reactor were characterized by simple process and operation, easily - gained raw material, small particle size of products, narrow size distribution and easy - to - industrialize.