用蛇纹石硫酸铵焙烧法制备超细氢氧化镁的研究

摘要

Calcining serpentine with ammonium sulfate to extract magnesium for preparaion of ultrafine magnesium hydroxide. This paper studies the effect of temperature on the performance of the preparation of ultrafine magnesium hydroxide, which come to the conclusion the appropriate reaction temperature is 40℃. The results show that superfine magnesium hydroxide particles occur agglomeration and have large specific surface area. In order to overcome the agglomeration of the magnesium hydroxide and decrease the surface area, the magnesium hydroxide hydrothermal reaction is carried on and the appropriate condition of hydrothermal time is 3 h. Through analysis of their chemical composition, particle size distribution, surface area and SEM, it shows that after the hydrothermal reaction magnesium hydroxide specific surface area is 13.79 m2/g, the content of MgO is 68.23%, and has good crystalline form.%　　以蛇纹石为原料，通过硫酸铵焙烧法提取蛇纹石中的镁，并制备超细氢氧化镁。研究了温度对制备超细氢氧化镁性能的影响，得出适宜反应温度为40℃，SEM测试结果表明，制备的超细氢氧化镁颗粒间发生了较多团聚，比表面积较大。为克服氢氧化镁的团聚现象，降低比表面积，将氢氧化镁在反应釜中进行水热反应，得出适宜水热时间为3 h。化学分析以及粒度、比表面积、SEM测试结果表明，水热反应后氢氧化镁比表面积为13.79 m2/g，MgO含量为68.23%，晶型较好。