水菱镁矿制备不同形貌纳米氧化镁的研究  

Study on the Preparation of Nanometer Magnesia with Different Morphologies from Hydromagnesite

作　　者：黄建翠 凌观爽 宗俊 HUANG Jian-cui;LING Guan-shuang;ZONG Jun(School of Chemistry and Molecular Engineering,East China Normal University,Shanghai 200241,China)

机构地区：[1]华东师范大学化学与分子工程学院,上海200241

出　　处：《盐科学与化工》2020年第8期11-18,共8页Journal of Salt Science and Chemical Industry

摘　　要：以天然水菱镁矿为原料,在“煅烧—水化—煅烧”的简单工艺路线下,通过控制煅烧温度和时间,制备了具有不同形貌的纳米氧化镁,且实验过程中无需加入任何试剂。研究了不同煅烧温度、煅烧时间对氧化镁形貌、结晶度、晶粒尺寸、比表面积的影响。用TG-DTG、BET、XRD、SEM、TEM等测试仪器对产物进行了表征。结果表明:温度的升高或煅烧时间的延长有助于提高氧化镁的结晶度,促进晶体生长,减小比表面积。在650℃下煅烧1 h可得到比表面积高达188.3 m^2/g的介孔网状氧化镁;在850℃下煅烧4 h,可得到棒状、哑铃状的MgO纳米颗粒。且将高比表面积介孔网状氧化镁经过再次“水化+煅烧”后可得到片状纳米氧化镁。Nanometer magnesia with different morphologies was prepared from natural hydromagnesite by controlling the calcination temperature and time under the simple process route of"calcination-hydration-calcination",and no reagent needed to be added in the experimental process.The effects of calcination temperature and time on the morphology,crystallinity,grain size,and specific surface area of magnesium oxide nanoparticles were studied.The product was characterized by TG-DTG,BET,XRD,SEM and TEM.The results showed that the increase of temperature or the extension of calcination time is helpful to improve the crystallinity of magnesium oxide,promote crystal growth and reduce specific surface area.Calcining at 650℃for 1h can obtain mesoporous reticular magnesium oxide with specific surface area as high as 188.3 m^2/g;After calcination at 850℃for 4 h,rod-shaped and dumbbell-shaped MgO nanoparticles can be obtained.And the high specific surface area mesoporous reticular magnesium oxide is hydrated and calcined again to obtain the flaky nano magnesium oxide.

关 键 词：水菱镁矿 煅烧 水化 高比表面积 形貌 纳米氧化镁 

分 类 号：TQ132.2[化学工程—无机化工]