摘要
以氯化镁为原料、水为介质、尿素[CO(NH2)2]为沉淀剂、柠檬酸钠为添加剂,采用水热法一步合成出无水碳酸镁粉体。利用X射线衍射、扫描电子显微镜、热重–差示扫描量热仪研究了添加剂、水热温度和时间对产物相结构和微观形貌的影响,并对影响机理进行了分析。结果表明:在无添加剂条件下,反应生成的初始产物为板状Mg5(CO3)4(OH)2·4H2O粉体,提高温度并延长水热处理时间,产物转变为无水碳酸镁;在有柠檬酸钠添加剂条件下,反应生成的初始产物为中空球形Mg3O(CO3)2相,随水热温度提高和水热时间延长,Mg3O(CO3)2向无水碳酸镁转变,同时其微观形貌也由中空球形向片组装的花型结构转变。
Anhydrous magnesium carbonate powder was synthesized by a hydrothermal method using magnesium chloride as raw materials, urea as a precipitation agent and sodium citrate as a surfactant. The effect of hydrothermal condition on the microstructure of the obtained powder was investigated by scanning electron microscopy, X-ray diffraction and thermogravimetric–differential scanning calorimetry, respectively. The results show that the primary product is a plate-like powder of Mg5(CO3)4(OH)2·4H2O without any additives. Anhydrous magnesium carbonate powder can be obtained when the temperature and time are increased. The primary product was a hollow sphere-like powder when using sodium citrate as additives. Mg3O(CO3)2 transforms into anhydrous magnesium carbonate when the hydrothermal temperature and time increase. The micro-morphology of the product also changes from a hollow spherical structure to a flower-like structure assembled by slices.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2015年第3期327-333,共7页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(51274052)资助项目
关键词
碳酸镁
水热法
柠檬酸钠
magnesium carbonate
hydrothermal method
sodium citrate
