摘要
以天然高岭土为原料,联合氧化-还原工艺和黄铁矾法去除有机质和杂质,采用常压、开放水热晶化法制得了主晶相为莫来石的复相纳米晶。实验利用XRD、SEM对在不同条件下制得样品的晶相组成、形貌进行了表征。研究结果表明:前驱体精矿粉(一次莫来石、二次莫来石)的选择是影响主晶相为莫来石复相纳米晶水热合成的主要原因之一;在煅烧温度为1170℃、水热晶化温度为75℃、NaOH浓度为3mol/L、晶化时间为5h时,制得的纳米粉体含有莫来石和二氧化硅,颗粒形貌为类球形,少部分呈针状,颗粒平均粒径约为100nm。
The mullite nanocomposite was synthesized through an open-system hydrothermalcrystallization method under normal pressure from raw natural kaolin, which is first processed by both oxidation-reduction fining method and conventional jarosite techniques to remove impurities. The crystal phase and microstructure of samples prepared under different preparation conditions were investigated and compared to using X-ray diffraction （XRD） and scanning electron microscope （SEMi, rcspetively. The results show that selecting proper fine powders calcined at different temperatures （e.g. primary mullite and secondary mullite） benefits the formation of mullite nanocomposite ：when sintered temperature 1170℃, hydrothermal reaction temperature 85℃. NaOH concentration 3mol/L. hydrothermal reaction time 5h, there exists mullite and SiO2 in the prepared nanopowder with the average grain sizes of 100 nm, and the morphology of the nanocomposite appears spherical-like, also some needle-like shape can be found, too.
出处
《非金属矿》
CAS
CSCD
北大核心
2008年第5期12-13,16,共3页
Non-Metallic Mines
基金
广西自然科学基金(0542012)
广西科技攻关项目(桂科能05112001)
广西研究生教育新人才基地项目
关键词
莫来石
水热法
高岭土
纳米粉体
mullite hydrothermal method natural kaolin nanopowder
