摘要
根据对我国八个不同成因和特征的高岭土样品在450～1450℃热处理产物的MASNMR谱和XRD、IR、DTA等研究结果，结合有关资料讨论了高岭石-莫来石反应序列的几个重要问题：①变高岭石的结构，尤其是五配位铝；②980℃放热峰后的高温相是γ－AlO3而不是Al－Si尖晶石;③对于莫来石化过程，认为初始莫来石在850～950℃变高岭石形成，二次莫来石由分凝的SiO2T和γ－Al2O3在1200～1300℃反应形成。
Based on the MAS NMR, XRD, IR and DTA data 'of eight kaolinite samples andtheirthermal transformation products during 450～1 450℃,which have different geological genesesand characteristics, some important problems of kaolinite-mullite reaction series are discussed inthis paper.(1)Metakaolinite structure,especially 5-coordination aluminum.(2)The high-temperature phase related with the exothermal peak near 980℃ should be γ-Al2O3 rather than Al-Si spinel.(3)In the course of mullite formation,primary mullite is formed from metakaolinite at 850～950℃,the secondary mullite is formed through the reaction between segregated SiO2 and γ-Al2O3 at1 200～1 300℃.
出处
《矿物学报》
CAS
CSCD
北大核心
1997年第3期250-259,共10页
Acta Mineralogica Sinica
基金
国家自然科学基金!49272085
关键词
高岭石
变高岭石
莫来石
核磁共振谱
铝27
硅29
kaolinite
metakaolinite
mullite
magic-angle-spinning nuclear magnetic resonance (MAS NMR)spectrum
