摘要
用X射线衍射、红外光谱、魔角旋转-核磁共振、扫描电镜以及盐酸浸取等手段研究了机械力化学效应对高岭石铝氧多面体的影响,并与高岭石的热活化进行了对比。结果表明,机械力化学效应使高岭石的铝氧八面体不断畸变,高岭石最终转变为长程无序的活性物质,这种物质同时存在AlIV、AlV和AlVI三种配位形式,AlVI的含量高于热转变产物偏高岭石。高岭石铝氧八面体中的羟基由于机械力化学效应逐渐脱除,产生的水分子部分以配位和氢键的连接方式存在于活性产物的结构中,其中配位水参与了Al的配位,产生了新的AlVI配位形式[AlO5(H2O)]。[AlO5(H2O)]中的AlVI和[AlO5]中的AlV具有相同的反应活性,高于偏高岭石中以[AlO6]形式存在的AlVI。
The influence of mechanochemical effect on Al-（O,OH） polyhedron of kaolinite was investigated using X-ray diffraction,infrared spectrum,magic-angle-spinning nuclear magnetic resonance,scanning electron microscope and hydrochloride acid leaching methods,compared with the thermal activation of kaolinite.The results showed that the Al-（O,OH） octahedron of kaolinite was distorted gradually due to the mechanochemical effect,giving rise to an active substance with long-range disorder,in the simultaneous presence of 4-,5-and 6-coordinated Al.The AlVI in this substance was more abundant than that in metakaolinite,which was obtained through thermal activation.The mechanochemical effect also led to the dehydroxylation of Al-（O,OH） octahedron of kaolinite,whereas part of the water involved in the structure of the active substance through coordination or hydrogen bond.The coordinated water was associated with Al,giving a new AlVI coordination of [AlO5（H2O）].The activity of the AlVI in [AlO5（H2O）] was the same as the AlV in ／,and higher than the AlVI of ／ in metakaolinite.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2011年第5期22-26,共5页
Journal of Wuhan University of Technology
基金
国家"863"计划(SQ2007AA06Z129028)
上海浦江人才计划(PJ200700339)
上海科学技术委员会重大专项(10dz1204901)
上海市重点学科建设项目(B506)
