摘要
利用Keggin结构可以发生类质同象置换的性质,制备了含过渡金属离子Fe的聚羟基铁铝复合柱撑蒙脱石。运用紫外-可见吸收光谱、^(27)Al核磁共振谱等技术对复合柱撑溶液中的Fe和Al的状态进行了研究。运用X射线定向衍射技术、红外光谱、顺磁共振等技术对复合柱撑粘土中Keggin结构的作用及热稳定性进行了研究。结果表明:Fe/Al摩尔比对聚羟基铁铝柱撑液的结构、d(001)值、复合柱撑粘土的热稳定性均有较大的影响,随着Fe/Al摩尔比的增加,d(001)逐渐增大,热稳定性下降,过量的Fe对Keggin结构有破坏作用,Keggin结构的存在增加了复合柱撑粘土的热稳定性。
The pillared montmorillonite containing Fe3+ ion was prepared by substituting Fe3+ for Al3+ in Keggin ions with Keg-gin structure. 27Al NMR and UV spectroscopy were used to monitor the environment of Fe3+ and A13+ in solution. The thermal stability of pillared clays was determined by XRD, IR, EPR. The results show that the structure of hydroxy - Fe - Al oli-gomer, d(001) values and the thermal stability of pillared clay are affected by the molar ratio of Fe/Al in pillared solution. The d(001) values increase and the thermal stability decrease with the increasing of Fe/Al molar ratio. Excessive amounts of Fe3+ i-ons can destroy the Keggin structure. The existence of Keggin structure can improve the thermal stability of the pillared clays.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2003年第10期1016-1020,共5页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(40202007)
广东省自然科学基金(000623
020938)
关键词
聚羟基铁铝
复合柱撑蒙脱石
KEGGIN结构
稳定性
polyhydroxy - iron - aluminium
hybrid pillared montmorillonite
Keggin structure
stability
