摘要
用XRD、SEM及热重技术分析了共沉淀法、水热法、水合再生法制备水滑石的理化性质,结果显示水热法所得产品结晶度高,一次结晶粒径大,且表面规整度高,热稳定性好;而共沉淀法易造成结晶团聚,粒径分布范围大.根据水滑石的记忆功能发展而来的水合再生法,可以实现水滑石层间不同阴离子交换,表现出“智能”化的特性.
Mg-Al hydrotalcites were synthesised by coprecipitation, hydrothermal and hydro-reconstruction methods. Detailed comparative analysis of structure and morphology were made by XRD, SEM and TG-DSC techniques. It had been found that the hydrothermal treatment elevated the hydrotalcite content and significantly improved the hydrotalcite crystallinity. Meanwhile a growth of hydrotalcite crystals and a remarkable decrease of surface area were observed after hydrothermal treatment. Since a strong agglomeration of primary particles occurred during preparation, the particle size of the samples synthesized by coprecipitation distributes in a wide range. Governed by a strong edge-surface platelet interaction, these aggregates gathered in a form so-called ＂sand rose morphology＂. XRD patterns and scanning electron micrographs revealed that rehydration of the samples calcined at 450℃ resuked in the reconstruction of the layered structure,owing to its ＂memory effect＂.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2006年第5期673-676,共4页
Journal of Xiamen University：Natural Science
基金
国家自然科学基金(20203014)资助
关键词
水滑石
水热法
水合再生
hydrotalcite
hydrothermal
rehydration
