Abstract

An Mg-Al layered double hydroxides (LDHs) intercalated by glutamate ions (Glu/LDH) was obtained using co-precipitation processing. The influence of stirring and aging time on LDH morphology was investigated. The morphology of LDH was characterized by means of XRD, FT-IR, FE-SEM and XPS. The thermal stability, pore volume and specific surface area were probed through thermal gravimetric (TG) analysis and automatic specific surface area analyzer, respectively. The results showed that the stirring and aging time had an insignificant influence on the interlayer distance of Glu/LDH; while it had a critical impact on the crystallinity degree of the Glu/LDH structure. TG analysis designated that the thermal stability of glutamate ion intercalated in LDH layers was higher than that of glutamate ion before intercalation. Glu/LDH exhibited the best adsorption performance at a stirring and aging time of 12 h. A schematic molecular structure model of Glu/LDH was proposed.

摘要

使用共沉淀处理获得了由谷氨酸离子 (Glu/LDH) 插入的 Mg-Al 层状双氢氧化物 (LDH)。研究了搅拌和老化时间对LDH形态的影响。LDH的形貌通过XRD、FT-IR、FE-SEM和XPS表征。分别通过热重（TG）分析和自动比表面积分析仪探测热稳定性、孔体积和比表面积。结果表明，搅拌和老化时间对Glu/LDH的层间距影响不显着；而它对 Glu/LDH 结构的结晶度有重要影响。TG分析表明，嵌入LDH层的谷氨酸离子的热稳定性高于嵌入前谷氨酸离子的热稳定性。Glu/LDH 在搅拌和老化时间为 12 h 时表现出最好的吸附性能。提出了Glu/LDH的分子结构示意图。