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分别在 ６７３、 ８７３和 １０７３ Ｋ分解 Ｍｇ／Ａｌ摩尔比为 ３的水滑石生成 Ｍｇ（Ａｌ）Ｏ复合物。ＸＲＤ测定均显示 ＭｇＯ物相。８７３Ｋ以上焙烧的样品同时存在ＭｇＡｌ_２Ｏ_４尖晶石物相。微量吸附量热测定其表面酸碱中心的强度和密度，发现碱中心强度和密度顺序为：ＭＡＯ—２＞ＭＡＯ—３≈ＭＡＯ－１，而酸中心强度和密度顺序是：ＭＡＯ—１＞ＭＡＯ—３≈ＭＡＯ—２．红外光谱表明，Ｍｇ（Ａｌ）Ｏ复合物表面酸碱中心主要存在Ｌ酸，破中心是氧阴离子。焙烧温度对表面碱中心类型几乎没有影响。固态ＭＡＳ~(２７)Ａｌ核磁共振结果展示，这些样品呈现出显著的Ａｌ~(３＋)配位情况的变化．
Hydrotalcites with Mg / Al molar ratio of 3 were decomposed into Mg (Al) O complexes at 673, 873 and 1073 K, respectively. The XRD measurement shows the MgO phase. The sample calcined at more than 873K contains MgAl 2 O 4 spinel phase. The order of MAO-2> MAO-3≈MAO-1 and the order of acid center strength and density were MAO-1> MAO -3 ≈MAO-2. Infrared spectroscopy showed that there are mainly L acid in the acid-base center of the Mg (Al) O complex surface and oxygen anion in the broken center. The calcination temperature has almost no effect on the surface base type. Solid-state MAS ~ (27) Al nuclear magnetic resonance results show that these samples exhibit significant Al ~ (3+) coordination changes.