【摘要】 本文用镧、钡共同添加并使用溶胶-凝胶法制得改性氧化铝。详细研究了在保持 La含量为 5.2wt％时， Ba添加量的改变对氧化铝热稳定性的影响。实验结果表明镧、钡元素的共添加能大大增加氧化铝的热稳定性，从而使氧化铝在高温下保持高比表面积。体相中同时添加 5.2wt％ La和 2wt％ Ba以及 5.2wt％ La和 7wt％ Ba能使氧化铝保持较好的热稳定性，样品经 1100℃煅烧 20h后，比表面分别达 100.8m2· g-1和 92.3m2· g-1。通过对添加物与氧化铝保持高温高表面能力的内在联系的探讨，得出 Ba、 La元素的添加提高氧化铝热稳定性的原因主要表现在两方面：一是抑制氧化铝的微孔烧结速度；二是阻止了氧化铝向α相的转变。更多还原

【Abstract】 ： High surface area alumina resisting high temperature was prepared by sol-gel method.The effect of Barium on the thermal stability of alumina was studied when 5.2wt％ Lanthanum was added.The co-addition of Barium and Lanthanum can improve the surface area of alumina greatly.The modified alumina maintained surface area of 100.8m2· g-1, 92.3m2· g-1 respectively after calcination at 1100℃ for 20h when 5.2wt％ La and 2wt％ Ba or 5.2wt％ La and 7wt％ Ba were added, while the surface area of pure alumina was only about 10m2· g-1 after it was treated at the same conditions. BET, BJH and XRD were used to study the effect of addition of Barium and Lanthanum on the thermal stability of alumina. The results showed that the addition of Barium and Lanthanum can keep alumina from sintering and transition toα phase ,then suppress the decrease of surface area of alumina.更多还原