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运用表面积测定，孔径分布，晶相检测等仪器分析方法对作为催化剂载体的多孔ＳｉＯ２的烧结行为进行了考察．发现非晶ＳｉＯ２微细颗粒在６００℃～７００℃间即开始烧结；在恒定温度下，烧结过程并非匀速，而是分成不同的快速烧结阶段．烧结后比表面积减小，但平均孔径增大．加入碱土金属氢化物ＭＯ后，原ＳｉＯ２的表面积减小，烧结后表面积的损失更大；相比而言，加入ＭｇＯ对比表面积影响较小，而加入ＢａＯ则影响较大．对第一快速烧结阶段建立了速率方程；运用分型几何模型理论较好地解释了不同快速烧结阶段问题以及与之相应的不同半径微孔收缩封堵的关系．对于烧结过程中的伴随现象亦进行了探讨．
The sintering behavior of porous SiO2 as a catalyst carrier was investigated by surface analysis, pore size distribution and crystal phase analysis. It is found that the amorphous SiO2 fine particles begin to sinter at 600 ℃ ~ 700 ℃. At constant temperature, the sintering process is not uniform, but divided into different rapid sintering stages. After sintering, the specific surface area decreases but the average pore size increases. After the addition of alkaline earth metal hydride MO, the surface area of the original SiO2 decreases and the loss of surface area after sintering is larger. In contrast, the addition of MgO has little effect on the specific surface area, while the addition of BaO has a greater impact. The rate equation was established for the first rapid sintering stage. The application of the sub-type geometric model theory explained the relationship between the different rapid sintering stages and the corresponding shrinkage closure of micropores with different radii. The concomitant phenomenon in the sintering process is also discussed.