离子交换蒙脱石的热稳定性

THERMAL STABILITY ON ION-EXCHANGED MONTMORILLONITE

从天然膨润土出发,制备了Ni^(2+)蒙脱石(简表成Ni_(2+)-M)催化剂,并在液相脱硫过程中评价了它们的催化氧化活性.样品的DTA与TPR结果表明,蒙脱石层间可交换Ni^(2+)离子在较高温度下可以直接与氧结合成氧化物,对于Ni^(2+)-M催化剂高温失活,这种结合的影响可能较Ni^(2+)离子受热激活而嵌入层结构的影响更为重要。

The Ni montmorillonite catalyst is prepared from raw bentonite and its activityof catalytic oxidation is evaluated in the desulfuration from liquid phase. The deter-mined and analysed results of DTA and TPR show that the exchangeable Ni-ionsbetween the sheets of the montmorillonite can immediately combine with oxygen toform oxides under higher temperature. The effect of the oxidation on the drop ofthe catalytic activity of Ni montmorillonite is probably more important than that ofthe Ni-ions embed in the sheet structure due to heat-activation.