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用浸渍法制备了CeO2-ZrO2-La2O3复合氧化物,用XRD,TG-DTA,拉曼光谱、H2-TPR和BET表面积测定等方法对合成的样品进行了表征,研究了在单钯Pd/γ-Al2O3催化剂中添加CeO2-ZrO2-La2O3对催化剂活性和热稳定性的影响。结果表明,在Pd/γ-Al2O3中加入三元复合氧化物有利于提高三效催化剂的热稳定性,有利于阻止γ-Al2O3在高温时的相变以稳定Al2O3结构,防止在高温条件下催化剂表面积的损失。在Pd的负载量为1 g·L-1条件下,测定了Pd/CeO2-ZrO2-La2O3/γ-Al2O3/蜂窝陶瓷催化剂对CO,C3H6和NO净化的三效活性,研究了催化剂的结构和三效催化活性之间的关系。结果表明,CeO2-ZrO2-La2O3的存在能明显提高Pd基催化剂对CO,C3H6和NO的三效净化活性,扩大催化剂的操作窗口,提高在富氧条件下对NOx的还原性能。
The CeO2-ZrO2-La2O3 composite oxides were prepared by impregnation method. The synthesized samples were characterized by XRD, TG-DTA, Raman spectroscopy, H2-TPR and BET surface area measurement. Effect of CeO2-ZrO2-La2O3 on the Activity and Thermal Stability of Al-Al2O3 Catalyst. The results show that the addition of ternary complex oxide to Pd / γ-Al2O3 can improve the thermal stability of the three-way catalyst, prevent the phase transition of γ-Al2O3 at high temperature to stabilize the structure of Al2O3 and prevent the catalyst Loss of surface area. The three-way activity of Pd / CeO2-ZrO2-La2O3 / γ-Al2O3 / honeycomb ceramic catalysts for the purification of CO, C3H6 and NO was measured under the Pd loading of 1 g · L-1. The structure and The relationship between the three-way catalytic activity. The results show that the presence of CeO2-ZrO2-La2O3 can significantly improve the three-way catalytic activity of Pd-based catalysts for CO, C3H6 and NO, enlarge the operating window of the catalyst and improve the NOx reduction performance under oxygen-rich conditions.