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以硅改性的氧化铝为载体,用反相微乳液法合成了负载型的CeO2-ZrO2固溶体(Ce-Zr-O/Si-Al2O3),用低温氮吸附、X射线衍射、程序升温还原、拉曼光谱和X射线光电子能谱等方法对Ce-Zr-O/Si-Al2O3的织构性能、热稳定性和储放氧性能等进行了表征.结果表明,负载后的CeO2-ZrO2晶相与负载前相比没有变化,但热稳定性和在低温下的放氧能力及总储氧量明显提高.作为甲烷燃烧Pd催化剂的载体,Ce-Zr-O/Si-Al2O3的性能明显优于CeO2-ZrO2,Si-Al2O3和机械混合物CeO2-ZrO2+Si-Al2O3.使用0.2%Pd/10%Ce-Zr-O/Si-Al2O3为催化剂时,甲烷90%转化率时的温度仅为345℃,比负载在其它载体上的Pd催化剂低175℃.
The Ce-Zr-O / Si-Al2O3 solid solution (Ce-Zr-O / Si-Al2O3) was synthesized by inverse microemulsion method using silicon modified alumina as carrier. The solid solution was characterized by low temperature nitrogen adsorption, X-ray diffraction, temperature programmed reduction, Raman spectroscopy and X-ray photoelectron spectroscopy were used to characterize the texture properties, thermal stability and oxygen evolution performance of Ce-Zr-O / Si-Al2O3.The results show that the crystalline structure of CeO2-ZrO2 There was no change compared with that before loading, but the thermal stability and oxygen evolution ability at low temperature and the total oxygen storage capacity increased obviously.As a carrier of methane combustion Pd catalyst, the performance of Ce-Zr-O / Si-Al2O3 was obviously better than CeO 2 -ZrO 2, Si-Al 2 O 3 and CeO 2 -ZrO 2 + Si-Al 2 O 3 were used as the catalyst.When 0.2% Pd / 10% Ce-Zr-O / Si-Al 2 O 3 was used as the catalyst, the conversion of methane at 90% , 175 ° C lower than the Pd catalyst supported on other supports.