Ce0.5+xZr0.4-xLa0.1O2-Al2O3催化剂催化燃烧柴油车碳烟

采用共沉淀法制备了系列Ce_0.5+xZr_0.4-xLa_0.1O₂-Al₂O₃催化剂, 其中0≤x≤0.4且Ce_0.5+xZr_0.4-xLa_0.1O₂与Al₂O₃的质量比为1:1. 考察了该系列催化剂对柴油车排放碳烟的催化燃烧性能, 并用低温N2吸附-脱附、X射线衍射(XRD)、X射线光电子能谱(XPS)、氢气程序升温还原(H₂-TPR)和氧气程序升温脱附(O₂-TPD)等手段对催化剂进行了表征. 研究结果表明该系列催化剂均形成了具有立方萤石结构的固溶体. 当x=0.2时, Ce³⁺离子在催化剂表面有一定的富集, 此时催化剂具有最大的β氧脱附峰和最好的表面还原性能, 同时具有良好的催化碳烟氧化活性, 碳烟在该催化剂的起燃温度为360 °C, 具有较好的应用前景.

Catalytic Combustion of Diesel Soot over Ce_(0.5+x)Zr_(0.4-x)La_(0.1)O_2-Al_2O_3 Catalysts

Ce0.5+x Zr0.4-x La0.1O2-Al2O3 catalysts were prepared by co-precipitation, where 0≤x≤0.4 and the mass ratio of Ce0.5+xZr0.4-xLa0.1O2:Al2O3 was 1:1. The catalytic activities of these catalysts for the catalytic combustion of diesel soot were investigated. The catalysts were further characterized by low temperature nitrogen adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2- temperature-programmed reduction (H2-TPR), and O2-temperature-programmed desorption (O2-TPD). The results showed that all the catalysts formed solid solutions with a fluorite-like structure. When x=0.2, the Ce3+ ions were partly rich on the surface of the catalyst. The catalyst was easily reduced by H2 and the desorption peak area of the β oxygen species was the largest. The light-off temperature was 360 °C for the catalytic combustion of diesel soot over the catalyst suggesting good catalytic activity and potential application in diesel soot catalytic combustion.