CeZrYLaO对Fe基整体式稀薄甲烷催化燃烧性能的影响

采用共沉淀法制备了高性能低铈储氧材料Ce_0.35Zr_0.55Y_0.07La_0.03O_1.95(OSM，储氧材料)和胶溶法制备了耐高温、高比表面的La-Al₂O₃并以它们为载体，制备了一系列整体式铁基催化剂。考察了该系列催化剂对甲烷稀薄燃烧的催化性能，并用低温N₂吸附-脱附，储氧能力(oxygen storage capacity，OSC)，XRD，XPS和H₂-TPR等测试手段对载体和催化剂进行了表征。活性测试结果表明所制得的整体式催化剂Fe/OSM+La-Al₂O₃可在50 000 h^-1的高空速条件下使含量为1%的甲烷在474 ℃起燃，565 ℃完全转化；低温氮吸附-脱附测试结果表明，所制得的Ce_0.35Zr_0.55Y_0.07La_0.03O_1.95经1 050 ℃焙烧5 h后的BET比表面积达33 m²·g^-1，孔容为0.14 mL·g^-1；La-Al₂O₃经1 050 ℃焙烧5 h后的BET比表面积达125 m²·g^-1，孔容为0.46 mL·g^-1，是优良的催化剂载体；OSC测试结果表明，加入储氧材料(oxygen storage material(OSM))能增加催化剂的储氧性能，有利于催化活性的提高；XRD测试结果表明，OSM以均一固溶体存在；XPS测试结果表明，Fe₂O₃与OSM载体之间的相互作用最强；H₂-TPR测试结果表明，加入OSM能增加催化剂的还原性能，从而提高了催化活性。

Influence of CeZrYLaO Solid Solution on Performance of Fe2O3-Based Monolith Catalyst for Catalytic Combustion of Methane

Ce_(0.35)Zr_(0.55)Y_(0.07)La_(0.03)O_(1.95) (OSM) (OSM =oxygen storage material), La-Al_2O_3 were prepared by coprecipitation and peptizing method, respectively. Monolith catalysts of Fe_2O_3 supported on prepared material were obtained by impregnation method and the catalytic activity for methane combustion under low concentration was investigated. The results of activity test show that methane starts to convert at 474 ℃ and convert completely at 565 ℃ on the monolith catalyst Fe/OSM +La-Al_2O_3 under gas hourly space velocity (GHSV) 50 000 h~(-1). The catalysts were characterized by low temperature nitrogen adsorption-desorption, oxygen storage capacity (OSC), X-ray diffraction (XRD), XPS and H_2-temperature-programmed reduction(H_2-TPR) methods. The low temperature nitrogen adsorption-desorption results show that the oxygen-storage materials calcined at 1 050 ℃ for 5 h could maintain higher specific surface area(33 m~2·g~(-1)) and larger pore volume(0.13 mL·g~(-1)) and the BET specific surface area and BJH pore volume for La-Al_2O_3 were 125 m~2·g~(-1) and 0.46 mL·g~(-1), respectively. The results of OSC indicate that OSC is improved through the incorporation of OSM. The results of XRD reveal that OSM exists in uniform solid solution. The results of XPS reveal that the interaction between Fe_2O_3 and OSM support was the strongest. The results of H_2-TPR indicate the incorporation of OSM enhances the reduction properties of the catalysts thus improving the catalytic activity.