【摘要】 采用溶胶低温燃烧法制备了单一组成的La0.3Sr0.7Fe0.7Cu0.2Mo0.1O3-δ(LSFCM)超细钙钛矿陶瓷粉体。用XRD,SEM以及TA等方法对粉体的物相、形貌、粒度以及导电性能等进行了表征。考察了LSFCM陶瓷粉体对甲烷部分氧化(POM)制备合成气的催化活性与稳定性。结果表明:溶胶燃烧粉末经800℃下煅烧4h可得到平均粒径小于35nm的立方钙钛矿结构LSFCM陶瓷粉体,相对密度为96.7%的LSFCM烧结体在空气气氛600℃温度下电导率达到26.27S·cm-1,在950℃、CH4/O2比为1.5~2.0时,甲烷转化率及一氧化碳与氢气选择性均达到90.0%以上;反应43h后虽产生少量积炭,但仍能保持钙钛矿结构,表明LSFCM粉体对甲烷部分氧化制合成气反应具有良好的催化活性和稳定性。更多还原

【Abstract】 La0.3Sr0.7Fe0.7Cu0.2Mo0.1O3-δ(LSFCM)ultrafine perovskite powder with homogeneous composition was synthesized via sol-gel low temperature combustion process.The phase,morphology,particle size and electrical conductivity of samples were characterized by XRD,SEM and TA measurements.The effect of LSFCM powder on the catalytic activity and stability in the partial oxidation of methane(POM)into syngas was investigated.The results indicate that LSFCM ceramic powders with cubic perovskite structure and the mean particle size of less than 35 nm can be obtained by calcinations of sol-gel combustion ash at 800℃for 4h.The conductivity of the LSFCM oxide measured on a sintered body having the relative density of 96.7%reaches up to 26.27S·cm-1 at 600 ℃in air atmosphere.The LSFCM powders exhibit excellent catalytic activity and good stability to the partial oxidation of methane into syngas.The methane conversion and CO and H2 selectivities reach above 90%in the CH4/O2 feed ratio of 1.5-2.0at 950 ℃.XRD and TA analysis reveal that the LSFCM powders still maintain the perovskite structure with a slight coke deposition after 43 hof reaction.更多还原