【摘要】 分别以甘氨酸、柠檬酸和丙烯酰胺辅助柠檬酸为络合试剂,采用溶胶凝胶燃烧法合成LaCoO₃复合氧化物,并对它们进行XRD、BET、SEM及O₂-TPD分析.实验结果表明,三种络合剂制备得到的产物均为纯钙钛矿LaCoO₃相;丙烯酰胺辅助柠檬酸溶胶凝胶燃烧法制得的LaCoO₃颗粒均匀且较小,比表面积最大,其O₂-TPD曲线中的峰面积最大,对苯完全催化氧化效果最好.更多还原

【Abstract】 LaCoO₃ perovskite- type mixed oxides were prepared by sol- gel combustion method. Glycine,citrate,and acrylamide assisted polymeric citrate were used as complexing agents,respectively.The catalysts were characterized by means of N₂ physical adsorption,X- ray diffraction（ XRD）,scanning electron microscopy（ SEM）,and temperature- programmed desorption of O₂（ O₂- TPD）.The catalytic result reveals that the LC- ACCA catalyst exhibited the highest activity for benzene total oxidation. The XRD result shows that single phase of LaCoO₃ perovskite was obtained by all of these three kinds of complexing agents. The LC- ACCA catalyst had uniform particles with relatively small sizes from SEM observation. Moreover,this catalyst exhibited higher lattice oxygen mobility,as indicated by O₂- TPD measurements. These properties are suggested to be responsible for the high activity in benzene total oxidation.更多还原