制备方法及焙烧温度对Co_3O_4/CeO_2催化剂上CO低温氧化反应的影响  

Effect of Preparation Method and Calcination Temperature on Low-Temperature CO Oxidation over Co_3O_4/CeO_2 Catalyst

作　　者：邵建军[1] 张平[1] 唐幸福[2] 张保才[2] 宋巍[2] 徐奕德[2] 申文杰[2] 

机构地区：[1]装甲兵工程学院装备再制造国防科技重点实验室,北京100072 [2]中国科学院大连化学物理研究所催化基础国家重点实验室,辽宁大连116023

出　　处：《催化学报》2007年第2期163-169,共7页

摘　　要：分别采用沉淀氧化法、均匀沉淀法及络合燃烧法制备了Co3O4/CeO2复合氧化物催化剂,并在干燥及湿气条件下进行了CO氧化反应.结果表明,采用沉淀氧化法经538K焙烧制得的Co3O4/CeO2催化剂具有优异的CO低温氧化活性和较高的抗湿性能.在196K条件下,该催化剂上CO氧化的转化率为99%,并且可连续保持400min以上;当温度上升到298K时,经过2400min反应后,CO的转化率仍可达到94%;当反应气中含3.1%湿气,温度为383K时,经过2400min反应后,CO的转化率仍保持在79%.实验表明,Co3O4/CeO2催化剂的制备方法及焙烧温度对Co3O4与CeO2之间的相互作用有显著的影响,进而影响催化剂催化CO低温氧化的活性.Co3O4/CeO2 mixed oxides were prepared by coprecipitation-oxidation, homogeneous precipitation, and complexation-combustion methods. The catalysts were used to catalyze low-temperature CO oxidation under dry and humid conditions. The Co3O4/CeO2 catalyst prepared by the coprecipitation-oxidation method followed by calcination at 538 K exhibited excellent activity and good resistance to water vapor poisoning. Remarkably, a CO conversion of 99% was achieved at a temperature as low as 196 K and was maintained more than 400 min under the dry condition. When the reaction was carried out at 298 K, a CO conversion of 94% was obtained after running the reaction for 2 400 min. Even when 3.1 % steam was added, a CO conversion of 79% could be kept after 2 400 rain time-on-stream at 383 K. It is suggested that the strong interaction between Co3O4 and CeO2 is closely related to the preparation route and the calcination temperature and plays a crucial role in the CO oxidation over the Co3O4/CeO2 catalyst.

关 键 词：氧化钴 氧化铈 一氧化碳 

分 类 号：O643.36[理学—物理化学]