Ce_xMn_(10-x)O_(20-δ)固溶体氧化物的甲烷催化燃烧性能研究  

Methane Catalytic Combustion on CexMn_(10-x)O_(20-δ) Solid Solution Oxides

作　　者：侯红霞[1] 蒋政[2] 苏继新[3] 温美娟[1] 

机构地区：[1]北京科技大学应用学院,北京100083 [2]中科院生态环境研究中心,北京100085 [3]山东大学环境科学与工程学院,济南250100

出　　处：《精细石油化工进展》2004年第12期1-6,共6页Advances in Fine Petrochemicals

基　　金：国家863计划项目支持山东省优秀中青年科学家科研奖励基金(02BS060)山东大学青年教师基金资助课题。

摘　　要：　采用共沉淀法制备了系列CexMn10-xO20-δ固溶体氧化物甲烷燃烧催化剂,并采用XRD和BET对所得催化剂进行了表征。结果表明,在适当的Ce/Mn摩尔比范围内,试样经500℃焙烧可形成Ce/Mn固溶体复合氧化物,更高焙烧温度则导致催化剂比表面积下降和一定程度的烧结。500℃和800℃焙烧催化剂的活性变化规律略有不同,其活性主要由Ce/Mn摩尔比决定,其中活性最高的催化剂中Ce/Mn摩尔比为7:3。100 h稳定性试验结果表明,经800℃焙烧的Ce3Mn7O20-δ催化剂具有良好的热稳定性。典型催化剂在低转化率下的宏观动力学实验结果表明, 甲烷催化燃烧在CexMn10-xO20-δ固溶体氧化物催化剂上为一级动力学反应,反应速率受催化剂固有性质控制。A series of CexMn10-xO20-δ oxides catalysts was prepared by co - precipitation methods, and the obtained materials were characterized by XRD and BET specific surface areas ( SSA). The results showed that the CexMn10-xO20-δ oxides formed after calcination at 500℃, and calcination at higher temperatures (typically 800℃) resulted in surface areas decreasing and partial sintering. The activities of methane catalytic combustion varied regularly with Mn dopants, and dominantly depended on the Ce/Mn molar ratio. The optimum catalyst was Ce3Mn7O20-δ.No deactivation appeared for typical Ce3Mn7 oxides during reactions at 600℃ for 100 h. Kinetic analysis indicated that CexMn10-xO20-δ solid solution oxide catalysts for methane catalytic combustion were first order reactions, and reaction rate was controlled by intrinsic properties of catalyst surfaces.

关 键 词：氧化物催化剂 摩尔比 固溶体 甲烷催化燃烧 复合氧化物 宏观动力学 性能研究 甲烷燃烧 BET 反应速率 

分 类 号：O643.3[理学—物理化学]