摘要
采用溶胶-凝胶法制备了B位Fe和Co共取代的LaMn1-x-yFexCoyO3-δ钙钛矿型复合氧化物,并用于化学链甲烷部分氧化制合成气。X射线衍射(XRD)结果表明Fe和Co均进入了LaMnO3的晶格形成钙钛矿晶相,活性和稳定性测试表明LaMn1/3Fe1/3Co1/3O3-δ载氧体具有最佳的化学链甲烷部分氧化性能。CH4程序升温还原(CH4-TPR)表征发现LaMn1/3Fe1/3Co1/3O3-δ具有比LaBO3(B=Co,Mn,Fe)更高的甲烷活化能力和晶格氧迁移性能。甲烷恒温脉冲反应(CH4-pulsereaction)进一步证实了B位离子的协同作用可以提高LaBO3(B=Co,Mn,Fe)的表面反应速率。程序升温氢气还原(H2-TPR)表明,LaMn1/3Fe1/3Co1/3O3-δ中晶格氧具有适中的氧化还原能力,适合用于化学链甲烷部分氧化。
LaMn1-x-yFexCoyO3-δperovskite-type composite oxides co-substituted with B-site Fe and Co were prepared by the sol-gel method,and used for the chemical looping partial oxidation of methane to syngas.The XRD results suggest that Fe and Co were incorporated into the lattice of LaMnO3 and formed perovskite phase.Reactivity and stability tests show that LaMn1/3Fe1/3Co1/3O3-δoxygen carrier has the best reaction performance.CH4-TPR results indicate that LaMn1/3Fe1/3Co1/3O3-δhas higher methane activation and lattice oxygen migration rates than those of LaBO3(B=Co,Mn,Fe).CH4-pulse reaction further confirms that the synergistic effect of B-site ion substitution can improve the surface reaction rate of LaBO3(B=Co,Mn,Fe).H2-TPR results show that the lattice oxygen in LaMn1/3Fe1/3Co1/3O3-δhas moderate redox capacity,which is suitable for partial oxidation of methane.
作者
苏迎辉
郑浩
张磊
曾亮
SU Yinghui;ZHENG Hao;ZHANG Lei;ZENG Liang(Key Laboratory for Green Chemical Technology of Ministry of Education,School of Chemical Engineering and Technology,Tianjin University,Tianjin 300072,China;Foshan(Southern China)Institute for New Materials,Foshan 528000,Guangdong,China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2020年第11期5265-5277,共13页
CIESC Journal
基金
国家重点研发计划项目(2018YFB0605405)
国家自然科学基金项目(U1663224)
多相复杂系统国家重点实验室开放基金项目(MPCS2019D05)。
关键词
部分氧化
化学链
甲烷
钙钛矿
合成气
载氧体
partial oxidation
chemical looping
methane
perovskite
syngas
oxygen carrier
