摘要
合成了一系列具有不同Mn/Ce掺杂比例的Cu基整体式催化剂,并使用其进行了稀薄甲烷催化燃烧活性测试。其中,4Cu-3Mn-1Ce催化剂展现出最佳的甲烷催化活性,在550℃下转化率达85.0%,并且在600℃下实现了完全转化。利用包括原位红外光谱(in situ FTIR)在内的一系列表征分析与密度泛函理论(DFT)模拟计算探究了Mn/Ce掺杂对Cu基整体式催化剂理化性质的作用机制,Mn/Ce掺杂强化Cu基整体式催化剂稀薄甲烷催化燃烧活性可以归因为:Ce掺杂构建Ce-Cu固溶体,弱化Cu—O键合,促进高温下晶格氧的扩散,从而强化高温催化活性;Mn掺杂促进催化剂对O_(2)的吸附,强化低温下甲烷的催化活性;Mn/Ce共掺杂强化O_(2)活化并解离为*O,*O填补进入氧空位再生为晶格氧,共掺杂强化了氧物种循环,从而显著提高稀薄甲烷催化燃烧活性。
In this study,a series of Cu-based monolithic catalysts with different Mn/Ce doping ratios were synthesized and used for catalytic combustion activity testing of dilute methane.Among them,the 4Cu-3Mn-1Ce catalyst exhibited the best methane catalytic activity with a conversion of 85.0%at 550℃and achieved complete conversion at 600℃.The mechanism of the effect of Mn/Ce doping on the physicochemical properties of Cu-based monolithic catalysts was investigated by characterization analysis,including in situ Fourier Transform infrared spectroscopy(in situ FTIR),and density functional theory(DFT)simulation calculations.The enhanced methane catalytic combustion activity of the Cu-based monolithic catalysts can be attributed to the following:Ce doping forming a Ce-Cu solid solution,weakening the Cu—O bond,and promoting lattice oxygen diffusion at high temperatures,thus enhancing high-temperature catalytic activity;and Mn doping promotes the adsorption of O_(2)on the catalysts,which strengthens methane oxidation at low temperatures;Mn/Ce co-doping strengthens the activation of O_(2)and its dissociation to*O,which fills the oxygen vacancies and regenerates into lattice oxygen,the co-doping strengthens the cycle of oxygen species and thus significantly improves the catalytic combustion activity of thin and dilute methane.
作者
邱家齐
杨仲卿
张志刚
甘海龙
霍春秀
窦志帅
冉景煜
QIU Jiaqi;YANG Zhongqing;ZHANG Zhigang;GAN Hailong;HUO Chunxiu;DOU Zhishuai;RAN Jingyu(Key Laboratory of Low-grade Energy Utilization Technologies and Systems,Ministry of Education,Chongqing University,Chongqing 400044,China;School of Energy and Power Engineering,Chongqing University,Chongqing 400044,China;China Coal Technology and Engineering Group Chongqing Research Institute,Chongqing 400039,China)
出处
《化工学报》
北大核心
2025年第11期5604-5616,共13页
CIESC Journal
基金
国家自然科学基金项目(52276099)
中煤科工集团科技计划项目(2024-TD-ZD020)
中煤科工集团重庆研究院有限公司自立项目(2024ZDYF19)。
关键词
催化
甲烷
活化
燃烧
掺杂
catalysis
methane
activation
combustion
doping
