Pd/CeO_(2)上乙酸丁酯高效深度氧化性能与机理研究  

Study on the performance and mechanism of high-efficiency deepoxidation of butyl acetate over Pd/CeO_(2)

作　　者：孔文晶 林佳佳 钟雪芸 邢赟 刘鹏 李振国[3] 付名利 KONG Wenjing;LIN Jiajia;ZHONG Xueyun;XING Yun;LIU Peng;LI Zhenguo;FU Mingli(College of Environment and Energy,South China University of Technology,Guangzhou 510006,China;Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control,Guangzhou 510006,China;National Engineering Laboratory for Mobile Source Emission Control Technology,China Automotive Technology&Research Center Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]华南理工大学环境与能源学院,广东广州510006 [2]广东省大气环境与污染控制重点实验室,广东广州510006 [3]中国汽车技术研究中心有限公司移动源排放控制技术国家工程实验室,天津300300

出　　处：《能源环境保护》2024年第4期198-208,共11页Energy Environmental Protection

基　　金：国家移动源排放控制技术工程实验室(NELMS2020A06);国家自然科学基金面上资助项目(51878293)。

摘　　要：新能源汽车和相关领域中,对于典型含氧挥发性有机物乙酸丁酯的治理越来越重要。通过引入0.5%的Pd来调节CeO_(2)-U催化剂的表面结构和理化性质,并与含等量Pd的Al_(2)O_(3)和TiO_(2)进行对比,通过SEM、XPS、in-situ DRIFTS等手段对催化剂进行表征,以探究Pd和Ce活性组分间的协同作用对乙酸丁酯(BA)催化氧化性能的影响。研究结果表明,在220℃下引入Pd使CeO_(2)-U的CO_(2)产率由77.8%提高至90.7%,明显促进了BA的深度氧化进程,缓解了CO_(2)选择性滞后的问题。Pd的引入改善了CeO_(2)中晶格氧的移动性和反应性,增加了表面Ce^(3+)的含量,提高了表面氧空位浓度。结合in-situ DRIFTS图谱分析,证实了Pd/CeO_(2)-U上BA的催化氧化机理,即在低温段(T<200℃)遵循Langmuir-Hinshelwood(L-H)机理,在高温段(T>200℃)遵循Mars-van Krevelen(MvK)反应机理,并且发现中间产物羧酸盐的分解为关键的控速步骤。本研究结果可为相关领域乙酸丁酯的治理提供借鉴。In the field of new energy vehicles and related sectors,treating butyl acetate(BA),a typical oxygen-containing volatile organic compound(VOC),is becoming increasingly important.The surface structure and physicochemical properties of a CeO_(2)-U catalyst were adjusted by introducing 0.5%Pd,and compared with Al_(2)O_(3)and TiO_(2)catalysts containing the same Pd loading.Characterizations using SEM,XPS,in-situ DRIFTS,and other methods were conducted to explore the synergistic effect of Pd and Ce active components on catalytic oxidation of BA.The results showed that the introduction of Pd increased CeO_(2)-U′s CO_(2)yield from 77.8%to 90.7%at 220℃,significantly promoting the deep oxidation process of BA and alleviating the issue of CO_(2)selectivity delay.The introduction of Pd enhanced the mobility and reactivity of lattice oxygen in CeO_(2),increased the proportion of surface Ce^(3+),and boosted surface oxygen vacancy concentration.Additionally,the catalytic oxidation mechanism of BA over Pd/CeO_(2)-U was confirmed through in-situ DRIFTS analysis,indicating that the L-H mechanism was followed at low temperatures(T<200℃),while the MvK reaction mechanism occurred followed at high temperatures(T>200℃).It was found that the decomposition of intermediate carbox-ylate served as the rate-controlling step.These findings have implications for controlling BA in the field of related sectors.

关 键 词：乙酸丁酯 Pd/CeO_(2) 催化氧化 CO_(2)选择性 氧空位 

分 类 号：X701[环境科学与工程—环境工程]