CeO_2-MnO_x催化剂形貌对低浓度甲烷催化燃烧反应性能的影响  

Morphological effect of CeO_2-MnO_x catalyst on their catalytic performance in lean methane combustion

作　　者：李树娜[1] 宋佩 张金丽 贺小霞 解一昕 张亚刚[2] 王瑞义[3] 李志凯[3] 朱华青[3] LI Shu-na;SONG Pei;ZHANG Jin-li;HE Xiao-xia;XIE Yi-xin;ZHANG Ya-gang;WANG Rui-yi;LI Zhi-kai;ZHU Hua-qing(School of Chemical Engineering, Xi＇ an University, Xi＇ an Engineering Research Center of Environmental Detection and Food Safety, Xi＇ an 710065, China;College of Chemistry and Chemical Engineering, Xi＇ an University of Science and Technology, Xi＇ an 710054,China;State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China)

机构地区：[1]西安文理学院化学工程学院西安市环境与食品安全检测工程研究中心,陕西西安710065 [2]西安科技大学化学与化工学院,陕西西安710054 [3]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001

出　　处：《燃料化学学报》2018年第5期615-624,共10页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(51704240;21703276;51602253);陕西省自然科学基金(2016JQ2030;2016JQ2017);陕西省教育厅基金(15JK1491);西安市科技计划项目(2017CGWL24;CXY1531WL03);2017年省级大学生创新创业计划项目资助~~

摘　　要：采用水热合成法制备了船形、扁球形及纳米片CeO_2-MnO_x复合氧化物。并运用低温N2吸脱附、XRD、SEM、TEM、H2-TPR、拉曼光谱、XPS等表征技术对不同形貌CeO_2-MnO_x复合氧化物的结构与其低浓度CH4催化燃烧反应性能之间的关系进行了关联。结果表明,CeO_2-MnO_x复合氧化物的形貌与其催化性能密切相关。其中,扁球形CeO_2-MnO_x复合氧化物的氧空位、Ce3+含量及表面吸附活性氧物种最多,其CH4催化燃烧反应活性最高,540℃时,可将CH4完全转化;其次是船形CeO_2-MnO_x复合氧化物催化剂,540℃时其CH4转化率为94.05%;与前两者相比,纳米片CeO_2-MnO_x复合氧化物催化剂的氧空位及表面吸附活性氧物种较少,活性较差,相同反应温度下,其CH4转化率仅为89.68%。Ship-like,oblate spheroid and nano sheet CeO2-MnOxmixed oxides were prepared by hydrothermal method and characterized by N2 sorption, XRD, SEM, TEM, H2-TPR, Raman spectra and XPS. The relationship between the structure of CeO2-MnOxand their catalytic performance in lean methane combustion were then investigated. The results reveal that the catalytic performance of the mixed CeO2-MnOxoxide was greatly depended on its morphology. Among all of the samples,the mixed oblate spheroid CeO2-MnOxoxides with most oxygen vacancies,Ce3＋content and surface active oxygen exhibited the highest activity in lean methane combustion,with a complete CH4 conversion at 540 ℃. Following it,the mixed ship-like CeO2-MnOx oxides catalyst had 94.05% of the CH4 conversion at 540 ℃. On the contrast,the mixed nano sheet CeO2-MnOx oxides catalyst presented the lowest catalytic activity with only 89. 68% CH4 conversion at the same reaction temprature owing to its lower oxygen vacancies and surface active oxygen.

关 键 词：CEO2 MNOX 低浓度甲烷 催化燃烧 形貌 

分 类 号：O643[理学—物理化学]