摘要
为了研究不同制备方法对铈锰固溶体形貌、结构及其表面物种等的影响,阐明铈锰固溶体结构与其催化性能之间的关系,通过纳米铸型法、水热法、共沉淀法、热分解法制备出4种理论掺锰量为15%的铈锰固溶体〔Ce0.85Mn0.15Ox,n(Ce)∶n(Mn)=0.85∶0.15〕。采用XRD、FESEM、TEM、N2-吸附脱附、ICP-OES、XPS对催化剂进行物化性质表征,并以苯甲醇和苯胺偶联反应作为探针反应来评估其催化性能。结果表明,以纳米铸型法制备的铈锰固溶体催化剂具有最佳的催化活性,其苯胺转化率达到了67.9%,N-苄叉苯胺的选择性为99.4%,时空产率为0.56 mmol/(gcat·h)。与用其他3种方法制备的铈锰固溶体相比,纳米铸型法制备的铈锰固溶体具有较大的表面积、特定的介孔结构,催化剂表面拥有较高相对含量的Ce^3+、Mn^3+,有利于吸附和活化氧分子,这些因素均有利于催化醇胺偶联反应。
In order to explore the effects of different preparation methods on the morphology,structure and surface species of cerium-manganese solid solution,and clarify the relationship between the structure and their catalytic performance,four kinds of cerium-manganese solid solution(Ce0.85Mn0.15Ox)samples with a theoretical manganese content of 15%[n(Ce)∶n(Mn)=0.85∶0.15]were prepared by nano-casting method,hydrothermal method,co-precipitation method and thermal decomposition method,respectively.The physical and chemical properties of the catalysts were characterized by XRD,FESEM,TEM,N2 adsorption-desorption,ICP-OES and XPS.The coupling reaction of benzyl alcohol and aniline was used as a probe reaction to evaluate the catalytic performances of the catalysts under air atmosphere.The results showed that the catalyst prepared by nano-casting method possessed the best catalytic activity.The conversion of aniline was 67.9%,the selectivity of N-benzylideneaniline was 99.4%,and the time-space yield was 0.56 mmol/(gcat·h).Compared with those by the other three preparation methods,the cerium-manganese solid solution prepared by nano-casting method had larger surface area,specific mesoporous structure,and higher relative content of Ce^3+and Mn^3+on the catalyst surface,which is conducive to the adsorption and activation of oxygen molecules.All these factors are conducive to the coupling reaction of alcohols with amines.
作者
符淑钗
刘鹏
祝德兴
吴华杰
程高
余林
FU Shuchai;LIU Peng;ZHU Dexing;WU Huajie;CHENG Gao;YU Lin(Key Laboratory of Clean Chemistry Technology of Guangdong Regular Higher Education Institutions,School of Chemical Engineering and Light Industry,Guangdong University of Technology,Guangzhou 510006,Guangdong,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2020年第6期1233-1241,共9页
Fine Chemicals
基金
国家自然科学基金(21576054)
广东省教育厅特色与创新项目(2015KTSCX027)
广东省科技创新战略专项资金(2018A030310563)。
关键词
铈锰固溶体
醇胺偶联反应
亚胺
催化剂
纳米材料
cerium-manganese solid solution
coupling reaction of alcohols with amines
imines
catalysts
nanomaterials
