采用固相反应法合成了钙铝石材料12SrO·7Al_2O_3,并以此作为涂层制备了堇青石蜂窝陶瓷型La_(0.8)Sr_(0.2)MnO_3整体催化剂,在不同温度(850～1050℃)下对该催化剂进行了热处理,并采用N2吸附-脱附、X射线衍射和扫描电镜等手段对其进行了表征,考察了其催化甲基丙烯酸甲酯燃烧反应的活性.结果表明,12SRO·7Al_2O_3作为涂层明显改善了整体催化剂的热稳定性,在850℃下焙烧6 h后,含有12SrO·7Al_2O_3涂层的整体催化荆在260℃即可将甲基丙烯酸甲酯完全转化.12SrO·7Al_2O_3涂层可避免La_(0.8)Sr_(0.2)MnO_3活性组分与堇青石的接触,减轻了活性组分在催化荆表面的烧结,有利于保持La_(0.8)Sr_(0.2)MnO_3活性组分的晶体结构和分散度,提高整体催化剂的活性和热稳定性.
12SrO·Al_2O_3 was synthesized by solid reaction and was used as the washcoat to a La_0.8Sr_0.2MnO_3-cordierite monolith catalyst.The monolith catalyst was treated at difierent temperatures(850-1050℃)and Was characterized by N_2 adsorption.desorption,X-ray diffraction.and scanning electron microscopy .The catalytie activity of the monolith catalyst was evaluated using methyl methacrylate combustion.The results showed that the 12SrO·7Al_2O_3 washcoat improved the thermal stability of the monolith catalyst obviously.After eaicination at 850℃ for 6 h,the monolith catalyst with the 12SrO·7Al_2O_3 washcoat could fully convert methyl methacrylate at about 260 ℃.The 12SrO·7Al_2O_3 prevented the interaction between La_0.8Sr_0.2MnO_3 and cordierite and alleviated the sintering of La_0.8Sr_0.2MnO_3,and thus kept the structure and the dispersion of La_0.8Sr_0.2MnO_3 and enhanced the activity and thermal stability of the monolith catalyst.
参考文献
| [1] | Libby W F .[J].Science,1971,171:499. |
| [2] | Cimino S;Pirone R;Russo G .[J].Industrial and Engineering Chemistry Research,2001,40:80. |
| [3] | LiWB;ZhuangM;Xiao T C;Green M L H .[J].Journal of Physical Chemistry B,2006,110:21568. |
| [4] | Alifanti M;Florea M;Parvulescu VI .Ceria-based oxides as supports for LaCoO3 perovskite; catalysts for total oxidation of VOC[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2007(26):400-405. |
| [5] | Misono M .[J].Caml Today,2009,144:285. |
| [6] | Vergunst T;Kapteijn F;Moulijn J A .[J].Applied Catalysis A:General,2001,213:179. |
| [7] | Kucharczyk B;Tylus W .[J].Catalysis Today,2008,137:318. |
| [8] | Zou H.;Ge X.;Shen JY. .Surface acidity and basicity of gamma-Al2O3 doped with K+ and La3+ and calcined at elevated temperatures[J].Thermochimica Acta: An International Journal Concerned with the Broader Aspects of Thermochemistry and Its Applications to Chemical Problems,2003(1/2):81-86. |
| [9] | 刘晓军,于海燕,杨毅宏,吴玉胜,张林楠,毕诗文.氧化镧修饰活性氧化铝载体的孔结构[J].稀土,2006(06):37-40. |
| [10] | 官芳,卢晗锋,黄海凤,刘华彦,张泽凯,陈银飞.六铝酸盐作涂层的蜂窝陶瓷型La0.8Sr0.2MnO3催化剂热稳定性[J].高校化学工程学报,2008(06):954-959. |
| [11] | Hayashi K;Ueda N;Matsuishi S;Hiano M Kamiya T Hosono H .[J].Chemistry of Materials,2008,20:5987. |
| [12] | Yeh T F;Lee H G;Chu K S;Wang C B .[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,2004,384:324. |
| [13] | Shimokawa H;Kusaba H;Einaga H;Teraoka Y .[J].Catalysis Today,2008,139:8. |
| [14] | Arendt E;Maione A;Klisinska A;Sanz O Montes M Suarez S Blaneo J Ruiz P .[J].Applied Catalysis A:General,2008,339:1. |
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