Based on water-gas shift reaction mechanism and perovskite compounds characteristics, La1-xCexFeO3 (.K) perovskite were designed and prepared as shift catalysts. DTA and XRD results reveal that La1-xCexFeO3 can be formed at 730~760 ℃ by mechanic-mix thermal decomposition method. Activity and heat-resisting tests show that La1-xCexFeO3 (.K) possess high thermal stability if x is less than or equals to 0.5. But when x is greater than 0.5, La1-xCexFeO3 (.K) will be converted into ceria and magnetite partially or completely under shift reaction conditions. In the case of x=0.5, the conversion of CO is about 68% at 530 ℃. Potassium can greatly improve the low temperature activity, but slightly reduces the high temperature activity, and has little impact on the thermal stability. La0.5Ce0.5FeO3 (.K) is a promising chromium-free high temperature shift catalyst.
参考文献
[1] | 郑起,徐建本,魏可镁,魏明灯,林性贻.无铬CO高温变换催化剂的研究Ⅱ.过渡元素对高变催化剂结构与性能的影响[J].催化学报,1999(01):21-24. |
[2] | Mou Z H J;Diao L T;Liu Q S H .Industrial applications of chromium-free iron-based CO high temperature shift catalyst in normal pressure system[J].Chemical Fertilizer Industry(in Chin),2001,28(03):40. |
[3] | 郭益群,苏运来,许群,李利民,王文祥.铈对氧化铁吸附性能的影响[J].中国稀土学报,1998(02):131. |
[4] | 苏运来,马卓娜,杜宝石,郭益群,胡捷.铈对铁系无铬变换催化剂还原的影响[J].中国稀土学报,2001(03):272-274. |
[5] | Zhang Xuetong;Jin Hengfang;Zhang Qiancheng .Study on the CoO promoter in iron-based CO shift catalyst[J].Industrial Catalysis,2001,9(05):36. |
[6] | 马红钦,谭欣,朱慧铭,张鎏,张晓军.新型无铬高变催化剂的研究开发[J].工业催化,2002(06):15-18. |
[7] | Rethwisch D G;Dumesic J A .The effect of metal-oxygen bond strength on properties of oxides Ⅱ Water-gas shift reaction over bulk oxides[J].Applied Catalysis,1986,21:97. |
[8] | Taihei;Nitadori;Makoto Misono .Catalytic properties of La1-xA′xFeO3 (A′=Sr, Ce) and La1-xCexCoO3[J].Journal of Catalysis,1985,93:459. |
[9] | Dou Bosheng;Fan Zhirong;Wu Yue .Ammonia oxidation over mixed metal oxide: perovskite La1-xSrxCoO3-λ[J].Chinese Journal of Catalysis(in Chinese),1985,6(04):299. |
[10] | Marcos J A;Buitrago R H;Lombardo E A .Surface chemistry and catalytic activity of La1-ySryCoO3 perovskite (M=Sr or Th) Ⅰ. Bulk and surface reduction studies[J].Journal of Catalysis,1987,105:95. |
[11] | 马红钦,谭欣,朱慧铭,张继炎,张鎏.La1-xCexFeO3钙钛石高变催化剂的XPS研究[J].中国稀土学报,2003(04):445-448. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%