催化学报 ›› 2012, Vol. 33 ›› Issue (2): 281-289.DOI: 10.1016/S1872-2067(11)60335-5

• 研究论文 • 上一篇    下一篇

柠檬酸络合法制备的 Co/CeO2 催化剂上中温乙醇水蒸气重整性能

庞潇健, 陈亚中*, 代瑞旗, 崔鹏   

  1. 合肥工业大学化工学院, 安徽合肥230009
  • 收稿日期:2011-09-15 修回日期:2011-10-26 出版日期:2012-02-20 发布日期:2015-07-27

Co/CeO2 Catalysts Prepared Using Citric Acid Complexing for Ethanol Steam Reforming

PANG Xiaojian, CHEN Yazhong*, DAI Ruiqi, CUI Peng   

  1. School of Chemical Engineering, Hefei University of Technology, Hefei 230009, Anhui, China
  • Received:2011-09-15 Revised:2011-10-26 Online:2012-02-20 Published:2015-07-27

摘要: 采用柠檬酸络合法制备了 Co/CeO2 及其钙掺杂系列催化剂, 并对催化剂进行了低温 N2 物理吸附、X 射线衍射、H2 程序升温还原、傅里叶变换红外光谱、高分辨透射电镜表征以及乙醇水蒸气重整催化性能测试. 结果表明, 所制 Co/CeO2 催化剂具有良好的乙醇水蒸气重整催化性能, 500 oC 时乙醇能全部转化为 C1, 氢气产率高达 85% 以上. Ca 掺杂减小了载体 CeO2 纳米颗粒尺寸, 但对还原后 Co0 尺寸的影响较小. 当 Ca 掺杂量大于 5.0% 时, 催化剂氧化还原性能和乙醇水蒸气重整催化性能下降. 较高的还原温度有利于体相 Ce4+ 还原为 Ce3+, 并且提高了催化活性, 认为金属-氧化物边界的增加提高了催化活性. 初步稳定性考察结果表明, 5% 钙掺杂后的催化剂具有更好的抗积炭性能.

关键词: 钴, 氧化铈, 氧化钙掺杂, 柠檬酸络合, 乙醇水蒸气重整, 中温

Abstract: Co/CeO2 catalysts with and without calcium doping were prepared by the citric acid complexing method, and characterized by N2 adsorption, X-ray diffraction, temperature-programmed reduction, Fourier transform infrared spectroscopy, and high resolution transmission electron microscope. Their catalytic performance measurement for ethanol steam reforming (ESR) at 400–650 oC and atmospheric pressure with a steam-to-carbon ratio of 3.0 and gas hourly space velocity of 50000 ml/(g·h) was measured. The citric acid complexing method enhanced metal-support interaction. The Co/CeO2 catalysts gave almost 100% ethanol conversion and good hydrogen yield at 500 oC. Calcium doping in the catalyst reduced the particle size of CeO2, but had little effect on the metallic cobalt size after reduction. Calcium doping higher than 5% deteriorated the redox properties and ESR catalytic performance, which was attributed to the fouling of CeO2 by CaO. Catalysts activated at 650 oC showed a better performance, which was due to a higher reduction degree of ceria and increase of the metal-oxide interface. Stability investigation of the catalysts suggested that 5% calcium doping enhanced carbon deposition resistance.

Key words: cobalt, ceria, calcium doping, citric acid complexing, ethanol steam reforming, intermediate temperature