物理化学学报 >> 2011, Vol. 27 >> Issue (11): 26462646-2650..doi: 10.3866/PKU.WHXB20111129

催化和表面科学 上一篇    下一篇

制备方法对Ag-Ru/CeO2氨合成催化剂性能的影响

张留明, 林建新, 王榕, 魏可镁   

  1. 福州大学化肥催化剂国家工程研究中心, 福州 350002
  • 收稿日期:2011-06-11 修回日期:2011-08-19 发布日期:2011-10-27
  • 通讯作者: 林建新 E-mail:lin3jx@fzu.edu.cn
  • 基金资助:

    中国石油科技创新基金(2010D-5006-0502)和国家科技支撑计划(2007BAE08B02)资助项目

Effect of Preparation Methods on the Catalytic Activity of Ag-Ru/CeO2 Catalyst for Ammonia Synthesis

ZHANG Liu-Ming, LIN Jian-Xin, WANG Rong, WEI Ke-Mei   

  1. National Engineering Research Center of Chemical Fertilizer Catalyst, Fuzhou University, Fuzhou 350002, P.R. China
  • Received:2011-06-11 Revised:2011-08-19 Published:2011-10-27
  • Contact: LIN Jian-Xin E-mail:lin3jx@fzu.edu.cn
  • Supported by:

    The project was supported by the Innovation Fund of China National Petroleum Corporation (2010D-5006-0502) and National Science and Technology Support Program of China (2007BAE08B02).

摘要: 采用共沉淀法(CP)、改性沉淀沉积法(MDP)、浸渍法(IP)制备了Ag-Ru/CeO2催化剂, 并运用N2 物理吸附、X射线衍射(XRD)、H2程序升温还原(H2-TPR)、N2程序升温脱附(N2-TPD)等技术对其进行了表征, 考察了不同制备方法对Ag-Ru/CeO2催化剂氨合成性能的影响. 结果表明: 不同方法制备的催化剂, 银助剂对载体的还原性能和氮气的解离吸附性能的影响存在明显的差别, 从而影响了催化剂的氨合成活性, 其中采用浸渍法制备的催化剂氮气解离吸附最强, 载体最易于还原, 因此催化剂低温氨合成活性最高, 在10 MPa, 10000 h-1, 400°C反应条件下, 出口氨浓度达到9.4%.

关键词: 浸渍法, 氨合成, 银, 二氧化铈,

Abstract: Ag-Ru/CeO2 catalysts were prepared by co-precipitation (CP), modified deposition precipitation (MDP), and incipient-wetness impregnation (IP). The obtained catalysts were characterized by N2 physisorption, X-ray diffraction (XRD), H2 temperature-programmed reduction (H2-TPR), and temperatureprogrammed desorption of nitrogen (N2-TPD). The results showed that the ammonia synthesis activity of the Ag-Ru/CeO2 catalyst prepared by incipient-wetness impregnation was 9.4% at 10 MPa, 10000 h-1 and 400°C, which was higher than that obtained by other methods. There were obvious differences in the reduction property of Ru/CeO2 and in the nitrogen dissociation behavior among the catalysts prepared by different methods. Catalyst activity for the catalyst prepared by incipient-wetness impregnation improved greatly at a low reaction temperature. The high catalytic activity was due to the easier reduction of Ag-Ru/ CeO2 and the higher amount of dissociation of chemisorbed nitrogen.

Key words: Incipient-wetness impregnation, Ammonia synthesis, Silver, Ceria, Ru

MSC2000: 

  • O643