Chinese Journal of Catalysis ›› 2012, Vol. 33 ›› Issue (7): 1075-1079.DOI: 10.1016/S1872-2067(11)60413-0

• Research Briefing • Previous Articles     Next Articles

Ammonia Synthesis over Ruthenium Catalysts using Barium-Doped Zirconia as Supports Prepared by Citric Acid Method

LIN Jianxin*, WANG Ziqing, ZHANG Liuming, NI Jun, WANG Rong, WEI Kemei   

  1. National Engineering Research Center of Chemical Fertilizer Catalyst, Fuzhou University, Fuzhou 350002, Fujian, China
  • Received:2012-04-23 Revised:2012-05-20 Online:2012-06-21 Published:2012-06-21

Abstract: Barium-promoted zirconia (Ba-ZrO2) was synthesized by the citric acid method and used as supports for Ru/Ba-ZrO2 catalysts, which were prepared by incipient wetness impregnation with K2RuO4 as precursor. The obtained Ba-ZrO2 and catalysts were characterized by X-ray diffraction and CO2 temperature-programmed desorption. The effect of Ba content on the structure and catalytic activity of K-Ru/Ba-ZrO2 catalysts is discussed. The formation of BaZrO3 can improve significantly the catalytic activity of Ru/Ba-ZrO2 for ammonia synthesis. The ammonia concentration and rate of ammonia synthesis of the K-Ru/Ba-ZrO2 catalyst (molar ratio of Ba:Zr is 1:1) were 9.24% and 29.77 mmol/(g•h), respectively, at 425 °C, 5.0 MPa, and 10000 h-1. Improvements in electron conductivity and the basic nature of the catalyst may be the main reasons for such high catalytic activity in ammonia synthesis.

Key words: barium, zircona, ruthenium, ammonia synthesis, electronic conductivity