Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (06): 1474-1480.doi: 10.3866/PKU.WHXB201203311

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

The Performance of the NOx Storage Capacity and Sulfur Tolerance of the La0.7Sr0.3Co1-xFexO3 Catalyst

MAAi-Jing1, WANG Shao-Zeng1, ZOU Hong-Hu1, MENG Ming1, LI Zhi-Jun2, BAO Jun3, LI Xin-Gang1   

  1. 1. Tianjin Key Laboratory of Applied Catalysis Science & Technology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, P. R. China;
    2. State Key Laboratory of Engines, Tianjin University, Tianjin 300072, P. R. China;
    3. National Synchrotron Radiation Laboratory, University of Science & Technology of China, Hefei 230029, P. R. China
  • Received:2012-01-16 Revised:2012-03-31 Published:2012-05-17
  • Contact: LI Xin-Gang E-mail:xingang_li@tju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20806056, U1162103), National High Technology Research and Development Program of China (863 project) (2008AA06Z323), Natural Science Foundation of Tianjin, China (11JCYBJC03700), Program for New Century Excellent Talents in University of China (NCET-10-0615), Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2011-1568), and State Key Laboratory of Engines, Tianjin University, China (K2012-05).

Abstract: In this paper, a series of La0.7Sr0.3Co1-xFexO3 (x=0, 0.2, 0.6, and 1.0) catalysts was synthesized by a sol-gel method with calcination at 700 °C in static air. The effect of the Fe doping on the structure, the performance of the NOx storage, sulfur tolerance and regeneration of the perovskite catalysts was investigated. Our results showed that the partial substitution of Co with Fe improved the depersion of the SrCO3 phase, and that the perovskite phase became the only species detected from the X-ray diffraction (XRD) patterns. The NOx storage capacity (NSC) of the catalysts dropped following an increase in the proportion of Fe doping. The deposition of sulfate on the surface and the partial structural damage of the La0.7Sr0.3CoO3 catalyst led to a dramatic reduction in the NSC and the NO oxidation capacity after the sulfation treatment: the NSC being reduced by 64.2%, and the conversion of NO-to-NO2 falling to 43.4% from 72.8%. The sulfur tolerance of the perovskite catalyst, however, was improved after doping with Fe at the B sites of the La0.7Sr0.3CoO3 catalyst. Of all of these catalysts, the perovskite with 60% of Fe doping (the Fe60 sample) gave the best performance for sulfur tolerane properties and regeneration ability. The NSC of the Fe60 sample was reduced by only 16.6%, and the NO-to-NO2 conversion reached the value almost similar to that of the fresh sample (i.e. 69.1%).

Key words: Lean-burn, NOx, Storage, Perovskite, Sulfur tolerance, Regeneration, La0.7Sr0.3Co1-xFexO3

MSC2000: 

  • O643