Estimation of Effective Diffusivity of Stored NOx in the Barium Phase of Pt/BaO/Al2O3 Catalysts using TAP

被引：7
作者：
Kumar, Ashok [1 ]
Harold, Michael P. [1 ]
Balakotaiah, Vemuri [1 ]
机构：
[1] Univ Houston, Dept Chem & Biomol Engn, Houston, TX 77204 USA
来源：
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH | 2010年 / 49卷 / 21期
关键词：
TRAP CATALYSTS; STORAGE; REDUCTION; H-2; REGENERATION; MONOLITH; PT/AL2O3; PT/BA/AL2O3; DISPERSION; RESOLUTION;
D O I：
10.1021/ie100504q
中图分类号：
TQ [化学工业];
学科分类号：
0817 ;
摘要：
A systematic study over Pt/BaO/Al2O3 powder catalyst is carried out using Temporal Analysis of Products (TAP) to estimate the effective diffusivity of stored NOx in the barium phase. The prenitration of Pt/BaO/Al2O3 using sequential pulses of NO, followed by reduction with H-2 results in the evolution of N-2 and NH3. The reduction is carried out in the NOx transport limited regime in which diffusion of the stored NOx from BaO storage phase to Pt/BaO interface was determined to be the rate controlling process. The effluent profiles of N containing species (2N(2) + NH3) were used to estimate stored NOx diffusivity in barium phase and the apparent activation energy. The activation energy (74-81 kJ/mol) is in good agreement with the estimated value of 75 kJ/mol from a recent NOx trap modeling study.(1)
引用
收藏
页码：10334 / 10340
页数：7
相关论文
共 25 条
  • [1] Modeling the effect of Pt dispersion and temperature during anaerobic regeneration of a lean NOx trap catalyst
    Bhatia, Divesh
    Harold, Michael P.
    Balakotaiah, Vemuri
    [J]. CATALYSIS TODAY, 2010, 151 (3-4) : 314 - 329
  • [2] The surface structure of BaO on Pt(111): (2x2)-reconstructed BaO(111)
    Bowker, Michael
    Stone, Peter
    Smith, Rupert
    Fourre, Elodie
    Ishii, Masaru
    de Leeuw, Nora H.
    [J]. SURFACE SCIENCE, 2006, 600 (10) : 1973 - 1981
  • [3] The effect of proximity between Pt and BaO on uptake, release, and reduction of NOx on storage catalysts
    Cant, Noel W.
    Liu, Irene O. Y.
    Patterson, Michael J.
    [J]. JOURNAL OF CATALYSIS, 2006, 243 (02) : 309 - 317
  • [4] Pt dispersion effects during NOx storage and reduction on Pt/BaO/Al2O3 catalysts
    Clayton, Robert D.
    Harold, Michael P.
    Balakotaiah, Vemuri
    Wan, C. Z.
    [J]. APPLIED CATALYSIS B-ENVIRONMENTAL, 2009, 90 (3-4) : 662 - 676
  • [5] NOx storage and reduction with H2 on Pt/BaO/Al2O3 monolith: Spatio-temporal resolution of product distribution
    Clayton, Robert D.
    Harold, Michael P.
    Balakotaiah, Vemuri
    [J]. APPLIED CATALYSIS B-ENVIRONMENTAL, 2008, 84 (3-4) : 616 - 630
  • [6] Ammonia is a hydrogen carrier in the regeneration of Pt/BaO/Al2O3 NOx traps with H2
    Cumaranatunge, L.
    Mulla, S. S.
    Yezerets, A.
    Currier, N. W.
    Delgass, W. N.
    Ribeiro, F. H.
    [J]. JOURNAL OF CATALYSIS, 2007, 246 (01) : 29 - 34
  • [7] Overview of the fundamental reactions and degradation mechanisms of NOx storage/reduction catalysts
    Epling, WS
    Campbell, LE
    Yezerets, A
    Currier, NW
    Parks, JE
    [J]. CATALYSIS REVIEWS-SCIENCE AND ENGINEERING, 2004, 46 (02): : 163 - 245
  • [8] NOx removal catalysis under lean conditions
    Forzatti, P.
    Castoldi, L.
    Nova, I.
    Lietti, L.
    Tronconi, E.
    [J]. CATALYSIS TODAY, 2006, 117 (1-3) : 316 - 320
  • [9] Temporal analysis of products (TAP)-Recent advances in technology for kinetic analysis of multi-component catalysts
    Gleaves, John T.
    Yablonsky, Gregory
    Zheng, Xiaolin
    Fushimi, Rebecca
    Mills, Patrick L.
    [J]. JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL, 2010, 315 (02) : 108 - 134
  • [10] TEMPORAL ANALYSIS OF PRODUCTS (TAP) - A UNIQUE CATALYST EVALUATION SYSTEM WITH SUBMILLISECOND TIME RESOLUTION
    GLEAVES, JT
    EBNER, JR
    KUECHLER, TC
    [J]. CATALYSIS REVIEWS-SCIENCE AND ENGINEERING, 1988, 30 (01): : 49 - 116
123