Adsorption of NO on Cu exchanged zeolites, an FTIR study: Effects of Cu levels, NO pressure, and catalyst pretreatment

被引:132
作者
Cheung, T
Bhargava, SK
Hobday, M
Foger, K
机构
[1] CSIRO,DIV MAT SCI & TECHNOL,CLAYTON,VIC 3168,AUSTRALIA
[2] ROYAL MELBOURNE INST TECHNOL,DEPT APPL CHEM,MELBOURNE,VIC 3001,AUSTRALIA
关键词
D O I
10.1006/jcat.1996.0029
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Three different copper zeolite systems (Cu-ZSM5, Cu-UHSY, and Cu-mordenite) have been prepared with different copper loadings from low to over exchange levels. The surface chemistry of three systems has been studied using IR spectra of adsorbed NO. Most of the copper in Cu-ZSM5 was in the form of Cu(I). Cu(II) species were predominant in Cu-mordenite. For Cu-UHSY the number of Cu(I) species increased as the level of copper loading increased. The catalytic activity for NO decomposition appeared to depend on a Cu(I)- redox cycle which resulted in the formation of an ON-Cu2+-NO2- complex, previously postulated as the critical intermediate in the reaction. Both oxidation and regeneration of the Cu(I) sites in Cu-ZSM5 occurred readily. In Cu-UHSY oxidation was low, suggesting that Cu(I) species were more stable. Cu(II) was the prominent copper species in Cu-mordenite, and regeneration of the Cu(I) sites was difficult. Stability, oxidation, and regeneration of Cu(I) sites play a major role in NO decomposition. In over-exchanged Cu-ZSM5, the Cu(I) sites were more stable, and the rate of oxidation was high. Furthermore a large number of reduced sites were readily regenerated from the Cu(II), thus making it the most effective catalyst for the decomposition of NO. (C) 1996 Academic Press Inc.
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页码:301 / 310
页数:10
相关论文
共 27 条
  • [1] AIRNAZMI A, 1973, J CATAL, V30, P55
  • [2] PREPARATION AND CHARACTERIZATION OF THE CU+/ZSM-5 CATALYST AND ITS REACTION WITH NO UNDER UV IRRADIATION AT 275 K - IN-SITU PHOTOLUMINESCENCE, EPR, AND FT-IR INVESTIGATIONS
    ANPO, M
    MATSUOKA, M
    SHIOYA, Y
    YAMASHITA, H
    GIAMELLO, E
    MORTERRA, C
    CHE, M
    PATTERSON, HH
    WEBBER, S
    OUELLETTE, S
    FOX, MA
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (22) : 5744 - 5750
  • [3] ENVIRONMENTAL CATALYSIS
    ARMOR, JN
    [J]. APPLIED CATALYSIS B-ENVIRONMENTAL, 1992, 1 (04) : 221 - 256
  • [4] ELECTRON-PARAMAGNETIC RESONANCE STUDY OF CU+-NO COMPLEX IN A Y-TYPE ZEOLITE
    CHAO, CC
    LUNSFORD, JH
    [J]. JOURNAL OF PHYSICAL CHEMISTRY, 1972, 76 (11) : 1546 - &
  • [5] PHOTOCATALYTIC DECOMPOSITION OF NITROUS-OXIDE ON CU ION-CONTAINING ZSM-5 CATALYST
    EBITANI, K
    MOROKUMA, M
    KIM, JH
    MORIKAWA, A
    [J]. JOURNAL OF CATALYSIS, 1993, 141 (02) : 725 - 728
  • [6] THE INTERACTION OF NO WITH COPPER IONS IN ZSM5 - AN EPR AND IR INVESTIGATION
    GIAMELLO, E
    MURPHY, D
    MAGNACCA, G
    MORTERRA, C
    SHIOYA, Y
    NOMURA, T
    ANPO, M
    [J]. JOURNAL OF CATALYSIS, 1992, 136 (02) : 510 - 520
  • [7] INFRARED SPECTRUM OF MATRIX-ISOLATED (NO)2
    GUILLORY, WA
    HUNTER, CE
    [J]. JOURNAL OF CHEMICAL PHYSICS, 1969, 50 (08) : 3516 - &
  • [8] SOLID-STATE LA-139 NMR INVESTIGATION OF LANTHANUM-EXCHANGED Y-ZEOLITES
    HERREROS, B
    MAN, PP
    MANOLI, JM
    FRAISSARD, J
    [J]. JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1992, (06) : 464 - 466
  • [9] IWAMOOT M, 1992, J PHYS CHEM-US, V96, P8360
  • [10] CATALYTIC DECOMPOSITION OF NITRIC-OXIDE OVER COPPER(II)-EXCHANGED Y-TYPE ZEOLITES
    IWAMOTO, M
    YOKOO, S
    SAKAI, K
    KAGAWA, S
    [J]. JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS I, 1981, 77 : 1629 - 1638