SIZE EFFECTS IN ETHYLENE OXIDATION ON SILVER CATALYSTS - INFLUENCE OF SUPPORT AND CS PROMOTER

被引：93
作者：
GONCHAROVA, SN [1 ]
PAUKSHTIS, EA [1 ]
BALZHINIMAEV, BS [1 ]
机构：
[1] RUSSIAN ACAD SCI, BORESKOV INST CATALYSIS, SIBERIAN BRANCH, NOVOSIBIRSK 630090, RUSSIA
来源：
APPLIED CATALYSIS A-GENERAL | 1995年 / 126卷 / 01期
关键词：
ETHYLENE EPOXIDATION; ETHYLENE PI-COMPLEX; SILVER CATALYST; SILVER PARTICLE SIZE DISTRIBUTION; SIZE EFFECT;
D O I：
10.1016/0926-860X(95)00036-4
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：
A new method for preparing supported silver catalysts with a narrow particle size distribution has been developed. For crystals with a diameter ranging from 100 to 1000 Angstrom the dependencies of reaction rates on size have been studied for epoxidation and deep oxidation of ethylene. For particles 300-500 Angstrom in size the reaction rate was found to increase sharply. The concentration of ethylene pi-complexes with Ag+ cations increased proportionally to the reaction rate. These pi-complexes are assumed to be the only intermediates directing the reaction towards epoxidation. The ratio of the reaction rate to the concentration of pi-complexes was found to remain constant within a wide range of AE crystal sizes including bulk silver samples. The influence of the support (alpha-Al2O3, SiO2) on the size effect relates to the secondary processes of ethylene oxide conversion. The factors that cause the catalytic size effect and the promoting effect of Cs are discussed.
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页码：67 / 84
页数：18
相关论文
共 41 条
  • [1] BELLAMY LD, 1968, ADV INFRARED GROUP F, P54
  • [2] XPS AND UPS STUDIES OF OXYGEN-ADSORPTION OVER CLEAN AND CARBON-MODIFIED SILVER SURFACES
    BORONIN, AI
    BUKHTIYAROV, VI
    VISHNEVSKII, AL
    BORESKOV, GK
    SAVCHENKO, VI
    [J]. SURFACE SCIENCE, 1988, 201 (1-2) : 195 - 210
  • [3] OXYGEN-ADSORPTION ON AG POWDER
    BOWKER, M
    PUDNEY, P
    ROBERTS, G
    [J]. JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS I, 1989, 85 : 2635 - 2640
  • [4] 2 OXYGEN STATES AND THE ROLE OF CARBON IN PARTIAL OXIDATION OF ETHYLENE OVER SILVER
    BUKHTIYAROV, VI
    BORONIN, AI
    SAVCHENKO, VI
    [J]. SURFACE SCIENCE, 1990, 232 (1-2) : L205 - L209
  • [5] BUKHTIYAROV VI, IN PRESS J PHYS CHEM
  • [6] TRANSIENT-RESPONSE AND INFRARED STUDIES OF ETHYLENE-OXIDE REACTIONS ON SILVER CATALYSTS AND SUPPORTS
    BULUSHEV, DA
    PAUKSHTIS, EA
    NOGIN, YN
    BALZHINIMAEV, BS
    [J]. APPLIED CATALYSIS A-GENERAL, 1995, 123 (02) : 301 - 322
  • [7] CAMPBELL CT, 1985, J CATAL, V92, P364
  • [8] THE INFLUENCE OF PARTICLE-SIZE ON THE CATALYTIC PROPERTIES OF SUPPORTED METALS
    CHE, M
    BENNETT, CO
    [J]. ADVANCES IN CATALYSIS, 1989, 36 : 55 - 172
  • [9] CHEIPHEZ LI, 1982, KHIMIYA, P279
  • [10] OXIDATION OF ETHYLENE CATALYZED BY SILVER SUPPORTED ON ZIRCONIUM-PHOSPHATE - PARTICLE-SIZE AND SUPPORT EFFECT
    CHENG, S
    CLEARFIELD, A
    [J]. JOURNAL OF CATALYSIS, 1985, 94 (02) : 455 - 467
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