STRUCTURE AND REACTIVITY OF AMMONIA-SYNTHESIS CATALYSTS DERIVED FROM CERU2 PRECURSORS - A STUDY BY INSITU X-RAY ABSORPTION-SPECTROSCOPY

被引：15

作者：

WALKER, AP

RAYMENT, T

LAMBERT, RM

OLDMAN, RJ

机构：

[1] UNIV CAMBRIDGE,DEPT CHEM,CAMBRIDGE CB2 1EW,ENGLAND

[2] ICI CHEM & POLYMERS,RES & TECH,RUNCORN CB2 1EW,CHESHIRE,ENGLAND

来源：

JOURNAL OF CATALYSIS | 1990年 / 125卷 / 01期

关键词：

D O I：

10.1016/0021-9517(90)90078-X

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：

The activation, steady-state performance, and poisoning of efficient ammonia synthesis catalysts derived from a CeRu2 precursor have been studied by in situ X-ray absorption spectroscopy at 50 bar pressure and at temperatures up to 450°C. The EXAFS and near-edge data supported by earlier XRD studies under identical conditions indicate that the active phase consists of ultradispersed, electron-rich Ru entities with low metal-metal coordination and in intimate contact with the CeH2+x support. Oxidation of this material yields CeO2/Ru; this system is catalytically inert and exhibits none of the unusual structural or electronic properties of the active CeH2+x/Ru catalyst. © 1990.

引用

页码：67 / 76

页数：10

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