Effect of Ru loading and of Ru precursor in Ru/C catalysts for ammonia synthesis

被引:48
作者
Rossetti, I [1 ]
Forni, L [1 ]
机构
[1] Univ Milan, Dipartimento Chim Fis & Elettrochim, I-20133 Milan, Italy
关键词
Ru loading; ammonia synthesis; Ru/C catalyst;
D O I
10.1016/j.apcata.2004.12.024
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
One of the key points in the study of Ru/C catalysts for ammonia synthesis is the structure sensitivity of the reaction, which usually determines the proper metal loading, so governing the cost of the final catalyst. In the present work, the effect of Ru loading on catalytic activity and thermal stability (i.e. catalyst resistance against support methanation and metal sintering) was investigated. The optimal Ru loading was found to be around 3.5 wt.%, a value considerably lower with respect to that commonly found in literature. Furthermore, top activity was obtained with 10-15% Ru dispersion, higher dispersion values leading to less performing catalysts. Finally, the effect of some different water-soluble Ru precursors on catalyst behaviour was also investigated. (c) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:315 / 320
页数:6
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