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6301187 
Book/Book Chapter 
Chapter 9 Preparation of supported catalysts 
1993 
1 
Studies in surface science and catalysis
ISSN: 0167-2991 
Elsevier 
Amsterdam, Netherlands 
Studies in Surface Science and Catalysis 
79 
335-360 
English 
This chapter discusses the preparation of supported catalysts. Many industrially used, high-loading supported catalysts are produced by selective removal of mainly water and oxygen, and sometimes, carbon dioxide, from a nonporous precursor material. An old, but still very important example is the ammonia synthesis catalyst. The starting material of this catalyst is a melt of magnetite (Fe3O4), alumina, and potassium oxide produced in an electric furnace in a nonoxidizing atmosphere at about 1500°C. Utilization of magnetite, or a corresponding mixture of iron and iron oxides is required to dissolve the alumina. Other catalysts used in large-scale processes are produced starting from coprecipitates. Instances are the Ni/alumina (methane) steam reforming catalyst and Cu(oxide)-Zn oxide / alumina catalysts applied in the low-temperature CO shift reaction and in methanol synthesis. The ions of the active component(s) and of the support are precipitated together as hydroxides or hydroxy salts (for example, hydroxyl carbonates), using NaOH or NaHCO3 as the precipitating agent. 
Moulijn, JA; van Leeuwen, PWNM; van Santen, RA 
9780444892294