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Raney gold

Particles of Raney copper, modified by redox deposition of ruthenium, platinum, or gold were characterized by energy dispersive spectroscopy. Ruthenium is deposited preferentially on the rims of the copper particles while low Miller-index planes are totally free of deposited ruthenium atoms. For platinum or gold the deposition can occur over the whole copper surface [11]. [Pg.222]

AIRBORNE COPPER SLAG-iMILLED P 1721 GOLD GOLD BRONZE KAFAR COPPER Ml (COPPER) M2 (COPPER) OFHC Cu RANEY COPPER... [Pg.383]

In the case of powder bulk catalysts, Cu Raney was modified by direct redox reaction between reduced copper and the salt of a noble metal M (Ru, Pt and Au) [5, 7]. Typically the Cu-M bimetallic catalysts were obtained by mixing a freshly prepared Cu Raney with an aqueous solution of the noble metal salt. When the amount of M is in excess compared to the number of copper surface atoms, it appears that ruthenium deposition is restricted to approximately 1/3 of the copper surface atoms. For platinum and gold, a deposit larger than a monolayer is obtained, indicating that subsurface copper atoms are involved in direct redox reaction. This result is explained by the lower potential difference between copper and rathenium compared to those of copper and platinum or gold [7j. However, the reactions involved in the direct redox reaction may not be as simple as indicated in Section 9.2. A typical time distribution of ion concentrations in solution during the preparation of Cu-Pt is shown in Fig. 9.1. It can be observed that platinum ions disappear very rapidly from the solution while at the same time copper... [Pg.285]

Synonyms Arwood copper Bronze powder Cl 77400 Copper bronze Copper-milled Gold bronze Kafar copper Pigment metal 2 Raney copper... [Pg.1045]


See other pages where Raney gold is mentioned: [Pg.45]    [Pg.374]    [Pg.45]    [Pg.374]    [Pg.134]    [Pg.168]    [Pg.64]    [Pg.242]    [Pg.243]    [Pg.135]    [Pg.157]    [Pg.26]    [Pg.2259]   
See also in sourсe #XX -- [ Pg.374 ]




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