Platinum-group metals working

There are several exceUent sources of information about the platinum-group metals. The exceUent reference work G. Wilkinson, R. D. GiUard, and J. A. McCleverty, eds.. Comprehensive Coordination Chemistry Pergamon Press, Oxford, U.K., 1987, contains iadividual chapters devoted to descriptive chemistry of each element. 

Two works provide exceUent coUections of articles describiag important modem appfications of PGMs. These are E. H. Hardey, ed.. The Chemistry of Platinum Group Metals, Elsevier, 1991, and Gmelin Handbook of Inorganic Chemistry Platinum Suppl Vol. Al, Sptinger-Vedag, New York, 1986. 

CO adsorption on electrochemically facetted (Clavilier), 135 Hamm etal, 134 surfaces (Hamm etal), 134 Platinum group metals in aqueous solutions, 132 and Frumkin s work on the potential of zero charge thereon, 129 Iwasita and Xia, 133 and non-aqueous solutions, 137 potentials of zero charge, 132, 137 preparation of platinum single crystals (Iwasita and Xia), 133 Platinum-DMSO interfaces, double layer structure, 141 Polarization time, 328 Polarons, 310... 

The catalysis field began in the nineteenth century with work on heterogeneous platinum group metals from such contributors as Berzelius, Faraday, Dobereiner, Mitscherhch, Davy, Sabatier, and Ostwald [1, 2]. Iridium never held a very high place in the field, however, because it showed no special advantages. Rylander expresses this point well in his classic 1967 work on heterogeneous catalysis [3],... 

Carbon monoxide is the molecule whose adsorptive properties have certainly been investigated in most detail. A review of the work prior to 1970 was published by Ford (2) in this series, but in the interim so much additional information has been obtained that a complete compilation of the data would be far beyond the scope of this article. Instead, the main emphasis will be given to a discussion of essential features that fortunately have much in common with different platinum group metals as well as with various crystal planes. 

Each category, by itself, can be a topic for a separate symposium, and it is hoped that in the future such symposia will be forthcoming. The topics chosen were such that they would cover a broad area of the chemistry of platinum group metals. The session on industrial aspects was included to enable scientists in industry to present their views on the problems that are facing the industry and perhaps stimulate sufficient interest so that newer applications could be developed in the future. It is also hoped that such a forum would enable scientists in industry to summarize broadly the work carried out by them without worry about violation of proprietary nature of the work. 

What the authors have particularly in mind here as being desirable is the kind of bibliography exemplified by Howe s Bibliography of the Metals of the Platinum Group, a work covering some 150 years (14), beginning around 1750. Unfortunately, there are few compilations so meticulously done. 

That this never transpired is one of the ironies of chemical history. What phosphine complexes have enabled us to do has been much more significant. Chatfs early work concentrated on platinum group metals, and this was consonant with the interest in complexes containing hydrides, olefins, alkyl groups, or aryl groups. When Chatt left The Frythe, the work had just about reached the iron group, with minor excursions beyond. 

In this respect palladium is superior to all other platinum group metals, but it cannot be used because of its fast dissolution under working conditions. On the other hand, it has been known that certain amorphous alloys have extremely high corrosion resistance (S). These facts led to the studies of amorphous palladium-based alloys as anode materials in the electrolysis of soda. 

This work demonstrates that supported heterogeneous Platinum Group Metal catalysts are very effective for the selective oxidation of primary alcohols to aldehydes and secondary alcohols to ketones using air as the oxidant. 

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