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Ruthenium palladium containing

All three metals of this group give rise to ammino-derivatives the compositions of which, however, differ considerably. The ammino-derivatives of ruthenium mostly contain a nitroso-group as well as ammonia the ammino-derivatives of rhodium salts closely resemble the cobalt -ammines and the ammino-derivatives of palladium salts correspond to the ammino-derivatives of platinum salts. [Pg.193]

Ammino-derivatives of Ruthenium Halides—Derivatives of Ruthenium Salts containing a Nitroso-group—Ammino-derivatives of Rhodium Salts— Ammino-derivatives of Palladium Salts. [Pg.275]

Liguras et al. investigated platinum, palladium, rhodium and ruthenium catalysts containing lwt.% of the noble metal on an alumina carrier at S/C 1.5 in the... [Pg.78]

It is well established by now that jjn vivo or jji vitro hydrogenation of unsaturated fatty acid residues of lipids can be carried out using complexes of platinum metal ions (mainly rhodium,ruthenium and palladium) containing as ligands various water soluble phosphines Cl], or Alizarin Red (sodium 1,2-di-hydroxyanthraquinone-3-sulfonate, QS), and this method proved to be a fruitful way for investigating the connection between membrane fluidity and the various properties and functions of... [Pg.533]

Coupling reactions of aromatic, heteroaromatic, and vinylic substrates with alkynes via sp C—H bond cleavage under rhodium, iridium, ruthenium, palladium, or nickel catalysis to produce a wide range of cyclic compounds have been described in this chapter. These annulation reactions provide powerful methods for constructing a variety of -rr-conjugated molecules containing fused aromatic and heteroaromatic nuclei from simple, readily available substrates. Extensive efforts will continue to be made to extend the scope of starting materials for this catalysis. [Pg.716]

In molecules containing both an acetylenic and a nitro function, either or both may be reduced. Preferential reduction of the acetylenic function is best achieved with palladium (42,44). Ruthenium, on the other hand, favors selective reduction of an aromatic nitro function high yields of (3-aminophenyljacetylene were obtained from the corresponding nitro compound. Catalyst life is prolonged by protection of the acetylenic function (70). Cobalt polysulffde and ruthenium sulffde catalysts have been used similarly, but more vigorous conditions are required (100°C, 25-70 atm) (71). [Pg.109]

The corrosion behaviour of amorphous alloys has received particular attention since the extraordinarily high corrosion resistance of amorphous iron-chromium-metalloid alloys was reported. The majority of amorphous ferrous alloys contain large amounts of metalloids. The corrosion rate of amorphous iron-metalloid alloys decreases with the addition of most second metallic elements such as titanium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, copper, ruthenium, rhodium, palladium, iridium and platinum . The addition of chromium is particularly effective. For instance amorphous Fe-8Cr-13P-7C alloy passivates spontaneously even in 2 N HCl at ambient temperature ". (The number denoting the concentration of an alloy element in the amorphous alloy formulae is the atomic percent unless otherwise stated.)... [Pg.633]

For the noble metals used in oxidation, the loading is about 0.1 oz per car, with calls for a million ounces per year. The current world production rates of platinum, palladium, and rhodium are 1.9, 1.6, and 0.076 million ounces respectively the current U,S. demand for platinum, palladium, rhodium, and ruthenium are 0.52, 0.72, 0.045, and 0.017 million ounces respectively (72, 73). The supply problem would double if NO reduction requires an equal amount of noble metal. Pollution conscious Japan has adopted a set of automobile emission rules that are the same as the U.S., and Western Europe may follow this creates a demand for new car catalysts approaching the U.S. total. The bulk of world production and potential new mines are in the Soviet Union and South Africa. The importation of these metals, assuming the current price of platinum at 155/oz and palladium at 78/oz, would pose a balance of payment problem. The recovery of platinum contained in spent catalysts delivered to the door of precious metal refiners should be above 95% the value of platinum in spent catalysts is greater than the value of lead in old batteries, and should provide a sufficient incentive for scavengers. [Pg.81]

Non-ionic thiourea derivatives have been used as ligands for metal complexes [63,64] as well as anionic thioureas and, in both cases, coordination in metal clusters has also been described [65,66]. Examples of mononuclear complexes of simple alkyl- or aryl-substituted thiourea monoanions, containing N,S-chelating ligands (Scheme 11), have been reported for rhodium(III) [67,68], iridium and many other transition metals, such as chromium(III), technetium(III), rhenium(V), aluminium, ruthenium, osmium, platinum [69] and palladium [70]. Many complexes with N,S-chelating monothioureas were prepared with two triphenylphosphines as substituents. [Pg.240]

There has been great interest in the preparation of bimetallic transition metal cluster complexes containing palladium.899-902 Bimetallic palladium-ruthenium clusters have been shown to be good precursors to supported bimetallic catalysts.903,904... [Pg.648]

When we first contemplated thermochemical products available from Glu, a search of the literature revealed no studies expressly directed at hydrogenation to a specific product. Indeed, the major role that Glu plays in hydrogenation reactions is to act as an enantioselectivity enhancer (17,18). Glu (or a number of other optically active amino acids) is added to solutions containing Raney nickel, supported nickel, palladium, or ruthenium catalysts and forms stereoselective complexes on the catalyst surface, leading to enantioselective hydrogenation of keto-groups to optically active alcohols. Under the reaction conditions used, no hydrogenation of Glu takes place. [Pg.157]

Mishchenko, A. P. and M. E. Sarylova. 1981. Hydrogen permeability and catalytic activity of a membrane catalyst from a palladium alloy containing 6% ruthenium in relation to hydrogenation of 1,3-pcntadicnc. Met. i Splavy Membrane Kak. Katalyz. M. 75-81. [Pg.146]

This article presents the principles known so far for the synthesis of metal complexes containing stable carbenes, including the preparation of the relevant carbene precursors. The use of some of these compounds in transition-metal-catalyzed reactions is discussed mainly for ruthenium-catalyzed olefin metathesis and palladium-Znickel-catalyzed coupling reactions of aryl halides, but other reactions will be touched upon as well. Chapters about the properties of metal- carbene complexes, their applications in materials science and medicinal chemistry, and their role in bioinorganic chemistry round the survey off. The focus of this review is on ZV-heterocyclic carbenes, in the following abbreviated as NHC and NHCs, respectively. [Pg.3]

The initial steps are similar to any other mineral extraction process. This involves crushing mineral, froth flotation, gravity concentration and other steps to obtain platinum metal concentrates that may contain about 30 to 40 wt% of platinum group metals. The concentrate is treated with aqua regia to separate soluble metals, gold, platinum, and palladium from other noble metals such as ruthenium, rhodium, iridium, osmium, and silver that remain in... [Pg.687]

In 1828 Berzelius and G. W. Osann (25), professor of chemistiy at the University of Dorpat, examined the residues left after dissolving crude platinum from the Ural mountains in aqua regia. Berzelius did not find in them any unusual metals except palladium, rhodium, osmium, and iridium, which had already been found by Wollaston and Tennant in similar residues from American platinum. Professor Osann, on the other hand, thought that he had found three new metals, which he named pluranium, ruthenium, and polinium (25, 36). In 1844, however, Professor Klaus, another Russian chemist showed that Osann s ruthenium oxide was very impure, but that it did contain a small amount of a new metal (26,33). [Pg.440]

Transition metal catalyzed reactions are becoming commonplace in synthetic chemistry. Heterogeneous or homogeneous catalysts containing valuable metals such as palladium, platinum, rhodium and ruthenium are frequently used in the manufacture of active pharmaceutical ingredients (API).[1] The use of such catalysts can lead to metal contamination of the product. The amount of precious... [Pg.493]


See other pages where Ruthenium palladium containing is mentioned: [Pg.936]    [Pg.717]    [Pg.48]    [Pg.264]    [Pg.348]    [Pg.76]    [Pg.197]    [Pg.18]    [Pg.969]    [Pg.76]    [Pg.162]    [Pg.938]    [Pg.165]    [Pg.176]    [Pg.119]    [Pg.127]    [Pg.172]    [Pg.464]    [Pg.360]    [Pg.1003]    [Pg.1036]    [Pg.202]    [Pg.259]    [Pg.293]    [Pg.647]    [Pg.78]    [Pg.191]    [Pg.528]    [Pg.1344]    [Pg.10]    [Pg.792]    [Pg.39]    [Pg.46]    [Pg.166]    [Pg.678]   
See also in sourсe #XX -- [ Pg.390 ]




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