PRECIOUS METAL DERIVATIVES

Although the description fulminating is not used and thus confusion with the fulminate not caused, mercury also forms explosive compounds of similar nature. The nitride (ibid.) is the most common and can be formed from the metal and ammonia in some circumstances, causing accidents where mercury manometers are used with ammonia. Halo-hydroxy- and oxy-nitrides can also be involved [3], See METAL FULMINATES, GOLD COMPOUNDS, A-METAL DERIVATIVES, PRECIOUS METAL DERIVATIVES, SILVER COMPOUNDS... 

MOLTEN METAL EXPLOSIONS, PRECIOUS METAL DERIVATIVES PYROPHORIC METALS, REACTIVE METALS STEEL WOOL, THORIUM FURNACE RESIDUES... 

This class of compounds showing explosive instability deals with heavy metals bonded to elements other than nitrogen and contains the separately treated groups GOLD COMPOUNDS LEAD SALTS OF NITRO COMPOUNDS LITHIUM PERALKYLURANATES MERCURY COMPOUNDS METAL ACETYLIDES METAL FULMINATES METAL OXALATES PLATINUM COMPOUNDS PRECIOUS METAL DERIVATIVES SILVER COMPOUNDS... 

See GOLD COMPOUNDS, N-METAL DERIVATIVES, METAL FULMINATES, PRECIOUS METAL DERIVATIVES, SILVER COMPOUNDS... 

Plant cleaning incidents, 330 Platinum compounds, 330 Platinum group metals, 331 Poly(aminium) perchlorates, 331 Polyazacaged metal perchlorates, 332 Polycondensation reaction incidents, 332 Poly(dimercuryimmonium) compounds, 332 Poly(dimethylsilyl)chromate, 333 Polymeric peroxyacids, 333 Polymerisation incidents, 333 Polynitroalkyl compounds, 336 Polynitroaryl compounds, 337 Polynitroazopyridines, 340 Polyperoxides, 341 Polypropylene powder, 342 Precious metal derivatives, 342 Preparative hazards, 342... 

METAL FULMINATES METAL OXALATES PLATINUM COMPOUNDS PRECIOUS METAL DERIVATIVES SILVER COMPOUNDS... 

The direct reductive amination (DRA) is a useful method for the synthesis of amino derivatives from carbonyl compounds, amines, and H2. Precious-metal (Ru [130-132], Rh [133-137], Ir [138-142], Pd [143]) catalyzed reactions are well known to date. The first Fe-catalyzed DRA reaction was reported by Bhanage and coworkers in 2008 (Scheme 42) [144]. Although the reaction conditions are not mild (high temperature, moderate H2 pressure), the hydrogenation of imines and/or enam-ines, which are generated by reaction of organic carbonyl compounds with amines, produces various substituted aryl and/or alkyl amines. A dihydrogen or dihydride iron complex was proposed as a reactive intermediate within the catalytic cycle. 

Na-ZSM-5(a molar SiOz/AlaOa ratio=23.8) provided by Tosoh Corp. was used. ln(4wt%)/H-ZSM-5 and lr(1wt%)/H-ZSM-5 catalysts were prepared by the ion exchange method using NH4-ZSM-5 derived from the Na-ZSM-5 with aqueous solutions of ln(NOs)3 at 368 K for 8 h and lrCI(NH3)sCl2 at room temperature for 24 h, respectively. Addition of precious metals, 1wt% platinum and iridium to ln/H-ZSM-5 was carried out by impregnating the ln/NH4-ZSM-5 in aqueous solutions of Pt(NH3)4Cl2 and lrCI(NH3)5Cl2, respectively. The catalysts were calcined at 813 K for 3 h. 

In Figure 12a (Pd Pt = 1 2) and 12b (Pd Pt = 1 1), only the spectral feature of CO adsorbed on the Pt atoms, i.e., a strong band at 2068 cm and a very weak broad band at around 1880 cm was observed, while that derived from CO adsorbed on Pd atoms at 1941 cm is completely absent, which proved that the Pd-core has been completely covered by a Pt-shell. Recently we also characterized Au-core/Pd-shell bimetallic nanoparticles by the CO-IR [144]. Reduction of two different precious metal ions by refluxing in ethanol/ water in the presence of poly(A-vinyl-2-pyrrolidone) (PVP) gave a colloidal dispersion of core/shell structured bimetallic nanoparticles. In the case of Pd and Au ions, the bimetallic nanoparticles with a Au-core/Pd-shell structure are usually produced. In contrast, it is difficult to prepare bimetallic nanoparticles with the inverted core/shell, i.e., Pd-core/Au-shell structure. A sacrificial hydrogen strategy is useful to construct the inverted core/shell structure, where the colloidal dispersions of Pd cores are treated with hydrogen and then the solution of the second element, Au ions, is slowly... 

Diaminodiphenyl derivatives can be obtained from appropriately substituted nitrobenzenes by a rather dated process of alkaline reduction with zinc powder/ sodium hydroxide solution, which affords hydrazobenzene. A more recent method uses a catalytic reduction process with hydrogen and specifically deactivated catalysts of precious metals. Subsequent acid-catalyzed rearrangement with hydrochloric acid yields the hydrochloride of the target diamine ... 

Ruthenium is derived from platinum metal ores. Method of production depends on the type of ore. However, the extraction processes are simdar to those of other nohle metals (see Platinum, Rhodium and Iridium). Ruthenium, like Rhodium, may he obtained from accumulated anode sludges in electrolytic refining of nickel or copper from certain types of ores. Also, residues from refining nickel by Mond carbonyl process contain ruthenium and other precious metals at very low concentrations. The extraction processes are very lengthy, involving smelting with suitable fluxes and acid treatments. 

Electron microscopic examination of catalyst materials, particularly those containing natural components, permits the identification of their origin. For example, carbons utilized as supports for precious metals in a wide variety of slurry-phase and fixed-bed reactions can be derived from a large number of naturally occurring sources (Fig. 8). The shape, morphology, and composition are useful properties for determining their origin. 

Precious metals Mixed chloride solution (Au, Pt, Pd) 8-Hydroxyquinoline derivatives in aromatic solvent... 

Benzene and its derivatives can be hydrogenated on the surface of precious metals only under pressure, and even then generally only at elevated temperatures (Figure... 

Most catalytic metals and metal oxides are derived from Group VIII of the periodic table. Of special importance are Fe, Co, Ni, Rh, Pd, and Pt but also of importance are Cu and Ag in Group lb, V in Group Vb, and Cr and Mo in Group Vlb. Three of the precious metals Rh, Pd, and Pt are extensively used in many industries due to their extremely high activity and selectivity. They are rare in nature and... 

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