Platinum distribution/Groups

Suitable starting materials for the Kolbe electrolytic synthesis are aliphatic carboxylic acids that are not branched in a-position. With aryl carboxylic acids the reaction is not successful. Many functional groups are tolerated. The generation of the desired radical species is favored by a high concentration of the carboxylate salt as well as a high current density. Product distribution is further dependend on the anodic material, platinum is often used, as well as the solvent, the temperature and the pH of the solution." ... 

Holwell, D.A. McDonald, I. 2007. Distribution of platinum-group elements in the Platreef at Overysel, northern Bushveld Complex a combined PGM and LA-ICP-MS study. Contributions to Mineralogy and Petrology, 154, 171-190. 

Dionne, N. J., and Rhodin, T.N. (1974). d-band contributions to the energy distribution of field-emitted electrons from platinum-group metals. Phys. Rev. Lett. 32, 1311-1314. 

Speciation and distribution of Group 8,9 and 10 elements (platinum group elements)... 

Distributions of the platinum group elements (PGEs) are shown in Fig. 12.8. The distribution of ruthenium (Ru) is unknown, but concentrations are estimated to be less than 50 fmol kg-1. The distributions of rhodium (Rh) and palladium (Pd) (Period 5) show significant surface depletions relative to deep waters and overall concentrations are somewhat less than 1 pmol kg 1. 

ICP-MS is useful for analysis of catalysts from two perspectives The composition of the catalysts must be carefully controlled, particularly because the active elements are often expensive. The catalysts are often finely distributed in a substrate material so their concentration in the bulk material may be quite low. Second, catalysts, particularly those used in automotive catalytic converters, can be a significant source of platinum group elements in the environment. Re and Pt have been measured in catalysts by ICP-MS [193], Procedures for the analysis of used catalytic converter materials by ICP-MS have been reported [355]. Accurate measurements are essential for many of these applications so isotope dilution-based concentration calibration is commonly used. 

Cicchella, D., Fedele, L., De Vivo, B., Albanese, S., and Lima, A. (2008a). Platinum group element distribution in the soils from urban areas of Campania region (Italy). Geochem. Explor. Environ. Anal. 8, 31—40. 

Schafer, J., and Puchelt, H. (1998). Platinum-group-metals (PGM) emitted from automobile catalytic converters and their distribution in roadside soils. J. Geochem. Explor. 64, 307—314. 

T. Hees, B. Wenclawiak, S. Lustig, P. Schramel, M. Schwarzer, M. Schuster, D. Verstraete, R. Dams, E. Helmers, Distribution of Platinum Group Elements (Pt, Pd, Rh) in environmental and clinical matrices composition, analytical techniques and scientihc outlook, Environ. Sci. Pollut. Res., 5 (1998), 105D111. 

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