Platinum group elements palladium

Zhu H, Han J, Xiao JQ, Jin Y (2008) Uptake, translocation, and accumulation of manufactured iron oxide nanoparticles by pumpkin plants. J Environ Monit 10 713-717 Zimmerman S, Alt F, Messerschmidt J, Von Bohlen A, Taraschewski H, Sures B (2002) Biological availability of traffic-related platinum-group elements (palladium, platinum, and rhodium) and other metals to the zebra mussel (Dreissena polymorpha) in water containing road dust. Environ Toxicol Chem 21(12) 2713-2718... 

Capobianco, C.H. Drake, M. 1990. Partitioning of ruthenium, rhodium, and palladium between spinel and silicate melt and implications for platinum-group element fractionation trends, Geochimica et Cosmochimica Acta, 54, 869-874. 

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. 

J. Begerow, L. Dunemann, Internal platinum and palladium exposure of the general population with emphasis on the exposure from automobile exhaust and dental restorative alloys, in F. Zereini, F. Alt (eds), Anthropogenic Platinum-group Element emissions. Their Impact on Man and Environment, Springer, Berlin, 2000, pp. 227 D 236. 

Lustig S and Sghramel P (2000) Platinum bioaccumulation in plants and overview of the situation for palladium and rhodium. In Zereini F and Alt F, eds. Anthropogenic platinum-group element emission their impact on man and environment, pp. 95-104, Springer Verlag, Berlin-Hei-delberg. 

The saltiness of the oceans was well known from ancient times and salt was used for domestic uses. But the major composition of sea water was yet to be determined. As early as 1820 William Wollaston, the discoverer of palladium and rhodium, predicted the presence of potassium in sea water and then proceeded to determine its concentration using gravimetric analytical techniques, based on the newly discovered platinum group elements and the formation of potassium-platinum compounds. 

Wang J, Varughese K (1987) Determination of traces of palladium by adsorptive stripping voltammetry of the dimethylglyoxime complex. Anal Chim Acta 199 185-189 Zereini F, Alt F (2(XK)) Anthropogenic platinum-group element emissions. Their impact on man and environment. Springer, Berlin... 

Platinum group elements (PGE) are used as catalysts in a variety of industrial, chemical and pharmaceutical applications, such as in the production of pesticides and dye stuffs and in the processing of polymers. These rare noble metals, notably platinum (Pt), rhodium (Rh) and palladium (Pd), are also used as catalysts in automobile catalytic converters to reduce the emission of carbon monoxide (CO), nitrogen oxides (NOJ and hydrocarbons (HC) in exhaust fumes. This application, in fact, accounts for the largest consumption of the global supply of these metals on a per weight basis. In 2008, for instance, catalytic converter producers consumed a total of 52, 47 and 86% of the world s Pt, Pd and Rh, respectively (Matthey 2008). Pd use by the catalyst industry increased by a factor of six from 1993 to 2008 (Matthey 1996, 2008). 

Ruehle T, Schneider H, Find J, Herein D, Pfaender N, Wild U, Schloegl R, Nachtigall D, Artelt S, Heinrich U (1997) Preparation and characterisation of Pt/A1203 aerosol precursors as model Pt-emissions from catalytic converters. Appl Catal B Environ 14 69-84 Schafer J, Hannker D, EckWdt JD, Stiiben D (1998) Uptake of traffic-related heavy metals and platinum group elements PGE by plants. Sci Total Environ 215 59-67 Speranza A, Leopold K, Maier M, Taddei AR, Scoccianti V (2009) Pd-nanoparticles cause Increased toxicity to kiwifruit pollen compared to soluble Pd. Environ Pollut (submitted) Sures B, Zimmermann S (2007) Impact of humic substances on the aqueous solubility, uptake and bioaccumulation of platinum, palladium and rhodium in exposure studies with Dreissena polymorpha. Environ Pollut 146(2) 444 51... 

Moldovan M, Rauch S, Gomez M, Palacios M, Morrison GM (2001) Bioaccumulation of palladium, platinum and rhodium fixrm urban particulates and sediments by the freshwater isopod Asellus aquaticus. Water Res 35 4175-4183 Moldovan M, Palacios MA, Gomez MM, Morrison G, Rauch S, McLeod C, Ma R, Caroli S, Alimonti A, Petrucci F, Bocca B, Schramel P, Zischka M, Pettersson C, Wass U, Luna M, Saenz JC, Santamarfa J (2002) Environmental risk of particulate and soluble platinum group elements released from gasoline and diesel engine eatalytic converters. Sci Total Environ 296 199-208... 

Rubeanic acid (I) reacts in ammoniacal solution in its aci-form (II) with copper, cobalt and nickel salts giving insoluble colored compounds (see page 329). In solutions containing strong mineral acid, rubeanic acid reacts only with certain elements of the platinum group. With palladium and platinum salts, red crystalline precipitates are obtained they are inner complex salts (III) of a semi-aci-form of rubeanic acid. Ruthenium salts give a soluble blue compound, whose structure is not known. 

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