Gravimetric palladium

Cyclohexane-1,2-dione dioxime (nioxime) (IV) is more soluble in water (8.2 g L 1 at 21 °C) than is dimethylglyoxime it is an excellent reagent for the gravimetric determination of palladium. 

The naphtho[2,3-cf][2,l,3]selenadiazole forms two stable complexes with PdCl2 which serve as the basis of five analytical procedures (gravimetric, spectrophotometric, radiometric, fluorometric and atomic absorption) for the specific determination of macro to submicro quantities of palladium (70MI42600). 

Estimation.—Palladium may be estimated gravimetrically by addition of potassium chloride and alcohol to a concentrated solution of palladium chloride in hydrochloric acid. The brown precipitate of potassium chlor-palladite is collected, ignited, the potassium chloride washed out, and the residual palladium weighed as metal. -... 

Thiopyrylium salts can find application in analytical chemistry. Thus, 2,4,6-triphenylthiopyrylium chloride can be used as a precipitant for the quantitative gravimetric determination of anions (CIO4", 103 , NOj , BF4 ) (87MI3). Thiopyrylium salts can be also used in the spectrophoto-metric determination of bismuth (75URP482648), tellurium (77URP-558856), palladium (77URP558865), and alkyl sulfates (91URP1675746). 

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. 

ISO 11490 1995 Determination of palladium in palladium jewelry alloys - gravimetric determination with dimethylglyoxime... 

In this work, the mechanism of methane oxidation over PCI/AI2O3 catalyst is investigated, the palladium oxidation state under stream reaction is identified and the reactive form of oxygen is determined. XPS, thermal gravimetric and surface potential measurements are performed on this catalyst under various dynamic gaseous treatments. 

Iridium is best determined gravimetrically as Ir02, which can be reduced to the metal. There are no specific gravimetric reagents for iridium. Spectrophotometrically, the [IrCle] complex can be used to determine iridium, or the reagent SnBr2 can be used if rhodium, palladium, and platinum are absent. 

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