Hexachloroplatinate IV

The filtrate contains an appreciable quantity of Mo3+. For economy, these liquids from several preparations may be combined and evaporated to 40 ml. and the procedure repeated. The liquids should be kept in an atmosphere of nitrogen if they are to be kept longer than 1 day. 

Submitted by LAWRENCE E. COX and DENNIS G. PETERS Checked by J. IIALPERNf and M. PRIBANICt 

None of the accepted preparative methods12 for disodium hexa-chloroplatinate(IV), Na2[PtCl6], is entirely suitable for routine use, because these procedures require reaction of a mixture of solid sodium chloride and platinum metal with chlorine gas at temperatures near 500°. However, a preparation of the desired compound is described below which yields a product of very high purity and which is much more convenient than those previously reported since only solution chemistry is involved. Unlike the corresponding ammonium and potassium salts, disodium hexachloroplatinate(IV) exhibits high solubility in water and in several nonaqueous solvents, including ethanol, methanol, and Ar,/V-dimethylformamide—a fact which enables one to extend the range of studies of the chemistry of hexachloroplatinate(IV). 

High-purity (99.99%) platinum in the form of either thin wire or foil is recommended as a starting material because of its ease of dissolution in aqua regia all other chemicals should be of reagent-grade quality and are usable without additional purification. 

A solution of hexachloroplatinic(IV) acid, H2PtCl6, is prepared by dissolving 4.5 g. f of platinum metal in 50-100 ml. of a 1 1 mixture of concentrated hydrochloric and nitric acids. The dissolution is carried out in a two-necked, round-bottomed, 250-ml. Pyrex flask equipped with a reflux condenser. The aqua regia solution is evaporated almost to dryness four times with successive 50-ml. portions of concentrated hydrochloric acid. 

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The PGM concentrate is attacked with aqua regia to dissolve gold, platinum, and palladium. The more insoluble metals, iridium, rhodium, mthenium, and osmium remain as a residue. Gold is recovered from the aqua regia solution either by reduction to the metallic form with ferrous salts or by solvent-extraction methods. The solution is then treated with ammonium chloride to produce a precipitate of ammonium hexachloroplatinate(IV),... 

C3H5KOS2 140-89-6) see Cefaclor Omeprazole Pantoprazole sodium Protizinic acid Pyritinol potassium hexachloroplatinate(IV)... 

Dipping solution Mix 3 ml 10 < 0 hexachloroplatinic(IV) acid solution with 97 ml 10potassium iodide solution [43]. 

Variant Mix 45 ml 10% aqueous potassium iodide solution with 2.5 ml 10% hexachloroplatinic(IV) acid solution and make up to 200 ml with water (pH 2.52) [44]. 

Spray solution Add 3 ml 10% hexachloroplatinic(IV) acid solution to 100 ml 6% aqueous potassium iodide solution and dilute with 97 ml water [3, 8, 35, 36, 45]. 

Note Tertiary amines and quaternary ammonium compounds yield stronger colors than primary amines [25]. The dipping solution can also be used as spray solution [44]. Other reagent compositions have also been reported in the literature (1, 3, 6, 12, 13, 15, 18, 21, 23, 41] In some cases the reagents have been made up in acetone [38, 39], methanol [14] or ethanol [37] and/or acidified with hydrochloric acid [3, 33, 37-40]. The concentrations of hexachloroplatinic(IV) acid have been in the range of 0.05 -0.4 those of potassium iodide between 0.5 and 24spray solution containing 2% potassium iodide and 0.23170 hexachloroplatinic(IV) acid hexahydrate in N-hydro-chloric acid is reported to yield the best coloration results with respect to detection sensitivity and color differentiation in the detection of morphine, codeine, quinine, methadone and cocaine [46]. Acidic reagent solutions have been recommended for benzodiazepines [10, 11]. Sulfones do not react [39]. 

Reagent 2 Spray solution 2 lYeat 3 ml hexachloroplatinic(IV) acid solution... 

Pt/Pd bimetallic nanoparticles can be prepared by refluxing the alcohol/water (1 1, v/v) solution of palla-dium(II) chloride and hexachloroplatinic(IV) acid in the presence of poly(A-vinyl-2-pyrrolidone) (PVP) at ca. 95 °C for Ih [15,16,48]. The resulting Pd/Pt nanoparticles have a Pt-core/Pd-shell structure with a narrow size distribution and the dispersion is stable against aggregation for several years. The core/shell structure was confirmed by the technique of EAXFS. Composition of Pt/Pd nanoparticles can be controlled by the initially feed amount of two different metal ions, i.e., in this case one... 

Coreduction of Mixed Ions. Coreduction of mixed ions is the simplest method to synthesize bimetallic nanoparticles. However, this method cannot be always successful. Au/Pt bimetallic nanoparticles were prepared by citrate reduction by Miner et al. from the corresponding two metal salts, such as tetrachloroauric(III) acid and hexachloroplatinic(IV) acid (24). Reduction of the metal ions is completed within 4 h after the addition of citrate. Miner et al. studied the formation of colloidal dispersion by ultraviolet-visible (UV-Vis) spectrum, which is not a simple sum of those of the two monometallic nanoparticles, indicating that the bimetallic nanoparticles have an alloy structure. The average diameter of the bimetallic nanoparticles depends on the metal composition. By a similar method, citrate-stabilized Pd/Pt bimetallic nanoparticles can also be prepared. 

Coreduction of Au and Pt ions by refluxing alcohol in the presence of PVP gives the colloidal dispersions of Au-core/Pt-shell structured bimetallic nanoparticles, as mentioned before. The formation of this bimetallic nanoparticles was traced by in situ UV-Vis spectra (68). The spectral change is shown in Figure 9.1.15, in which the peaks ascertained to be the metal ions disappear at first, and then the broad tailing peaks due to the colloidal dispersions appear. More precisely speaking, the tetrachloroauric(III) acid (at —320 nm) is reduced first, followed by reduction of hexachloroplatinic(IV) acid (at —265 nm). This order of reduction is consistent with the standard redox potential of the two metal ions. After the reduction of two... 

Potassium hexachloroplatinate (IV) [16921-30-5] NI 486.0. Crystd from water (20ml/g) between 100° and 0°. 

Platinised asbestos is prepared by soaking 3g of asbestos in 7ml of 10% hexachloroplatinic (IV) acid, evaporating the mixture to dryness, and igniting the residue at red heat. 

Hydrogen hexachloroplatinate(IV)-Copper(II) chloride, H2PtCl6-CuCl2. 

Hydrogen hexachloroplatinate(IV)-Diethoxymethylsilane, 76 Hydroxylation Osmium tetroxide, 186 Osmium tetroxide-N-Methylmorpho-line N-oxide, 222... 

Potassium nitrosodisulfonate, 258 other methods Bis(tributyltin) oxide, 41 /-Butyl hydroperoxide-Dichlorotris-(triphenylphosphine)rutheni-um(II), 54 Dibutyltin oxide, 95 Hydrogen hexachloroplatinate(IV)-Copper(II) chloride, 145 4-Methoxy-2,2,6,6-tetramethy 1-1 -oxopiperidinium chloride, 183 of alcohols to carboxylic acids Cetyltrimethylammonium permanganate, 69... 

Hydrogen hexachloroplatinate(IV)-Copper(II) chloride, 145 Lead tetraacetate-Manganese(II) acetate, 157... 

Platinum Compounds Hydrogen hexachloroplatinate(IV)-Copper(II) chloride, 145 Hydrogen hexachloroplatinate(IV)-Diethoxymethylsilane, 76 Platinum-Titanium, 251 Rhodium Compounds [2,2 -Bis(diphenylphosphine)-l,T-binaphthyl](dimethanol)rhodium(I) perchlorate, 36... 

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