121Sb,123Sb AND209Bi NQR spectra of antimony(III) and bismuth(III) ethylenediaminetetraacetate compounds

A¹²¹Sb,¹²³Sb, and²⁰⁹Bi NQR spectral study was carried out on SbHEDTA·nH₂O, BiHEDTA·nH₂O(n=2, 0), MBiEDTA·H₂O, M₂Bi(OH)EDTA·nH₂O (n=3,1, M=K,NH₄), and K₂BiFEDTA·3H₂ O. Piezoelectric properties were found in MHEDTA·2H₂O (M=Sb,Bi) and SbHEDTA. The temperature range of the piezoelectric phase for SbHEDTA was found to be 100–270 K.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1915–1918, August, 1989.     

Extraction into methyl isobutyl ketone of metal complexes with ammonium pyrrolidine dithiocarbamate formed in strongly acidic media

It is shown that stable metal complexes with ammonium pyrrolidine dithiocarbamate (APDC) are formed in strongly acidic (0.5–6 M) solutions and can be extracted into methyl isobutyl ketone (MIBK), although APDC is normally used for extractions from solutions at pH 2–12. Percentage extraction curves are presented for 24 elements (Ag, As, Au, Bi, Cd, Co, Cu, Fe, Ga, Ge, Hg, In, It, Ni, Os, Pb, Pd, Pt, Rh, Ru, Sb, Sn, Tl and Zn) from solutions of hydrochloric or nitric acid with and without addition of APDC. Some elements (e.g., Fe, Ga, Ge, In and Au) show identical extractions as their chloro complexes in hydrochloric acid with or without APDC. Others (e.g., Ni, Cu, Pd, As, Ag, Sb, It, Hg and Bi) are strongly extracted (K_d ? 20), from 2 M hydrochloric or nitric acid in the presence of APDC. Palladium (K_d = 8000), Sb (K_d = 10 000), and Bi (K_d = 3500) are particularly easily extracted. The potential of the extraction system was tested by extraction and quantification of palladium from the CANMET standard ore PTC-1; the mean value found was 12.55 μg g^?1 (ppm) palladium with a relative standard deviation of 7.6% (n = 12) and a relative error of 1.2% from the recommended value of 12.70 μg g^?1.     

Spektrochemische Bestimmung von Spurenelementen in reinem Gold

Zusammenfassung Eine Spektrochemische Methode zur Bestimmung von Spuren der Elemente As, Sb, Fe, Mn, Pb, Ni, Bi, Cu, Pt, Pd, Cd, Rh und Ag in reinem Gold wird beschrieben. Zunächst wird das Gold durch Extraktion aus 3 N HCl mit Methylisobutylketon abgetrennt. Die Verunreinigungselemente werden dann an spektralreinem Graphitpulver mit 4% NaCl und 0,02% Co als Bezugselement adsorbiert und im Wechselstromabreißbogen 3,5 min bei 10 A angeregt. Die Spektren wurden mit einem UV-Spektrograph Q 24 auf ORWO-Spektralplatten Blau Extrahart aufgenommen. Die quantitative Bestimmungsgrenze für Mn, Pt und Ag beträgt 10^–6%, für Fe, Pb, Ni, Bi, Cu, Pd und Rh 10^–5% und für As, Sb und Cd 10^–4%. Die relative Standardabweichung überschreitet nicht 30%.

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Spectrochemical determination of trace elements in pure gold

A spectrochemical method for the determination of traces of As, Sb, Fe, Mn, Pb, Ni, Bi, Cu, Pt, Pd, Cd, Rh and Ag in pure gold is described. The gold is first separated by extraction into methyl isobutyl ketone from 3 N HCl solution and then the trace elements are adsorbed on spectrally pure carbon powder containing 4% NaCl and 0.02% Co as reference standard, and excited in an 10 A a.c. arc for 3.5 min. Emission spectra were recorded on ORWO-Blau Extrahart plates with an UV-spectrograph Q 24. Limits of detection were 10^–6% for Mn, Pt and Ag; 10^–5 % for Fe, Pb, Ni, Bi, Cu, Pd and Rh; 10^–4% for As, Sb and Cd. Relative standard deviation was not exceeding 30%.

     

Systematic investigations of the multi-element preconcentration from copper by precipitation of the matrix as copper(I) oxide and copper(I) thiocyanate

Two methods for multi-element preconcentration from copper by reductive matrix precipitation are presented. In systematic investigations on the coprecipitation behaviour of Ag, Al, Au, Bi, Cd, Co, Cr, Fe, Ga, In, Mn, Mo, NJ, Pb, Sb, Se, Sn, Te and Zn during precipitation of the copper matrix as Cu₂O or CuSCN, the separation parameters were optimized. By combination with a hexamethyleneammonium hexamethylenedithiocarbamate collector precipitation, a concentration of 8 elements (Cu₂O precipitation) or 13 elements (CuSCN precipitation) in a small volume was achieved. The limits of detection of the procedures are, depending on the element, 0.1–5 μg g^?1 for flame atomic absorption spectrometry (AAS) and 0.01–0.1 μg g^?1 for graphite furnace AAS. The relative standard deviations are about 3%. The analytical performance of the procedures is compared with that of an electrolytic copper separation.     

Extraktions-Flammenabsorptionsbestimmung von Spurenverunreinigungen in Salzen

Zusammenfassung Spurenverunreinigungen von Fe, Cu, Pb, Ni, Co, Cd, Zn wurden in KH₂PO₄, KNa-Tartrat, BaCl₂, CaCl₂, Citronensäure, Li₂CO₃, Na₂CO₃, K₂CO₃, BaCO₃ und CaCO₃ durch Flammenatomabsorption nach Extraktionsanreicherung mit Diethylammonium-N,N-diethyldithiocarbamat/MIBK bestimmt. Der Einfluß der Salz-matrix auf die Extraktion und Bestimmung der Elementspuren wurde untersucht. Die Methode erlaubt die Bestimmung von 5 · 10^–6–5 · 10^–7% der Elemente mit guter Präzision und Richtigkeit (rel. Standardabweichung 2–7%).

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Extraction flame atomic-absorption determination of microtraces in salts

Summary The trace content of Fe, Cu, Pb, Ni, Co, Cd, Zn in KH₂PO₄, KNa-tartrate, BaCl₂, CaCl₂, citric acid, Li₂CO₃, Na₂CO₃, K₂CO₃, BaCO₃ and CaCO₃ is determined by flame atomic-absorption spectrometry after preceding preconcentration of the traces using the extraction system diethylammonium-N,N-diethyldithiocarbamate/ MIBK. The influence of the salt matrix on the extraction and determination of the traces was investigated. The method permits the determination of 5·10^–6–5·10^–7% of the elements with good precision and accuracy (relative standard deviation 2–7%).

     

Extraction-flame atomic absorption determination of microtraces of copper, zinc, nickel, cobalt, manganese and iron in some alkali salts

Summary The microtrace content of Cu, Zn, Ni, Co, Mn and Fe in NaClO₄, KCl, KOH and KAl(SO₄)₂ · 12 H₂O is determined by flame atomic absorption spectrometry after preceding preconcentration of the traces using the extraction system PMBP/MIBK. It is proved that the salt matrix does not affect the quantitative extraction of the traces. The method permits the determination of the traces in the concentration range of 10^–3–10^–6% with good precision (variation coefficient 2–8%) and accuracy.

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Extraktions-Flammenatomabsorptions-Bestimmung von Mikrospuren von Cu, Zn, Ni, Co, Mn und Fe in Alkali-Salzen

Zusammenfassung Der Mikrospurengehalt von Cu, Zn, Ni, Co, Mn und Fe in NaClO₄, KCl, KOH, und KAl(SO₄)₂ · 12H₂O wurde durch Flammenatomabsorption nach Extraktionsanreicherung mit einer 1-Phenyl-3-methyl-4-benzoylpyrazolon-5 (PMBP)-Lösung in MIBK bestimmt. Die Salz-Matrix weist keinen störenden Einflu\ auf die quantitative Extraktion der Elementspuren auf. Die Bestimmung der Spuren im Konzentrationsgebiet von 10^–3–10^–6% erfolgt mit guter PrÄzision (Variationskoeffizient 2–8%) und Richtigkeit.

     

Element Fractionation in Suspended Matter in Landfill Leachate Using Single Extractions

This study presents the determination of the pseudo-total and available element contents in suspended matter in leachate using stripping voltammetry (DPASV) on a hanging mercury drop electrode and an inductively coupled plasma mass spectrometer (ICP-MS). The following elements were studied: Zn, Pb, As, Sb, Co, Cu, Ni, Cr, Sn, Mo and Cd. To determine the pseudo-total metal contents, we applied microwave digestion using a mixture of HNO₃ and HClO₄ with a small quantity of HF. To assess the metal availability from suspended matter in leachate, the single extraction procedure with 0.1mol·L^–1 acetic acid and 0.01mol·L^–1 ammonium acetate was applied. Metal bioavailability based on single extraction with 15% H₂O₂ was determined. We also estimated the association with particular phases of suspended matter in leachate.     

Kathodenstrahlpolarographische Bestimmung von Spurenelementen in Tetrachlorogolds?ure nach ionenaustausch-chromatographischer Trennung

Zusammenfassung Die kathodenstrahlpolarographische Bestimmung von Ni, Pb, Cu, Co, Fe, Mo, Te, Sn, Zn, Bi, Cd, Tl in Tetrachlorogoldsäure wird beschrieben. Die Nachweisgrenzen liegen im 10^–4%- bzw. 10^–5%-Bereich (Ni, Co, Mo). Die Spuren werden über einen Ionenaustauscher AG 1X8 untereinander und von der Matrix getrennt.

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Cathode-ray polarographic determination of trace elements in tetrachloroauric acid after separation by ion exchange

A method is described for the cathode-ray polarographic determination of traces of Ni, Pb, Cu, Co, Fe, Mo, Te, Sn, Zn, Bi, Cd, Tl in H(AuCl₄). Gold is separated from the trace metals by absorption on the strongly basic anion-exchange resin AG 1X8. The detection limits are within the ranges of 10^–4% and 10^–5% ((Ni, Co, Mo).

     

Extraction system for flame atomic absorption spectrometric analysis of high-purity bismuth compounds

Two new ligands, 2-(2-benzoxazolyl)cyanoacetaldehyde and 2-(2-benzoxazolyl)malonaldehyde are proposed for extractive separation and preconcentration. The extraction behaviour of Ag, Bi, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Pd, Pt, Sb and Zn with respect to pH, salt concentration and the presence of various masking agents was studied. A simple extraction procedure for the analysis of high-purity bismuth compounds was developed.     

Preconcentration neutron activation analysis of trace elements in surface waters by coprecipitation with pyrrolidinedithiocarbamate in the presence of Bi(III)

A simple preconcentration method is described for the simultaneous coprecipitation of Cd(II), Co(II), Cu(II), Mo(VI), U(VI), V(V) and Zn(II) from surface water samples followed by quantitation using neutron activation analysis. Ammonium pyrrolidinedithiocarbanate (APDC), anthranilic acid and 8-hydroxyquinoline have been investigated as possible coprecipitating agents. The suitability of Bi³⁺, Fe³⁺, Ni²⁺ and Pb²⁺ ions as metal carriers has also been studied. It has been found that the above elements can be quantitatively coprecipitated with APDC in the presence of Bi³⁺ carrier at pH 4. The precision and accuracy of the method for all elements are found to be between ±2 and 10%. The enrichment factors are of the order of 10³. The detection limits are in the ppb range varying between 0.04 ng · ml^–1 for Co and V and 5 ng · ml^–1 for Zn. The method has been applied to tap and well waters, and river and lake water samples collected from Halifax County, Nova Scotia.     

Gamma-ray induced decomposition of some divalent and trivalent nitrates

Gamma-ray induced decomposition of some divalent nitrates, viz. Mg(NO₃)₂·6H₂O, Ca(NO₃)₂·4H₂O, Sr(NO₃)₂, Ba(NO₃)₂, Zn(NO₃)₂·6H₂O, Cd(NO₃)₂·4H₂O, Hg(NO₃)₂·2H₂O, Mn(NO₃)₂·4H₂O, Cu(NO₃)₂·3H₂O and trivalent nitrates, viz. Al(NO₃)₃·9H₂O, Fe(NO₃)₃·9H₂O, Cr(NO₃)₃·9H₂O, Y(NO₃)₃·6H₂O, In(NO₃)₃·3H₂O, La(NO₃)₃·6H₂O, Ce(NO₃)₃·6H₂O, Pr(NO₃)₃·6H₂O, Bi(NO₃)₃·5H₂O has been studied in solid state at room temperature. G(NO ₂ ^– ) values (after applying appropriate dose correction) have been found to vary in the range 0.12–3.16 and 0.069–2.15 for divalent and trivalent nitrates respectively. G'-values were calculated by dividing G by the ratio of number of electrons in nitrate ion to the total number of electrons in the nitrate salt. Cation size, its polarizing power, available free space in the crystal lattice and the number and location of water molecules seem to play a dominant role in radiolytic decomposition. For Zn, Sr, In, La and Ce nitrates dose variation studies have been carried out.     

Multi-element preconcentration from technical alkali silicates

Summary After evaporation of the matrix SiO₂ as SiF₄ traces of Ag, Au, Bi, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Pd, Sn, Tl, V and Zn can be preconcentrated from water glasses with recoveries R_s 95% by collector precipitation with hexamethyleneammonium - hexamethylenedithiocarbamate and indium as collector element (Se and Te with varying recoveries between 90 and 95%). The relative standard deviation of the combined method of sample decomposition, preconcentration and AAS-determination is generally about 5% (n=17); the detection limits were found to be between 0.01 and 2 g·g^–1 (3s, n=24). The accuracy of the determination step was verified by analysing the trace concentrates by AAS, ICP-OES and TR-XFS.     

Water-vapor pressure and thermodynamics of the dehydration of manganese,nickel, cadmium,and lead perchlorate hydrates

The water-vapor pressure has been measured by a static method, the temperature limits for existence have been determined, and the parameters of the equation lgp [Torr]=b —a/T have been calculated for the following crystal hydrates: Mn(ClO₄)₂ · 2H₂O (90–130°C, a=3527.0,b=8.487), Ni(ClO₄)₂ · 4H₂O (60–100°C,a=3606.7,b=9.704), Ni(C1O₄)₂ · 2H₂O (110–160°C,a = 4261.7,b = 10.103), Cd(ClO₄)₂ · 6H₂O (25–58.2°C,a = 3143.7,b = 9.356), Cd(ClO₄)₂ · 2H₂O (90–144.8°C,a=3823.3,b = 9.472), Pb(ClO₄)₂ · 3H₂O (10–47°C,a = 2932.9,b = 9.391 and 47–81.5°C,a = 2448.1,b=7.877), Pb(ClO₄)₂ · H₂O (60–102.4°C,a=3610.2,b = 9.857). A hitherto unknown metastable hydrate Cd(ClO₄)₂ · 4H₂O with a phase transition at 30.9°C (20–30.9°C,a = 3669.5,b = 11.343 and 30.9–63.7°C,a=3058.6,b = 9.339) has been detected.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 466–470, March, 1993.     

Determination of Trace Elements in Arsenic and Antimony Minerals by Atomic Absorption Spectrometry and k0-Instrumental Neutron Activation Analysis After Removal of As and Sb

The content of trace elements in arsenic and antimony minerals from the Allchar mine, Macedonia, was determined by electrothermal atomic absorption spectrometry (ETAAS) and k₀-instrumental neutron activation analysis (k₀-INAA) after removal of arsenic and antimony. Their direct determination by ETAAS or k₀-INAA in arsenic (realgar and orpiment) and antimony (stibnite) minerals is limited by strong matrix interferences from As and Sb. Successful elimination of both elements was realized by the extraction of their iodide complexes into toluene. It was found that the optimal conditions were triple extraction of arsenic into toluene from 6mol·L^–1 HCl with addition of KI. Triple extraction of antimony was most successful in the system 4.5mol·L^–1 H₂SO₄ and KI into toluene. In both cases, trace elements (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were then detected in the aqueous phase by ETAAS. The proposed procedures with ETAAS were checked by the method of standard additions and Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn determined in realgar, orpiment and stibnite. Using k₀-INAA the trace elements Ba, Ce, Co, Cr, Cs, Fe, Hg, Sc, Tb, Th, U and Zn in realgar and orpiment were determined before and after As and Sb removal from the same aliquot of sample. The removal of both elements with KI into toluene was higher than 99.8% and no losses of trace elements were observed.     

Infrared spectra (700–200 cm−1) and6Li/7Li and H2O/D2O isotope effects for four isotopically substituted lithium formate monohydrates

The infrared spectra, in the 700–200 cm^–1 region, have been reported for⁶LiHCO₂ · H₂O,⁶LiHCO₂ · D₂O,⁷LiHCO₂ · H₂O and⁷LiHCO₂ · D₂O and the observed fundamental bands have been discussed taking into account the⁶Li/⁷Li and H₂O/D₂O isotope wavenumber shifts on the fundamental vibrations.

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Infrarotspektren (700–200 cm^–1) und⁶Li/⁷Li- und H₂O/D₂O-Isotopeneffekte für vier isotopensubstituierte Lithiumformat-monohydrate

Zusammenfassung Die Infrarotspektren in der Region von 700–200 cm^–1 werden für⁶LiHCO₂ · H₂O,⁶LiHCO₂ · D₂O,⁷LiHCO₂ · H₂O und⁷LiHCO₂ · D₂O angegeben und die beobachteten Grundschwingungen zusammen mit den isotopischen Verschiebungen der Wellenzahlen diskutiert.

     

Oxo-tricyano complexes of molybdenum(IV) with salicylaldehydehydrazone

[Mo(CN)₄O(H₂O)]^2– reacts with hydrazine and salicylaldehyde in aqueous solution to give [Mo(CN)₃O(salhy)]^2– (Hsalhy = salicylaldehydehydrazone), isolated as green (Ph₄P)₂[Mo(CN)₃O(salhy)] · 6H₂O. In CHCl₃, the product converts within seconds into (Ph₄P)₂[Mo(CN)₃O(salhy)] · H₂O · 2CHCl₃ yielding microcrystals having a metallic golden sheen. The complexes were characterised by elemental analysis, t.g. and d.t.a., u.v.–vis. absorption, i.r., ¹H-n.m.r. spectroscopy and by magnetic susceptibility measurements. The visible spectra in various solvents are dominated by the metal-to-ligand charge-transfer bands with absorption maxima linearly dependent on the Reichardt E _T parameter. In halogenated alkanes, the unusual hipsochromic band shift is interpreted in terms of possibile solvent bonding to the metal centre. Cyclic voltammetry indicates that the salt undergoes reversible one electron oxidation with E _1/2 = –0.473 V in DMSO versus ferrocene.     

Liquid — Liquid extraction of silver(I) by diphenyl-2-pyridylmethane in benzene from aqueous mineral acid — Thiocyanate solutions

Liquid — liquid extraction of Ag(I) by diphenyl-2-pyridylmethane (DPPM) in benzene from aqueous nitric and sulfuric acid solutions containing thiocyanate ions has been studied at ambient temperature (24±2 °C). The metal is extracted quantitatively from 0.01M HNO₃+0.02M KSCN; or 0.25M H₂SO₄+0.02M KSCN by 0.1M DPPM (optimum extraction conditions). Slope analysis indicates that two types of ion-pair complexes i.e. [(DPPMH)⁺·Ag(SCN) ₂ ^– ] and [(DPPMH) ₂ ⁺ ·Ag(SCN) ₃ ^2– ] are involved in the extraction process. Separation factors determined at optimum conditions reveal the separation of Ag(I) from Cs(I), Br(I), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Fe(III), Au(III) (from HNO₃ solution only), Cr(III), Hf(IV), Ta(V), Sn(IV) and Cr(VI). With the exception of thiosulfate, other complexing anions like ascorbate, acetate, citrate, oxalate do not hinder the extraction of Ag(I) under optimum conditions.     

Bismuthiol I as an analytical reagent

Summary Bismuth and palladium have been determined volumetrically after precipitation as bismuthiol I complexes. From 0.1 N hydrochloric acid solutions they are separated from Fe²⁺, Al, Cr, Ce³⁺, Zr, Ti, Zn, Th, UO₂ ²⁺, Be, Mg, Mn, Co, Ni, alkalis, alkaline and rare earths.A mixture of tartrate or citrate and EDTA has been found to be useful for the separation of palladium at a p_H 3.5–8.5 from As, Zn, Bi, Sn⁴⁺, Sb, Fe³⁺, Tl⁺, Cu²⁺, Cd, Pb, Ru³⁺, Os⁴⁺, PO₄ ^3–, Ce⁴⁺, Ir⁴⁺, Rh³⁺, VO₃ ^–, CrO₄ ^2–, AsO₄ ^3–, WO₄ ^2–, MoO₄ ^2– and from all the other ions referred to above. Potassium iodide at p_H 6.0–8.0 and thiosulphate at 6–7 keep Ag, Pb, Hg²⁺ and Au³⁺, Ir⁴⁺, Os⁴⁺ respectively in solution and thus allow a selective precipitation of palladium.Hg²⁺, Pb, Cu²⁺, Ag, Tl⁺, Cd and Pd when present along with bismuth are first removed by the reagent and from the filtrate bismuth is estimated. Sn²⁺, Sb³⁺, Fe³⁺, F^–, VO₃ ^–, PO₄ ^3–, AsO₄ ^3– and CrO₄ ^2– interfere in bismuth determination while only Sn²⁺, Pt⁴⁺ and CN^– interfere in palladium estimation.     

Structures of Bismuth(III) Complexonates in Aqueous Solutions Studied by 1H NMR Method

Aqueous solutions of bismuth(III) nitrilotriacetates BiNta · 2H₂O and M₃Bi(Nta)₂ ·nH₂O (M = Na, K, Rb, Cs, NH₄, CN₃H₆, n = 0–4) and the K[Bi(Edta)(Tu)₂] complex (Edta^4– is the anion of ethylenediaminetetraacetic acid, Tu is thiocarbamide) are studied by the ¹H NMR method at room temperature in the pH interval from 2 to 11. The formation of two types of bismuth nitrilotriacetate complexes in solutions is established. They are characterized by the presence (type 1) or absence (type 2) of the Bi–N bond. Their ratio, depending on the composition and pH of the solution, is determined. The K[Bi(Edta)(Tu)₂] compound in solutions occurs as one form. The pH values at which the substance begins to decompose are determined for each compound.     

Cation-exchange separation and colorimetric determination of some elements in trace analysis of platinum-rhodium (10%) alloys

Summary A method of separation and colorimetric determination of trace amounts (10^–4–10^–5%) of Cu, Al, Fe, Bi, Pb, Mn, Cd, Zn, Co, and M in platinum-rhodium (10%) alloys has been developed. The elements to be determined are retained on a column containing the strongly acidic cation-exchanger Amberlite IR-120, from dilute hydrochloric acid medium (p_H 1–1.5), while platinum and rhodium pass through in the form of anionic chloride complexes. The individual metals are eluted and concentrated and then separated by extraction and carrier precipitation. The metals are determined by means of sensitive colorimetrie methods with dithizone (Cu, Bi, Pb, Cd, Zn), eriochromecyanine R (Al), 2-nitroso-1-naphthol (Co),-furildioxime (Ni), 1-(2-pyridylazo)-2-naphthol (Mn), and thiocyanate (Fe). The error of the determination does not exceed 15%.

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Zusammenfassung Eine Trennungs- und Bestimmungsmethode für Spuren (10^–4 bis 10^–5%) von Cu, Al, Fe, Bi, Pb, Mn, Cd, Zn, Co und Ni in PIatm-Rhodium-(10%)-Legierungen wurde ausgearbeitet.Die angeführten Elemente werden mit Amberlit IR-120 aus der verd. salzsauren Lösung (p_H 1 bis 1,5) von Platin und Rhodium getrennt, die als Anionchloridkomplexe im Eluat bleiben. Die einzelnen Metalle werden nach Elution aus ihrer Lösung durch Extraktion bzw. Mitfällung getrennt und kolorimetrisch mit Dithizon (Cu, Bi, Pb, Cd, Zn), Eriochromcyanin R (Al), 2-Nitroso-1-naphthol (Co),-Furildioxim (Ni), 1-(2-Pyridylazo)-2-naphthol (Mn) und Rhodanid (Fo) bestimmt. Der Fehler beträgt weniger als 15%,