Behaviour of the dithiocarbamate complexes of arsenic, antimony, bismuth, mercury, lead, tin and selenium in methanol with a hydride generator

A study was carried out with a continuous hydride generator coupled to an atomic emission spectrometer with inductively-coupled plasma to determine whether hydrides of As, Bi, Pb, Sb, Sn and Se and mercury vapor could be generated in methanol solutions of their dithiocarbamate complexes. It was found that (with the exception of Pb) hydride generation with sufficient efficiency for simultaneous multi-element determination is achieved using 0.25% NaBH(4)-0.6 mol 1(-1) HCl as reaction medium. The detection limit was found to be 0.2 ng ml(-1) for As, 30 ng ml(-1) for Bi, 0.03 ng ml(-1) for Se, Sb and Sn.     

The atomic absorption spectrometric determination of arsenic,bismuth, lead,antimony, selenium and tin with a flame-heated silica t-tube after hydride generation

A modified technique with a simple T-tube for atomisation held above conventional atomic absorption burners is described. The absolute sensitivities are in the range 0.3–11 ng and the r.s.d. is usually below 5%. It is confirmed that prior oxidation of lead markedly increases the sensitivity.     

Grey cast iron reference material certified for antimony, arsenic, bismuth, and lead

Summary Almost 200 kg of grey cast iron, to which amounts of antimony, arsenic bismuth and lead were added, was prepared in the form of eighty bars. From these bars a number of disks (32 mm diameter, 10 mm thick) were cut. Homogeneity tests within disks and between disks cut from the same and from different bars showed that the inhomogeneity is less than 1.0 and 1.5% for antimony and lead, respectively. By means of electrothermal atomic absorption spectrometry, instrumental neutron activation analysis or radiochemical proton activation analysis the following 95% confidence intervals were certified: 263.5 ± 4.4 ppm for antimony, 347.1 ± 5.8 ppm for arsenic, 33.6 ± 0.8 ppm for bismuth and 296 ± 16 ppm for lead. The reference material is available for potential users.

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Referenzmaterial für graues Gußeisen, zertifiziert für Antimon, Arsen, Bismut und Blei

Zusammenfassung 200 kg graues Gußeisen mit Zusätzen von Sb, As, Bi und Pb wurden in Form von 80 Stangen hergestellt, die in Scheiben zerschnitten wurden (Durchmesser 32 mm, Dicke 10 mm). Homogenitätstests innerhalb und zwischen den Scheiben von derselben und von verschiedenen Stangen zeigten, daß die Inhomogenität für Sb bzw. Pb weniger als 1,0 bzw. 1.5% betrug. Durch elektrothermische AAS sowie durch Neutronenaktivierungsanalyse oder radiochemische Protonenaktivierungsanalyse wurden die folgenden Werte zertifiziert (95% Vertrauensintervall): 263,5 ± 4,4 ppm Sb, 347,1 ± 5,8 ppm As, 33,6 ± 0,8 ppm Bi und 296 ± 16 ppm Pb. Die Referenzmaterialien stehen Interessenten zur Verfügung.

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Senior Research Assoociate of the National Fund for Scientific Research (Belgium)     

Thermodynamic study of the system cadmium - zinc,cadmium - lead,cadmium - tin,bismuth - cadmium,tin - zinc,and lead - tin

Russian Chemical Bulletin -     

Electrothermal AAS determination of bismuth, antimony and tin in high-purity WO3

Summary Four methods for the bulk trace determination of Bi, Sb and Sn in WO₃ were developed and tested. In all cases, the final determination is carried out by graphite furnace atomic absorption spectrophotometry. The limits of detection range from 1 g/g for a very fast and simple method to 50 ng/g for a method comprising a trace-matrix separation by sorption and complexation on activated carbon powder loaded with TMDTC. A way of preparation of standard reference WO₃-samples doped with varying amounts of Bi, Sb and Sn traces is also described.     

oxidmetric titration of triphenyl derivatives of phosphorus,arsenic, antimony and bismuth with N-bromosuccinimide

A simple direct titration for milligram and microgram amounts of triphenylphosphorus, -arsenic, -antimony, and -bismuth is described. The methanolic sample solution, with a little water, hydrochloric acid and bromide added, is titrated with N-bromosuccinimide to a methyl red end-point. All four compounds were titrated in the same way with recoveries of 99–100% and relative standard deviations of 1–5% were obtained.     

Rapid method for the separation and determination of bismuth,antimony, and tin by controlled cathode electroanalysis

A study was made of the separation and determination of bismuth, antimony, and tin by electrochemical means, using controlled cathode potential. The effects of electrolyte composition, cathode potential, and temperature were investigated with respect to separations of the three metals and degree of recovery of each. Best results were obtained by use of an electrolyte containing sulfate and citrate. A procedure was devised which would serve for rapid analysis for bismuth, antimony and tin in the form of mixtures and alloys     

The atomic absorption determination of antimony,arsenic, bismuth, cadmium, lead, and tin in iron, copper,and zinc alloys with the graphite furnace

Antimony, arsenic, bismuth, cadmium, lead, and tin can be determined in metallurgical samples by flame atomic absorption spectrometry at levels of 0.005 wt%, but lower concentrations frequently necessitate preconcentration. The graphite furnace allows determination of these elements at concentrations 1–2 orders of magnitude lower than is possible with flame techniques. All six elements have detection limits at or below 1μg g⁻¹ in a variety of alloys. Calibration for antimony and load was done with standards containing the principal component of the alloy as a synthetic matrix. Bismuth, cadmium, and tin could be determined accurately only by the standard addition method. Arsenic could be determined in iron alloys with synthetic standards, but standard additions were required for copper alloys.     

Determination of tin, bismuth, antimony, indium, gallium and arsenic by solvent extraction cum atomic absorption spectrophotometry

A rapid atomic absorption spectrometric method for the determination of tin, antimony, bismuth, indium, gallium and arsenic in geological materials, steels and alloys is described. The samples are fused with sodium peroxide (for geological samples such as cassiterite and sulphides) or decomposed with sulphuric/hydrochloric acid mixture or by alkaline fusion (for silicates or bauxites) or by acid treatment (for steels, alloys and certain geological samples). The elements of interest are extracted as their iodides into methyl isobutyl ketone, stripped into aqueous solution by treatment with benzene, concentrated nitric acid and water, and determined by flame atomic-absorption spectrometry. Detailed study is made on stripping of the metals from organic phase as there no simple and rapid stripping procedures available. The method allows the determination of Sn, Sb, Bi and In down to 2 ppm and Ga down to 5 ppm. The relative standard deviations range up to 10% with an average of 2.5%. Apparent recoveries of these metals range from 90 to 110 with an average of 95% for Sb and 99% for others.     

Determination of copper,lead, tin and antimony by controlled-potential electrolysis : General method of analysis

A controlled-potential electrolysis method is described, by means of which it is possible to deposit copper, lead, tin and antimony from the same solution in successive stages. The behaviour of each metal during deposition as well as the best working conditions are discussed. The determinations are not affected by moderate amounts of Ni, Zn, Mn, Fe, Al     

Synthesis and evaluation of lead telluride/bismuth antimony telluride nanocomposites for thermoelectric applications

Heterogeneous nanocomposites of p-type bismuth antimony telluride (Bi_2−xSb_xTe₃) with lead telluride (PbTe) nanoinclusions have been prepared by an incipient wetness impregnation approach. The Seebeck coefficient, electrical resistivity, thermal conductivity and Hall coefficient were measured from 80 to 380 K in order to investigate the influence of PbTe nanoparticles on the thermoelectric performance of nanocomposites. The Seebeck coefficients and electrical resistivities of nanocomposites decrease with increasing PbTe nanoparticle concentration due to an increased hole concentration. The lattice thermal conductivity decreases with the addition of PbTe nanoparticles but the total thermal conductivity increases due to the increased electronic thermal conductivity. We conclude that the presence of nanosized PbTe in the bulk Bi_2−xSb_xTe₃ matrix results in a collateral doping effect, which dominates transport properties. This study underscores the need for immiscible systems to achieve the decreased thermal transport properties possible from nanostructuring without compromising the electronic properties.     

Reactions of diborane with organic derivatives of tin and lead

Diborane reacts with aryltin and aryllead compounds to give intermediates which on hydrolysis give arylboronic and arylborinic acids, and on oxidation give phenols.     

Exchange reactions between oxygen and sulphur derivatives of silicon, germanium, tin and lead

The exchange of oxygen functional groups (--- OR, --- O --- and --- OCOMe) and sulphur functional groups (--- SR, --- S --- ) between R₃M (M = Si, Ge, Sn and Pb) and R₂M (M = Si, Sn) shows, in general, the heavier Group IV element to prefer sulphur. This supports the phenomenological rationalisation that the softness of the organometallic residue increase with the atomic weight of M, though germanium probably resembles silicon in its behaviour far more that it does tin.     

Anion exchange separation of tin,antimony and tellurium

Tracer quantities of tin(IV), antimony(V) and tellurium(IV) are separated on Dowex-1 anion exchange resin in 0.1M oxalic acid. followed by 1M sulfuric acid.