Determination of phosphorus in copper-phosphorus alloys,by GLC technique

Summary A simple, sensitive, accurate and rapid gas chromatographic method for the quantitative determination of phosphorus in copper-phosphorus alloys is described. The method is based on the chlorination of the sample with carbon tetrachloride in a sealed glass capsule at 550°C. The volatile products are introduced into the gas chromatograph after crushing the capsule in a special device. The method is very quick (ca. 20 min), involves simple manipulations and the error is about ±0.5%.     

Determination of phosphorus traces in platinum alloys by two-phase isotope exchange

The method of ZEMAN and KRATZER for the determination of phosphorus traces by means of two-phase isotope exchange was modified for the determination of phosphorus in pure platinum or pure platinum alloys. It was found that Pt, Rh, Ag, and As do not interfere with the determination. Among the elements usually present in platinum metal or platinum alloys, only gold interferes. It was removed by extraction from 7M HCl by MIBK and AmOAc. Hydrochloric acid also interferes but it can be removed by evaporation. The analytical procedure is given for the solution obtained by pressure decomposition of the sample (0.5 g) in a steel bomb with PTFE inlay. It is possible to determine >2 ppm P (approximate error −10%). Using a calibration dependence instead of the well known equation for isotope exchange, the content of P in the standard solution labelled with³²P need not be known.     

Determination of tin in titanium alloys

Tin-titanium alloys are becoming increasingly important; consequently a good method is needed for the determination of tin in this type of material. In this paper an accurate iodometric procedure is proposed for the determination. The sample is dissolved in sulfuric acid and the titanium oxidized with potassium permanganate. Tartaric acid is added and the tin precipitated with hydrogen, sulfide. The sulfide precipitate is dissolved in a mixture of sulfuric, perchloric and nitric acids and the solution evaporated to fumes of sulfuric acid. Water and hydrochloric acid are added, and the tin is reduced with lead and antimony trichloride and titrated with iodine. A study was made of the interfering elements that might be found in titanium alloys. The effect of antimony trichloride in reducing interference from copper was investigated. The method is recommended for titanium alloys containing 0.05 to 5.0 per cent. tin.     

Determination of nickel in gold-nickel alloys

An ion exchange separation based on the difference in adsorption from a chloride solution combined with an EDTA titration is suggested as a rapid and accurate method for the determination of nickel in nickel-gold alloys.     

Determination of niobium in zirconium-niobium alloys

A rapid control determination of niobium in 50% zirconium/50% niobium master-alloy is described; it is a direct spectrophotometric procedure, based on the reaction of niobium ions with hydrogen peroxide in concentrated sulphuric acid. The procedure is suitable for the examination of zirconium alloys containing niobium in the range 0.1 to about 60%. At least 1% of chromium, cobalt, copper, manganese, nickel or tantalum, does not interfere. Interference due to optical absorption by the peroxy-complexes of titanium, tungsten, molybdenum and vanadium is not significant in the determination of niobium above about 1%, provided that these metals are not in excess of about 0.5%, 0.25%, 0.1% and 0.02%, respectively. To compensate for optical absorption due to iron(III), a solution of the sample, not treated with peroxide, is used.     

Determination of cerium in ferrous alloys

A method for the determination of cerium in ferrous alloys is described. Cerium (with lead and bismuth) is separated from other elements by anion exchange in a medium consisting of 95% methanol and 5% 5 N nitric acid; cerium alone is tlien eluted with 90% methanol-10% 6 N hydrochloric acid and determined in the eluate by titration with EDTA to xylenol orange indicator. Application of the method to several steel samples was successful.     

Non-destructive determination of silicon in aluminium-silicon alloys by neutron activation analysis with a 227Ac-Be isotope neutron source

A method has been developed for the accurate determination of silicon in binary Al-Si alloys by instrumental neutron activation analysis with the aid of an ²²⁷Ac-Be isotope neutron source. Discs, weighing ca. 4 g, are irradiated at the maximum of the fast flux gradient in a rabbit lined internally with two layers of cadmium foil. Each irradiation is followed by an integral mode counting with discriminator baseline setting at 1400 keV. Standards consist of discs from high purity semiconductor silicon and aluminium (99.99%) metal. An iterative calculation procedure yields results with a relative precision from 0.6 to 8.1% for silicon contents between 13.5 and 0.5%. Triplicate analysis requires 21 min.     

Determination of niobium and tantalum in binary alloys and zirconium alloys

Recent developments in the metallurgy of niobium, tantalum and zirconium have necessitated provision of analytical procedures for determining niobium and tantalum in the presence of each other and in the presence of zirconium. For this purpose, absorptioinetric procedures based on the formation of yellow coloured complexes, between pyrogallol and niobium or tantalum, have been critically examined. Direct absorptiometric procedures are described, which are suitable for determining niobium or tantalum in the range 2 to 7%; when either of these metals exceeds 7%, differential absorptiometric procedures are recommended. Corrections must lie made for absorption due to the presence of other metals which form complexes with pyrogallol. In tlie determination of niobium or tantalum up to 5%, the precision of the method is about ±0.05%. About 12 determinations can be made in a day, by one analyst.     

Determination of phosphorus in phosphazenes and phosphines

An improved technique for the determination of phosphorus in organic phosphazenes and phosphines is described. An acid digestion using a mixture of fuming nitric, sulphuric and perchloric acids converts the organically bound phosphorus into orthophosphate. The orthophosphate is precipitated as magnesium ammonium phosphate, which is ignited to magnesium pyrophosphate. With this technique phosphorus was determined in several compounds. The results establish both good accuracy and precision for the method.     

ICP-AES测定硅锰中的磷

采用电感耦合等离子体-原子发射光谱法(ICP-AES)研究了硅锰合金中磷的测定,考察了试样的分解、分析谱线的选择、干扰元素的影响及精密度和准确度等影响的有关因素,其测定结果与国家标准方法一致.磷的分析谱线采用214.914 nm的测定结果最好;该方法的检出限为0.003％,回收率为96.9％～101.6 ％.     

Determination of phosphorus in polymers by INAA

An INAA technique employing beta spectrometry was developed for the determination of phosphorus in polymers. The (n,γ) reaction on phosphorus produces³²P, half-life 14.3 days, a pure beta emitter with end-point energy 1.71 MeV. Polymer samples in the form of powders, films and pellets are irradiated and then counted with a plastic scintillator. The beta spectrum is corrected for interferences (especially Sb, Zn and Br which are quantified by gamma spectrometry) and for energy loss in the thick sample. Samples must also be analyzed for S and Cl which cause nuclear interferences. With an irradiation time of 4 hours at a neutron flux of 5·10¹¹ n·cm^{−2 s −1}, decay time 10 days and counting time 10 minutes, the sensitivity is 520 counts/μg phosphorus and the detection limit is typically 2μg/g.     

Determination of copper in white-metal bearing alloys

A method is proposed for the determination of copper in white-metal bearing alloys by direct controlled-potential electrolysis with a tantalum cathode at -0.32 V vs. SCE in a sulphate/bisulphate buffered electrolyte (pH 2) with fluoroboric acid and sodium tartrate as masking agents. Only Bi(III) interferes. Any co-deposited Bi can be corrected for by its spectrophotometric determination with Semi-Xylenol Orange after preconcentration with La(III) as carrier, from an ammoniacal solution containing the redissolved deposit. Any residual Cu(II) in the electrolyte is determined by spectrophotometry with 2,9-dimethyl-1, 10-phenanthroline. The standard deviation of this method has been found to be 0.03 mg (n = 12) and its relative standard deviation from 0.03 to 0.17%. It has been successfully used for referee analysis and certification of standard reference materials.     

Determination of nitrogen,oxigen, fluorine,phosphorus, sulfur and chlorine in aluminium alloys by means of neutron activation

N, O, F, P, S, Cl can be mixed with aluminium during electrolysis, alloying operations and surface treatments. These elements allow changes in mechanical properties. We have adapted separation methods to neutron activation analysis of aluminium alloys down to the sub—ppm level. N, F, Cl, determinations need distillation. S and P separations are based on liquid extraction. O determination is carried out by instrumental method. Tracers and inactive carriers are used for separation study. Clearning of the surface is performed if necessary. 14 MeV neutron activation is applied to nitrogen, oxygen and fluorine determination. The sensitivity is about 200 imp/min/mg. Reactor neutron activation is performed for phosphorus, sulfur and chlorine analysis. The detection level is 0.1 μg/g. Interesting differences of N, O, F, and Cl contents are observed for Al−Zn or Al−Cu alloys in the range 0.1–10 μg/g.     

电感耦合等离子体发射光谱法测定植物油中的磷

用电感耦合等离子体发射光谱法(ICP-AES)测定了植物油中的磷.采用多谱线拟合技术(MSF)校正了铜对P213.617 nm和P214.914 nm光谱干扰.比较了活性炭炭化灰化法和微波消解法两种样品前处理方法对分析结果的影响.结果表明这两种前处理方法所得结果都能与国标磷钼蓝分光光度法的分析结果吻合,其中活性炭炭化灰化法的方法检出限(0.053 mg/kg)较微波消解法的方法检出限(0.42 mg/kg)更低,所以对低含量的磷的检测结果其相对误差及精密度更好.该法应用于植物油中磷的测定.     

Determination of phosphorus in organic compounds by NMR

Summary A method is described for the microdetermination of phosphorus by FTNMR in organic compounds containing transition metals. Approximately 10 mg of compound is digested for the determination and 2 mg Cr added as relaxation agent.

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Zusammenfassung Eine Mikromethode zur Bestimmung des Phosphors in organischen, Übergangsmetalle enthaltenden Verbindungen mit Hilfe der Fourier-Transform P³¹ kernmagnetischen Resonanz wurde beschrieben. Ungefähr 10 mg Substanz werden mit Schwefelsäure-Perchlorsäure aufgeschlossen und 2 mg Cr^III werden als Relaxans zugegeben.

     

Determination of phosphorus in waste water by EDXRF

Summary In a method developed for the determination of phosphorus in aqueous solutions, phosphorus was changed to the phosphate form, coprecipitated with hydrated iron(III) oxide, bound with activated charcoal and measured by EDXRF. The detection limit was 0.89 mg P/g activated charcoal. The method was used to determine the total phosphorus content of a waste water sample from a paper mill. Investigation of two sample destruction methods, dry ashing/HCl digestion and persulphate oxidation, showed the former to be more suitable for our purpose.     

Determination of indium and thallium in indium-thallium alloys

The thallium-indium alloys were dissolved in sulphuric acid (1 + 1). In this medium thallium remained in the univalent state and could be determined directly, without a separation, by an oxidation-reduction titration with potassium bromate. The indium was determined directly with an EDTA titration. Ascorbic acid was added to maintain the thallium in the univalent state, which did not interfere. Ascorbic acid also masked any interfering tervalent thallium by effectively reducing it to the univalent state. Sharp end-points were obtained for both titrations, which were carried out in the temperature range of 50-95 degrees . The method offers excellent precision and accuracy.     

Determination of phosphorus in coke by the oxygen-flask method

Recent developments in the oxygen-flask technique for determination of phosphorus in coke are described. The existing method was modified by use of the recently proposed potassium antimonyl tartrate catalyst for the ascorbic acid reduction of phosphomolybdate.