Indirect atomic-absorption spectrophotometric determination of phosphorus in steel by use of the bismuth phosphomolybdate complex

An indirect method for determination of phosphorus by atomic-absorption spectrophotometry has been developed, based on formation of the bismuthophosphomolybdate complex and its extraction by methyl isobutyl ketone. Bismuth is determined in the extract and correlated with the phosphorus content. The method is applicable to different kinds of steel.     

Determination of phosphorus in steel with a stabilized-temperature graphite furnace and zeeman-corrected atomic absorption spectrometry

The determination of phosphorus in steel by graphite furnace a.a.s. is plagued by a spectral interference from the iron matrix which results in overcompensation when a continuum-source background corrector is used. Zeeman background correction using an alternating transverse magnetic field at the furnace eliminates this problem and allows a routine determination of phosphorus down to 0.002% in steel. Lanthanum is an effective matrix modifier for the phosphorus determination, but its enhancing effect depends largely upon the tube material used and the sample matrix. A 0.2% lanthanum solution was found to be optimum. The stabilized-temperature platform furnace concept allows an interference-free determination of phosphorus in steel, down to 0.002%, directly against aqueous standards. Atomizing the sample from a pyrolytic graphite platform in an uncoated graphite tube provides the optimum environment for a phosphorus determination.     

Polarographic determination of phosphorus

A method has been developed for the determination of phosphorus, as phosphate, by means of the catalytic polarographic wave for the reduction of hydrogen peroxide in the presence of Mo(VI). This reduction is combined with the previous formation and extraction of 12-molybdophosphoric acid. Depending on the extractant chosen, ethyl acetate or methyl isobutyl ketone, the determination limit is 2.3 or 3.1 mug l . respectively. The procedure has been applied to certified steel samples with good results.     

Determination of phosphorus in semiconductor grade silicon by neutron activation analysis

A method of determination of phosphorus in silicon has been elaborated. The separation of phosphorus is based on the extraction of phosphomolybdic complex in the presence of hold-back carriers of Ta and Au. Contamination factors for various impurities were determined. The lower limit of determination equals 3·10^?11 g P. Types of errors in the determination of concentration profiles are discussed.     

Study of the molecular absorption spectrometric determination of phosphorus in steel, nickel base alloys and zircaloy using the yellow phosphovanadomolybdate complex

Summary The molecular absorption spectrometric method using the yellow phosphovanadomolybdate complex,adopted as ISO-standard for determination of phosphorus in steel, has been optimized.High and varying blank values often reported in literature were found to be due to silicon interference. The silicon is released from the glass beaker during fuming with perchloric acid and the problem is avoided by either using teflon beakers or by adding hydrofluoric and boric acid after fuming.Interferences from elements present in the metal (arsenic, chromium, silicon and the refractory elements) were quantified and procedures are described for masking these interferences in order to make the method applicable to high-alloy steels, tool steels, nickel-base alloys and Zircaloys. Arsenic, hafnium, niobium, tantalum and tungsten cause the most severe interferences. Chromium, titanium and zirconium were found to have weak interferences whereas molybdenum and silicon did not interfere at all despite large amounts of precipitated oxides.Results reported by other authors that many old certified reference materials of low-and high-alloy steels have too high certified phosphorus values were confirmed with the described method as well as with the ICP-OES technique. However, the lower values were only found for alloys without Hf, Nb, Ta or W. Alloys containing these elements were often found to have higher phosphorus values, which reflects interferences not completely removed in the previous analyses of these alloys.

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Untersuchung der molekularabsorptions-spektrometrischen Phosphorbestimmung auf Grund des gelben Phosphovanadomolybdat-Komplex in Stahl, Nickellegierungen und ZircaloyPhosphorbestimmung in Referenzmaterialien

     

利用溶液状态的差别在大量钨存在下选择性测定微量钼

本文报道了在大量钨存在下选择性测定微量钼的方法。利用溶液状态的性质,研究加大钼、钨显色反应差别的条件,使钨失去了反应能力,而钼可选择性地显色。     

Polarographic Determination of Inorganic Phosphorus in Phytic Acid

Abstract

A method for the determination of inorganic phosphorus in phytic acid by polarography was developed. The mechanism of Mo/Sb/P polarographic behaviour has been studied. It is one of the most sensitive analytical methods of phosphorus at present. The limit of detection is 8x10^?9 g/ml. This method has been used in the determination of inorganic phosphorus in phytic acid and result is found satisfactory.     

Liquid extraction of molybdophosphoric and molybdoarsenic acids: application to the determination of phosphorus in the presence of arsenic

The radioisotopes phohphorus-32 and arsenic-74 have been used to study the extraction of molybdophosphoric and molybdoarsenic acids from aqueous solution with various organic solvents. A method is described for the gravivmetric determination of phosphorus in the presence of arsenic which makes use of solvent extraction with n-butyl acetate. The results obtained for the determination of phosphorus in various types of iron and steel are described.     

Substoichiometric determination of tungsten by neutron activation analysis

A method for the substoichiometric determination of tungsten by thermal neutron activation analysis has been developed based on the selective extraction of the tungsten dithiol complex into amyl acetate. The method is simple, rapid and accurate. It has been used in the determination of tungsten in alloy steel, meteorites and biological standard kale.     

Indirect atomic-absorption spectrophotometric determination of phosphorus after flotation as the ion-pair of molybdophosphate with bis[2-(5-chloro-2-pyridylazo)-5-diethylaminophenolato]cobalt(III)

An atomic-absorption spectrophotometric method has been developed for the indirect determination of phosphorus. The calibration graph is linear over the range 0.025-0.2 mug of phosphorus. The relative standard deviation is 1.3% for 0.2 mug of phosphorus (6 replicates). The method has been applied to the determination of phosphate in natural water samples. The enhancement effect of acetone on the determination is discussed.     

Spectrophotometric determination of cobalt with nitrosochromotropic acid

A sensitive spectrophotometric method for the determination of trace amounts of cobalt based on the complex formation with nitrosochromotropic acid in ammoniacal medium is described. After its extraction as thiocyanate complex into isobutylmethyl ketone, cobalt is stripped into nitrosochromotropic acid in ammonia buffer. The method has been applied to the determination of cobalt in mild steel, ferrous alloys and multivitamin preparations.     

Derivative activation analysis of phosphorus at ppb levels in water samples

A neutron activation analysis procedure has been developed for the indirect determination of phosphorus as orthophosphate at ppb levels, via the formation of antimonyl phosphomolybdic acid. The complex is adsorbed on Sephadex G-25 resin and the antimony is estimated through NAA, allowing the determination of phosphorus. The procedure provides an easy method to adopt for the routine determination of phosphorus at 10 ng ml^–1 levels with good precision, in water samples.     

The determination of boron in ferrous and non-ferrous alloys by neutron transmission

A method has been developed for the determination of 0.1 to over 20% of boron in aluminium-and complex ferro-alloys, based on the neutron-absorbing properties of the¹⁰B nucleus. It has also been applied to stainless steel. The determination is fully automatic and results are conveniently processed by computer.     

多元光谱拟合-电感耦合等离子体原子发射光谱法测定钢铁中的磷

研究了采用多元光谱拟合(MSF)功能ICP-AES法测定钢铁中磷的方法。采用MSF法扣除光谱干扰,选择波长为213.617nm的谱线作为磷的分析线,样品用硝酸(1+5)和浓盐酸溶解后可用ICP-AES直接测定。考察了仪器工作参数对测定结果的影响,确定了最佳工作条件:观测高度为13mm,雾化气流速为0.7L/min,射频功率为1300W。实验结果表明,方法的线性范围为0.05～100mg/L,线性相关系数为0.9998,检出限为0.0411mg/L,样品测定结果的相对标准偏差(RSD)为1.8%,加标回收率为96.1～100.8%。方法准确、快速,具有良好的精密度和准确度,可用于钢铁中磷的测定。     

Spectrophotometric determination of cobalt(II) with 2-(3′-sulfobenzoyl)pyridine benzoylhydrazone

A simple method has been described for the Spectrophotometric determination of cobalt(II) with 2-(3′-sulfobenzoyl)pyridine benzoylhydrazone (SBPBH). In aqueous solution, cobalt(II) reacts with SBPBH to form a yellow complex, which is not destroyed even by the addition of 3.8 M perchloric acid. The absorption maximum of the complex in 1.5 M perchloric acid medium was found to be 400 nm; the molar absorptivity was 2.17 × 10⁴ liters mol⁻¹ cm⁻¹. The proposed method is fairly selective and has been applied to the determination of cobalt in standard alloy steel samples.     

Synergic extraction and spectrophotometric determination of titanium(IV)

A method has been developed for the synergic extraction and spectrophotometric determination of Ti(IV) with N-hydroxy-NN'-diphenylbenzamidine and thiocyanate. The yellow ternary complex, extracted into chloroform from dilute sulphuric acid medium (pH = 1.5+/-0.1), has maximum absorbance at 390 nm (molar absorptivity 1.3 x 1O(4) 1.mole(-1). cm(-1)). The method is free from interference from a large number of foreign ions and is recommended for the determination of titanium in steel.     

测定痕量磷的激光热透镜光谱法--钼蓝法与孔雀绿法的比较

采用激光热透镜光谱法（LTLS）,分别以孔雀绿－磷钼杂多酸缔合物法和磷钼蓝法对痕量磷进行了测定;探讨了测定条件的影响,分析比较了两种测定方法,结果表明,钼蓝法的线性范围较宽,孔雀绿法的灵敏度较高,选择性较好,将孔雀绿LTLS法应用于河水、自来水和土壤样品中痕量磷的分析测定,取得了满意的效果。     

Spectrophotometric Determination of Trace Amounts of Molybdenum in Steel and Pure Iron with a New Chromogenic Reagent Dimethoxyhydroxyphenylflurone

ABSTRACT

A simple method for the direct determination of trace molybdenum in low alloy steel and pure iron with selectivity and sensitivity is reported. In the presence of TritonX-100 and sulphuric-phosphoric acid medium, a new chromogenic reagent dimethoxyhydroxyphenyl-flurone (DMHPF) forms a red complex with molybdenum(VI). The molar absorptivity is obeyed from the range of 0? 8 μg/25 ml for molybdenum(VI). Most of metal ions and 35000-fold amounts of iron do not interfere with the determination of molybdenum. The proposed method has been successfully used for the determination of trace amounts of molybdenum in steel and pure iron specimens.     

Determination of phosphorus in hypereutectic aluminium-silicon alloys

A reproducible method is described for determination of small amounts of phosphorus (from 0.0005% to 0.02%) in hypereutectic aluminium-silicon complex alloys. The method permits the separate determination of phosphorus in acid-soluble and acid-insoluble fractions. Phosphomolybdate is extracted with n-butanol-chloroform solvent mixture and back-extracted with a btannous chloride reducing solution. The phosphorus content of a sample cut into small pieces decreases during storage; loss of phosphorus is negligible on acid dissolution under oxidizing conditions.     

Absorptiometrische Bestimmung von Phosphor im Stahl

Zusammenfassung Der von Lueck u. Bolz beschriebenen Methode zur Bestimmung von Phosphor in unlegiertem Stahl wird eine Form gegeben, die es gestattet, Phosphor in allen Stählen zu bestimmen. Nach dem Lösen der Probe werden Silicium, Chrom und Arsen durch Destillation entfernt, Phosphor wird als Molybdatkomplex extrahiert und über die Molybdänblaufärbung photometrisch bestimmt. Störungen und Reproduzierbarkeit werden eingehend untersucht.

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Summary The determination of phosphorus in plain carbon steel according to Lueck and Bolz has been modified for application to all kinds of steel. After dissolution of the sample silicium, chromium, and arsenic are removed by distillation, phosphorus is extracted as molybdate complex and determined photometrically as molybdenum blue. Interferences and reproducibility are investigated thoroughly.