Photometric Determination Of Silicon Research Articles

Cyclic injection photometric determination of silicon in oil products

A photometric procedure is developed for determining silicon in oil products involving the preliminary conversion of organic and inorganic silicon into silicate ions followed by their determination by the formation of reduced silicomolybdic heteropolyacid and cyclic injection analysis. The detection limit for silicon is 1 μg/g for a sample weight of 1 g.

Photometric determination of silicon in vanadium by MIBK extraction and molybdenum blue method

A photometric method for the determination of a microamount of silicon in vanadium metal is proposed. The method involves the extraction of silicomolybdic acid into methyl isobutyl ketone (MIBK) and the formation of molybdenum blue in the extract. By the method, more than 20 ppm of silicon in vanadium can be determined. The procedure is as follows. The sample is dissolved in nitric acid, evaporated to dryness, fused with sodium carbonate and dissolved with hydrochloric acid. An aliquot (V<50 mg, Si<50 μg) of the solution is taken and made up to 50 ml while keeping the acidity at 0.4M in hydrochloric acid. The solution is then treated with ammonium molybdate and oxalic acid, and silicomolybdic acid is extracted with MIBK. The extract is washed with hydrochloric acid and treated with stannous chloride solution. The absorbance is measured at 750 mμ using the solvent as a reference. The calibration curve should be prepared in the presence of the same amount of vanadium as that in sample solution.

Influence of temperature on the photometric determination of silicon in ferrous materials

A distinct influence of temperature has been indicated on the colour intensities of the reduced silicomolybdate solution confronted in the estimation of silicon in ferrous materials by the BISRA Methods of Analysis Committee procedure. This influence has been successfully overcome by employing ascorbic acid as a reducing agent in place of stannous chloride and hence the former reagent commends itself for adoption in the above procedure.

Influence of temperature on the photometric determination of silicon by the molybdenum blue methods

Some systematic studies have been carried out on the influence of temperature on the photometric determination of silicon by the molybdenum blue procedure. It has been shown that temperature exerts a distinct influence on the colour intensities involved in the different procedures and the extent of this influence depends largely on the nature of the acid medium and the reducing agent employed. Ascorbic acid has been successfully employed to overcome the influence of temperature.

Photometric determination of silicon in uranium metal with MIBK extraction and Molybdenum Blue

金属ウラン中の微量ケイ素の吸光光度定量法として,メチルイソブチルケトンを用いる新しい分析方法を研究し良好な結果を得た.試料を過酸化水素および塩酸に溶解し(酸可溶性ケイ素),または試料を硝酸に溶解後炭酸ナトリウムと融解したのち塩酸に溶解し(全ケイ素),塩酸濃度0.3～0.5Nとしてから,モリブデン酸アンモニウムを加えてケイモリブデン酸を生成させ,シュウ酸を添加したのちメチルイソブチルケトンでケイモリブデン酸を抽出分離する.アルコールおよび塩化第一スズを加えて均一溶液からモリブデン青を生成させ770mμまたは630mμの吸光度を測定してケイ素を定量する.試料0.2gを用い液量を20mlとして発色したとき,5～150ppmのケイ素を正確に定量することができた.金属ウラン中全ケイ素定量のための試料分解法について種々検討を加え,適切な試料融解法を考案した.

The photometric determination of silicon as α-silicomolybdic acid

A photometric method for the determination of silicon based on the yellow color of α-silicomolybdic acid is described. The pH must be kept within the range 3.0–3.7, and the equilibrium state is established by beating the solution. Since the color of this modification is remarkably stable and reproducible, a high degree of precision can be attained.

Photometric Determination of Silicon in Steel

Photometric Determination of Silicon in Steel

On the Photometric Determination of Silicon in Iron and Steel. II.

従来の方法は分析所要時間の短かい利点はあるが,フッ酸またはフッ化物を用いて多量の鉄イオンを錯化掩蔽するため,ガラス容器,とくに光度計の液槽が常用申に侵蝕されること・ケイモリブデン酸自体がフッ酸に対して不安定であること,ならびに酸に不溶性のケイ素化合物が全く考慮されていないこと等の欠陥がある。ところが多量の鉄イオンが共存する場合でもモリブデン青溶液の吸収が810～830mμ のもとで鉄イオンの吸収にくらべてずっと大きいので,フッ素イオンで錯化掩蔽しなくても鉄イオンによる補正を行えば十分目的を達することができ,また酸に不溶性のケイ素化合物は炭酸ナトリウムで溶融して定量することができる。このようにすれば上記欠陥をなくし,良好な結果の得られることを認めた。

The photometric determination of silicon in steels

The photometric determination of silicon in steels

Photometric Determination of Silicon in Ferrous, Ferromagnetic, Nickel, and Copper Alloys: A Molybdenum Blue Method

Photometric Determination of Silicon in Ferrous, Ferromagnetic, Nickel, and Copper Alloys: A Molybdenum Blue Method

The photometric determination of silicon in steels

AbstractA method for the determination of silicon in steels as the molybdenum blue complex is described. By the use of n number of alternative acid solvent mixtures, the method extends the range of steels which can be analysed by existing procedures. A new reducing agent, a mixture of ferrous sulphate and oxalic acid is used to give the molybdenum blue complex. The method is applicable to tungsten containing steels and to weld metal deposits.

Photometric determination of silicon in aluminium and its alloys

Photometric determination of silicon in aluminium and its alloys

Photometric determination of silicon in aluminium alloys: observations on Hadley's method

Photometric determination of silicon in aluminium alloys: observations on Hadley's method