Aluminium fluoride for industrial use — Determination of fluorine content — Modified Willard-Winter ...
The principle of the method consists in fusion of a test portion with sodium carbonate. Separation of fluorine by distillation with sulphuric acid. Titration with thorium nitrate solution using sodium alizarinsulphonate-methylene blue as indicator. Alternatively, the thorium nitrate titration may be made using only sodium alizarinsulphonate; the end-point being spectrophotometrically determined…
Formaldehyde solutions for industrial use — Determination of iron content — 2,2'- Bipyridyl pho...
The specified method is applicable to the detection of Fe contents less than 0,0004 % (m/m). The principle consists in conversion of any iron present into the sulphate by evaporation to dryness in the presence of sulphuric acid, and reduction of iron (III) by means of hydroxylammonium chloride. Formation of a iron (II) 2,2'-bipyridyl complex. Photometric measurement of the coloured complex…
Formaldehyde solutions for industrial use — Determination of formaldehyde content
The specified method is applicable to HCHO contents between 25 5 and 45 %. The field of application may be extended by siutably modifying the mass of the test portion. The principle consists in the reaction of the test solution with a neutral sodium sulphite solution, and acidimetric titration of the liberated sodium hydroxide in presence of thymolphthalein as indicator.
Formaldehyde solutions for industrial use — Determination of methanol content
The results obtained by this method will include the methanol freed from combined forms. These are however not usually present at higher levels to effect the results. The principle consists in esterfication of the methanol present with formic acid using sulphuric acid as a catalyst. Distillation of the methyl formate into sodium hydroxide solution and back-titration of the excess sodium hydroxide…
Sulphuric acid and oleums for industrial use — Determination of oxides of nitrogen — 2,4- Xylenol sp...
The method ia applicable of oxide of nitrogen contents equal to or greater than 0,00002 % (m/m). The principle is based on oxidation of nitrous nitrogen to nitric nitrogen by potassium permanganate. Reaction of nitric nitrogen with 2,4-xylenol under specified conditions to form a nitrate derivate. Distillation of the nitrate derivate and absorption in sodium hydroxide solution. Spectrophotometric…
Chemical analysis of zinc alloys — Polarographic determination of lead and cadmium in zinc alloys co...
The method is applicable to the zinc alloys given in ISO 301. It is suitable for the determination of lead and cadmium contents over 0,0005 %. An application is permissible to zinc alloys not containing copper. Specifies principle, reagents, apparatus, sampling, procedure and test report.
Magnesium and its alloys — Determination of manganese in magnesium alloys containing zirconium, rare...
The method is applicable to the determination of manganese contents between 0,002 and 0,2 % (m/m). Specifies principle and procedure of the method, reagents, apparatus, sampling, expression of results and test report.
Liquid chlorine for industrial use — Determination of water content using an electrolytic analyser
Specifies a method for the determination of the volatile water, that which volatilizes at the same time as the liquid chlorine. It is intended for products with a moisture content of 0,001 % (m/m). The principle consists in contious absorption of the water in the gasified chlorine, flowing at a rate of 100 ml/min over phosphorus pentoxide applied in a thin layer on a glass rod. The glass rod…
Sodium hydrogen carbonate for industrial use — Determination of sodium carbonate — Titrimetric metho...
Applicable to products having content greater than 0,02 % (m/m). The principle consists in dissolution, in a specified volume of sodium chloride solution saturated at 20 °C, of the total sodium carbonate present in the test portion. Filtration of the insoluble matter which constitutes the major part of the sodium hydrogen carbonate. Titration, in an aliquot part of the filtrate, of the total…
