Aluminium oxide primarily used for the production of aluminium — Determination of silica content — R...
The method is applicable to products having a silica content between 0.005 % (m/m) and 0.025 % (m/m) provided that the content of phosphorus pentoxide plus vanadium pentoxide does not exceed 0.02 % (m/m). The principle of the method is based on the formation of oxidized molybdosilicate (yellow) under well-defined conditions of acidity, concentration of reagents, temperature and time. Selective…
Sulphur for industrial use — Determination of arsenic content — Silver diethyldithiocarbamate photom...
Applicable to products having As contents equal or more than 0.5 mg/kg. In a well-ventilated cupboard, dissolution of a test portion in carbon tetrachloride. Oxidation of sulphur by bromine and nitric acid. Heating in a boiling water bath to eliminate the exess of bromine, carbon tetrachloride and nitric acid. The analysis is carried out according to ISO 2590. The replacement of some reagents…
Wrought steels — Macroscopic methods for assessing the content of non-metallic inclusions
Macroscopic methods deal with non-metallic inclusions visible to the naked eye or with the aid of a magnifying glass with a magnification of not more than X 10. Only inclusions equal to or greater than 1 mm long are taken into consideration. Covers the blue fracture test method, the step machined test method, the magnetic particle inspection method.
Essential oils — Estimation of primary and secondary free alcohols content by acetylation in pyridin...
The method consists in acetylating the hydroxyl groups containing compounds with a mixture of acetic anhydride and pyridine. The excess of acetic anhydride is hydrolized and the acetic acid formed is titrated with a potassium hydroxide solution. Primary and secondary alcoholes are acetylated completely by this method. Phenols, anthranilates and aldehydes are acetylated either completely or…
Phosphoric acid and sodium phosphates for industrial use (including foodstuffs) — Determination of f...
Applicable to products the F content of which is equal to or more than 0.5 mg/kg. Specifies the separation of the element from a test portion by steam distillation in a phosphoric acid medium. Formation of a blue-coloured complex with a combined reagent alizarin complexone/lanthanum nitrate in a buffered medium at the pH of 4.6. Addition of acetone to increase the stability of the complex and the…
Aluminium oxide primarily used for the production of aluminium — Determination of calcium content — ...
This method is applicable to products having Ca contents greater than 0,003 % (m/m). The principle consists in dissolution of a test portion by the influence of hydrochloric acid under pressure. Addition of sodium ions to promote and to stabilize the emission of calcium, and of lanthanum ions or triethanolamine to increase the sensitivity. Aspiration of the solution into an acetylene-dinitrogen…
Anhydrous hydrogen fluoride for industrial use — Determination of water content — Karl Fischer metho...
Applicable to products having a water content between 0.01 % (m/m) and 0.5 % (m/m). Is supplemented by ISO 3700 and intended for reference purposes. Bases on addition of a cooled test portion to cooled dry pyridine containing 5 % of anhydous hydrogen fluoride. The apparatus for measuring the test portion and titration and the measuring vessel are shon in figures. Subsequent electrometric…
Sodium fluoride primarily used for the production of aluminium — Determination of silica content — R...
Specifies a spectrophotometric method, using the reduced molybdosilicate, for determining the silica content of sodium fluoride. Applicable to products of which the phosphorus pentoxide content does not exceed 0,02 % (m/m).
