Urea for industrial use — Determination of water content — Karl Fischer method
Specifies the manner in which this method is to be applied in a reaction of any water present in urea with a solution of iodine and sulphur dioxide in a mixture of pyridine and methanol (Karl Fischer reagent). This reagent is first standadized by titration with a precisely known mass of water. The end point of the reaction is read by the direct visual or direct electrometric method. The method…
Urea for industrial use — Determination of biuret content — Photometric method
Applicable to the determination in the presence of ammoniacal salts less than 15 mg in the aliquot amount taken for the determination. In the presence of quantities exceeding 15 mg the ammoniacal nitrogen shall be removed by a cation exchange resin because these salts interfere with the determination. The principle of the reaction consists in formation of a violet-red complex between allophanic…
1,1,1- Trichloroethane for industrial use — List of methods of test
Specifies the sampling, the determination of distillation characteristics, of the density at 20 0C, of residue on evaporation, of the water content, of the acidity and the measurement of colour in Hazen units. Has also been approved by the IUPAC.
Hexachlorobenzene for industrial use — List of methods of test
Specifies the sampling, the determination of the distillation characteristics subjected to the modifications appropriate for this product, of the water content, of the density at 20 0C and of the crystallizing point. Has also been approved by the IUPAC.
The first operation of the sampling procedure is inspection of the consignment. Before sampling the contents of the containers shall be homogenized. In the case of large containers five partial samples shall be withdrawn from each container at different specified depths. For each container the five partial samples shall be bulked and homogenizied. From this bulk three representative samples shall…
Aluminium oxide primarily used for the production of aluminium — Determination of boron content — Cu...
Applicable to products having boron oxide contents of more than 0.0006 % (m/m). With sufficiently sensitive apparatus, the lower limit of application may be extended to 0.00008 % (m/m). The test portion is dissolved in phosphoric acid. Separation of the boron by distillation as methyl borate. Formation of a red coloured complex between the boron and the curcumin reagent at pH 7.…
Surface active agents — Detergents — Anionic-active matter stable to acid hydrolysis — Determination...
The sample is hydrolyzed by refluxing under acid conditions. The non-hydrolyzable anionic-active matter is determined by the direct two-phase titration procedure describes in ISO 2271. This method is applicable to the determination of cyclic sulphonates in alkylphenol ether sulphates and of small amounts of sulphonates in sulphated fatty alcohols. The molar mass of the anionic matter must be…
Surface active agents — Detergents — Anionic-active matter hydrolyzable under alkaline conditions — ...
The determination is carried out as follows: Titration of an aliquiot portion of a sample solution with benzethonium chloride solution according to the direct two-phase titration procedure describes in ISO 2271. Hydrolysis by refluxing under alkaline conditions of a second aliquot portion of the sample solution. Titration of unhydrolyzed anionic-active matter with benzethonium chloride solution…
