Phosphoric acid for industrial use — Determination of sulphate content — Method by reduction and tit...
Applicable to products having sulphate contents equal to or more than 0.0005 % (m/m). Analysis by reduction of the sulphate to sulphide by a mixture of hydriodic acid and hypophosphorus acid. Absorption of the hydrogen sulphide evolved in a mixture of acetone and sodium hydroxide solution. Titration with a standard volumetric solution of mercury(II) acetate in the presence of dithizone as…
Sulphur for industrial use — Determination of total carbon content — Titrimetric method
Gives the potentiometric and visual methods als alternatives for the final titration. The principle consists in the combustion of the sulphur in a current of oxygen. Oxidation and fixation of the sulphur dioxide and trioxide gases in chromic and sulphuric acid solutions. Absorption of the carbon dioxide formed in a solution of barium hydroxide, followed by titration in the presence of…
Cryolite, natural and artificial — Determination of sodium content — Flame emission and atomic absor...
The methods are applicable as alternatives to products for which the molar ratio NaF/AlF3 is equal to about 3. The principle of the flame emission method consists in atomization of the test solution in a flame of oxygen/hydrogen and determination by measurement of the intensity of the radiation at 589 nm. The principle of the flame atomic absorption method is based on atomization in an air/…
Brown coals and lignites — Determination of the yields of tar, water, gas and coke residue by low te...
The sample is heated in an aluminium retort to a temperatur of 520 °C. The products of decomposition pass into a water-cooled receiver; the tar and water are condensed while gaseous products pass to atmosphere. The coke residue and the receiver and its contents are weighed. The mass of tar is obtained by difference to the mass of water determined by entrainment with toluene or xylene. A separate…
Coke — Determination of moisture in the analysis sample
A known mass of the coke is heated in air at a temperature between 190 and 210 °C and maintained at this temperature until constant in mass. The percentage moisture content is calculated from the loss in mass of the coke.
Glycerols for industrial use — Determination of arsenic content — Silver diethyldithiocarbamate phot...
The method is applicable tp products with a content greater than 0,1 mg/kg. It is applied to a test portion as it is, and to another identical portion with a known quantity of arsenic added. The principle consists in reduction of the arsenic by zinc in a hydrochloric acid medium, with the formation of arsine; absorption of the arsine in a solution of silver diethyldithiocarbamate in pyridine.…
Specifies a method of determination of ash, which gives an estimation of the content of mineral salts and other inorganic matter contained in pulp. It applies to all kinds of pulp.
Specifies the requirements and corresponding test methods. The pigments are suitable for use in paints and/or corrosion-inhibiting coatings. Three types of pigments are distinguished. In one typ only a lead content up 2 % maximum is alloqwed. Replaces ISO Recommendation R 1249-1970.
The Standard specifies the following characteristics of the oil. Appearance: Clear, mobile liquid. Colour: Pale yellow to orange-yellow. Odour: Characteristic with a strong note of citral. Relative density at 20/20 °C: 0,872 - 0,897. Refractive index at 20 °C: 1,4830 - 1,4890. Optical rotation at 20 °C: Range from - 3 to + 1 . Carbonyl compounds content, expressed as citral: Minimum 75 %.…
Gypsum plasters — Determination of water of crystallization content
Specifies a gravimetric method for the determination of the water of crystallization content of gypsum plasters. Describes also the principle, the apparatus, the preparation of the sample, the procedure, the expression of results, and the test report.
