71.060.99 - Other inorganic chemicals

A test portion is evaporated at ambient temperature and the oil contained in the residue is extracted with carbon tetrachloride. The oil contained in the residue is determined either gravimetrically by evaporation of the organic solvent and weighing of the residue or by spectrometric measurement of the absorbance of the organic phase at a wavelength of approximately 3.42 m. The gravimetric method is applicable to products having an oil content equal to or greater than 10 mg/kg. The infra-red spe...view more

A test portion is evaporated in the presence of ethanediol and the water content of the residue is determined by the Karl Fischer method with direct electrometric measurement. The method is applicable to products having water contents equal to or greater than 50 mg/kg. For water contents greater than 1000 mg/kg it is preferable to dilute the evaporation residue with anhydrous methanol in accordance with ISO 4276 and titrate an aliquot portion of the diluted solution.

Specifies the apparatus and the procedure to be used. The procedure consists in removal of a sample into stainless steel cylinder, which has previously been cleaned, dried and evacuated and filling of the sampling cylinder with the stipulated quantity that is permissible with regard to safety. The filling shall never exceed 75 % of the capacity of the cylinder at ambient temperature.