Fluorochlorinated hydrocarbons for industrial use — Determination of acidity — Titrimetric method
Applicable to products the acidity of which is between 2 mol and 200 mol of univalent acid per kg. Two procedures are given: one is applicable to liquid products (R11, R113, etc.) and the other one to gaseous (R12, R22, etc.). The principle consists in extraction of the acids by water. Titration of the acids in the aqueous phase with standard volumetric sodium hydroxide solution in the presence…
Cryolite, natural and artificial, and aluminium fluoride for industrial use — Determination of water...
Applies to the simultaneous determination of the loss of mass at 550 °C which is the sum of the masses of water that has not undergone any reaction and of the hydrogen fluoride formed by pyrohydrolysis and the mass of water released at 550 °C determined by the Karl-Fischer Method (direct electrometric titration). Makes reference to ISO 760. The difference between these two determinations is due…
Sulphur for industrial use — Determination of acidity — Titrimetric method
Applicable to products having acidities, expressed as H2 SO4 , equal to or more than 0.01 % (m/m). Describes the extraction of acidic substances with a mixture of water and propan-2-ol (isopropyl alcohol). Titration of the extract with standard volumetric sodium hydroxide solution in the presence of phenolphthalein as indicator. The preparation of the sample from the laboratory sample is carried…
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…
