Ammonium hydrogen carbonate for industrial use (including foodstuffs) — Determination of arsenic con...
Applicable to products having As contents more than 0.2 mg/kg. The principle consists in reduction of the element to arsine in a solution of silver diethyldithiocarbamate in pyridine. Photometric measurement of the purplish- red colour produced by the colloidally dispersed silver, at the maximum of the absorption curve (wavelength approximately 540 nm).
Cryolite, natural and artificial — Conventional test for evaluation of free fluorides content
Applicable to products having contents of AlF3 of more than 0.15 % (m/m) or of NaF of more than 0.4 % (m/m). Covers sintering of a test portion with a known quantity of sodium fluoride in a muffle furnace at a temperature of (790 10) °C. Under these conditions, aluminium fluoride in excess of that required by the stoichiometric formula AlF3 .3NaF reacts to form cryolite; extraction of the ground…
Sodium fluoride for industrial use — Determination of carbonate content — Gravimetric method
Applicable to products having contents, expressed as Na2 CO3 , more than 0.02 % (m/m). Describes the release of the carbon dioxide from a test portion by acidification and heating. Entrainment of the carbon dioxide in a flow of air and absorption in weighed absorption tubes containing soda asbestos. Specifies the weighing of the absorption tubes to determine the quantity released.
Aluminium fluoride for industrial use — Determination of sodium content — Flame emission spectrophot...
Applicable to products having Na contents, expressed as Na2 O, of equal to or more than 0.05 % (m/m). The principle bases on fusion, at a controlled temperature, of a test portion with a mixture of lithium carbonate and boric oxide or with a mixture of lithium carbonate and lithium tetraborate in a platinum or platinum-gold alloy crucible. Extraction of the fused mass with hydeochloric acid…
Cryolite, natural and artificial, and aluminium fluoride for industrial use — Determination of sulph...
Applicable to products having a content, expressed as sulphur trioxide, equal to or more than 0.1 % (m/m). Bases on alkaline fusion of a test portion with a mixture of sodium carbonate and boric acid. Extraction of the fused mass with perchloric acid solution and precipitation of the sulphate ions with barium chloride in an acidified medium. Filtration on a fine-texture, ashless filter paper (…
Sulphuric acid and oleum for industrial use — Determination of total acidity, and calculation of fre...
Two cases are considered: sulphuric acid contents equal to or lower than 98 % (m/m) and sulphuric acid contents higher than 98 % (m/m). The principle is based on oxidation of a test portion with hydrogen peroxide and titration of the total acidity with a standard volumetric sodium hydroxide solution, in the presence of methyl red as indicator. - Replaces ISO Recommendation R 910-1968.
Method for the Determination of Particulate Mass Flows in Enclosed Gas Streams
1.1 Scope
1.1.1 This Standard describes test procedures and equipment which will permit accurate and reproducible determination of the particulate mass flows in enclosed gas streams. It is intended for use both before and after gas cleaning equipment (performance testing) or prior to emission of the gas stream into t he atmosphere. Note. It is recommended that the testing procedures in…
Urea for industrial use — Determination of biuret content — Flame atomic absorption and photometric ...
Applicable to products having contents of equal to or more than 0.05 % (m/m) (with flame atomic absorption) or 0.1 % (m/m) (with fotometric absorption). Covers the formation of a complex between biuret and copper(II) sulphate in alkaline medium. Fixation of this complex on an anion exchange resin. Elution of Cu first with a potassium nitrate solution and then with a nitric acid solution. Flame…
