Acid-grade fluorspar — Determination of available fluorine content — Potentiometric method after dis...
Specifies a potentiometric method using a fluoride-ion sensitive electrode. After destillation of fluorine from the test portion in the presence of perchloric acid the distillate shall be titrated with lanthane nitrate solution. Applicable to products having a calcium fluoride content greater than 90 %.
Fruits, vegetables and derived products — Determination of sorbic acid content
The method consists in homogenizing the product, followed by quantitative entraining, by steam, of the acid present in a test portion, determination of the acid in the destillate obtained, either by spectrophotometry in the ultra-violet range (technique A) or by measuring by photocolorimetry or by spectrophotometry the pink colour obtained after oxidation by chromic acid and then treatment with…
Condensed phosphates for industrial use (including foodstuffs) — Determination of arsenic content — ...
Applicable to products having As content equal or more than 0.2 mg/kg. Dissolution of a test portion, acidification with hydrochloric acid solution and oxidation with potassium bromide-bromate solution, followed by hydrolysis. Determination in accordance with the general method in ISO 2590, clause 3. Has also been approved by the IUPAC.
Hardmetals — Determination of titanium — Photometric peroxide method
The method is applicable to carbide and binder metal powder mixtures, free of lubricant, and all grades of presintered or sintered hardmetals, with a titanium content exceeding 0,2 % (m/m). Specifies principle, interfering elements, reagents, apparatus, sample preparation, procedure, elimination of interferences, preparation of the calibration curve, expression of results and test report.
Metallic powders — Determination of acid insoluble content in iron, copper, tin and bronze powders
The insoluble matter is generally considered to be acid-insoluble silica and silicates, carbides, alumina, and clays. The methods are applicable to lubricant-free powders. ISO 4496 specifies apparatus and reagents, sampling, procedure, expression of results and test report.
Sulphuric acid for industrial use — Determination of arsenic content — Silver diethyldithiocarbamate...
Describes a method applicable to products having aresenic contents equal to or greater than 0,1 mg/kg. As far as principle, the reagents and apparatus to be used are concerned, reference is made to ISO 2590, with some modifications added. For example, the reduction of arsenic by zinc is carried out in sulphuric acid medium. Provides information on the expression of results and the particulars to…
