Sodium fluoride primarily used for the production of aluminium — Determination of chlorides content ...
Applicable to products having a chlorides content, expressed as chlorine, of equal to or more than 0.005 % (m/m). The principle consists in precipitation, in the presence of boric acid, of chloride ions with silver nitrate. Comparison of the opalescence of the test solution with that of standard matching solutions using Nessler tubes against a black background. Turbidimetric evaluation of the…
Boric acid, boric oxide and disodium tetraborates for industrial use — Determination of chromium con...
Alkaline fusion of a test portion by sodium carbonate and subsequent neutralization by sulphuric acid. Measurement of the absorption of the complex formed by chromium and diphenylcarbazide at a wavelength of abour 540 nm after adding sodium azide for elimination of the colour caused by manganese.
diSodium tetraborates and crude sodium borates for industrial use — Determination of water content ...
Heating a test portion in a combustion tube at 250 0C, later at 500 0C. Passing through the liberated water carried by a flow of nitrogen into a tared absorption vessel filled with magnesium perchlorate. Weighing the absorption vessel and determination of the mass of water by difference.
Boric acid, boric oxide and disodium tetraborates for industrial use — Determination of chloride con...
The principle consists in titration of the cloride ions with standard volumetric mercury(II) nitrate solution in presence of diphenylcarbazone as indicator until the colour of the solution matches the mauve of the standard end-point matching solution.
Boric acid, boric oxide, disodium tetraborates, sodium perborates and crude borates for industrial u...
Preliminary reduction of the iron(III) by hydroxylammonium chloride, if required, suppression of the interference of tin by oxalic acid. Formation of the coloured iron(III)-2,2'-dipyridyl complex in a buffered medium. Photometric measurement of the coloured complex at a wavelength of about 522 nm.
Crude sodium borates for industrial use — Determination of iron soluble in alkaline medium — 2,2...
Applicable to products in which the content of soluble iron exceeds 2 mg/kg. The preparation of the test solution is carried out according to ISO 2217. Reduction of the iron(III), contained in the aliquot part of the solution, with hydroxylammonium chloride. Formation of the coloured complex between iron(II) and 2,2'-dipyridyl in buffered solution. Photometric measurement of the coloured…
Crude sodium borates for industrial use — Determination of aluminium soluble in alkaline medium — ED...
Applicable to products in which the content of soluble aluminium, expressed as Al2 O3 , exceeds 100 mg/kg. The preparation of the test solution is carried out according to ISO 2217. The reaction proceeds with the formation of the complex between EDTA and aluminium in an aliquot part of solution. Decomposition of the complex using sodium fluoride. Titration of the amount of liberated EDTA against…
Aqueous hydrofluoric acid for industrial use — Sampling and methods of test
Contains also titrimetric methods for determination of the total acidity, the hexafluorosilicic acid content and the non-volatile acids content and a method for calculating the hydrogen fluoric content. Specifies the scope and the field of application of these methods and declares the principle of the procedures. This second edition results from the incorporation of Addendum in the first one.…
Liquid chlorine for industrial use — Method of sampling (for determining only the volumetric chlorin...
The method is applicable when an agreement has previously been reached between the interested parties for the removal of two representative samples during filling of the tank-wagon at the manufacturer's premises. It cannot be applied when it is intended to determine the water content. The principle consists in checking that the equipment used is gas-tight; collection of the samples in steel…
