Zinc alloys — Determination of copper content — Electrolytic method
The method is applicable to zinc alloy Zn Al 4 Cu 1. It is suitable for the determination of copper contents between 0,5 and 3,5 %. This International Standard specifies principle, reagents, apparatus, sampling, procedure, expression of results and test report.
Sodium hydroxide for industrial use — Determination of carbonates content — Titrimetric method
Applicable to products having contents, expressed as CO2 , of more than 0.01 % (m/m). Relates to a procduct containing neither sulphides nor chlorates or only sulphides or only chlorates. Preliminary test by boiling an acidified test sample in the presence of methyl orange and with a lead acetate paper strip in the vapour. The sulphides blacken the paper and chlorates delolourize the methyl…
Analysis of soaps — Determination of glycerol content — Titrimetric method
The determination is carried out in the following way: Decomposition of the soap with sulphuric acid, and extraction of the fatty acids with light petroleum. Oxidation of the glycerol by periodic acid to formic acid and formaldehyde, and titration of the formic acid produced using a pH meter.
Wool — Determination of cysteic acid content of wool hydrolysates by paper electrophoresis and color...
Cysteic acid is one of the oxidation products of the amino acids cystine and cysteine. The cysteic acid content of raw wool is normally very low. It increases with photochemical degradation (weathering). Finishing processes such as bleaching or chlorination always result in an increase in cysteic acid. The severity of any kind of oxidation may be determined directly by quantitative determination…
Glycerine for industrial use — Determination of glycerol content — Titrimetric method
Applicable to the analysis of glycerines free from organic compounds other than glycerol having more than two hydroxyl goups on adjacent carbon atoms, such as sugars which can also give rise to formic acid and, for this reason, will interfere in the determination. The procedure begins with a cold oxidation of the glycerol by sodium periodate in a strongly acid medium, followed by titration of the…
Crude sodium borates for industrial use — Determination of total aluminium content — Titrimetric met...
Applicable to products having a total content up to 1 %. Is not applicable in the presence of zirconium or titanium. More than 0.006 % of iron will interfere in the determination. The principle bases on fusion of a test portion with sodium carbonate and extraction of the molten mass with hydrochloric acid. Formation of a complex by the addition of the disodium salt of ethylenediamintetra-ecetic…
Crude sodium borates for industrial use — Determination of total titanium content — Photometric meth...
Applicable to products having contents up to 0.1 % (m/m). The method specified is not applicable in the presence of vanadium or high silica content. Molybdenum and chromium also interfere. The analysis bases on fusion of a test portion with sodium corbonate, extraction of the cooled melt with suphuric acid and the addition of hydrogen peroxide. Photometric measurement of the yellow coloured…
