DANSK DSF/PREN ISO 18127 PDF

This dcoument specifies a method for the determination of fluoro-, chloro-, bromo- and iodo-organic compounds (AOF, AOCl, AOBr, AOI). Due to the high solubility of AgF in water the scope of ISO 9562 is restricted to Cl-, Br- and I-organic compounds (AOX, calculated as chlorine) because of the applied argentometric detection. The PN follows the proven AOX ISO 9562 method: adsorption of organohalogen compounds on activated carbon, oxidative combustion at 1000 °C with following alterations: constant water feed during combustion (hydropyrolysis), absorption of combustion gases in water, halide specific detection using ionchromatography. The method is applicable for the determination of 2 µg/l AOF, expressed as F 10 µg/l AOCl, expressed as Cl 1 µg/l AOBr, expressed as Br 1 µg/l AOI, expressed as I. Samples for determination of AOF are treated differently than samples for the determination of AOCl, AOBr and AOI. - Samples for determination of AOF are not acidified. The adsorption takes place under unchanged pH conditions. Washing is also performed with a neutral washing solution. - Samples for the determination of AOCl, AOBr and AOI are adjusted to a pH value 2 with nitric acid, the adsorption and washing take place in a nitric acid environment.