BS ISO 587:2020 pdf download – Coal and coke — Determination of chlorine using Eschka mixture.
2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 687, Solid mineral fuels — Coke — Determination of moisture in the general analysis test sample ISO 1170, Coal and coke — Calculation of analyses to different bases ISO 5068‑2, Brown coals and lignites — Determination of moisture content — Part 2: Indirect gravimetric method for moisture in the analysis sample ISO 11722, Solid mineral fuels — Hard coal — Determination of moisture in the general analysis test sample by drying in nitrogen ISO 13909‑4, Hard coal and coke — Mechanical sampling — Part 4: Coal — Preparation of test samples ISO 18283, Hard coal and coke — Manual sampling 3? Terms? and? definitions No terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https://www.iso.org/obp — IEC Electropedia: available at http://www.electropedia.org/ 4 Principle A known mass of sample is ignited in intimate contact with Eschka mixture in an oxidizing atmosphere to remove combustible matter and to convert the chlorine to alkaline chlorides. These are extracted with nitric acid or water and determined by either the Volhard or the Mohr method, or by potentiometric titration using an Ion Selective Electrode (ISE). 5 Reagents WARNING — Care should be exercised when handling reagents, many of which are toxic and corrosive. During analysis, unless otherwise stated, use only reagents of recognized analytical grade and only distilled water, or water of equivalent purity.
6.5 Flat plate, 6 mm thick, of silica or other suitable refractory material, which fits easily into the muffle furnace (6.3). 6.6 Potentiometric titration assembly, equipped with a chloride ion selective electrode and double junction reference electrode. 7 Preparation of the test sample The sample shall be the general analysis test sample, prepared to a nominal top size of 212 μm by the preparation procedures specified in ISO 13909‑4 or ISO 18283. The sample should be brought in moisture equilibrium with the laboratory atmosphere by exposure in a thin layer on a tray. Exposure time shall be kept to a minimum. The sample shall be thoroughly mixed for at least 1 min immediately before analysis, preferably by mechanical means. If the results are to be calculated other than on an “air‑dried” basis (see Clause 9), then, after weighing the test portion, determine the moisture content using a further portion of the test sample by the method specified in ISO 687, ISO 5068‑2 or ISO 11722.