Standards Development

Scope

This International Standard describes an X-ray fluorescence spectrometric (XRF) method for the determination of aluminium fluoride (AlF3) from the content of fluorine and the content of trace elements in the test specimen. The method does not determine the oxygen content. The calibration reference materials are not specified in this method.

The method is applicable to industrial-grade aluminium fluoride where the concentration range for aluminium fluoride and each trace element is within the concentration range given in Table 1. The validity and precision of test results for concentrations outside these ranges has not been determined (see Note).

Please see draft for Table 1 — Concentration range for aluminium fluoride (from fluorine) and trace elementsCompound or element Chemical composition The concentration range (g/kg) Fluoride F 57,00 to 66,00 Aluminium Al 30,00 to 35,00 Sodium Na 0,020 to 1,00 Silicon SiO2 0,010 to 0,50 Iron Fe2O3 0,010 to 0,15 Sulfur SO42- 0,05 to 1,00 Phosphorus P2O5 0,001 0 to 0,15

NOTE The determination of fluorine has an uncertainty due to mineralogical variation among origins of aluminium fluoride. Batches from different origins with the same fluorine contents can give different intensities when determined by this method and pressed tablet preparation does not eliminate this problem. An AlF3 sample of unusual mineralogical origin should be tested with an absolute method to verify that, when using this test method, the fluorine concentration range reported is valid.