BS ISO 12926:2012

This standard BS ISO 12926:2012 Aluminium fluoride for industrial use. Determination of trace elements. Wavelength dispersive X-ray fluorescence spectrometric method using pressed powder tablets is classified in these ICS categories:

• 71.100.10 Materials for aluminium production

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).

Table 1

Concentration range for aluminium fluoride (from fluorine) and trace elements

Compound or element	Symbol	Concentration range mass %
Aluminium fluoride	AlF3	86,5 to 95,75
Sodium	Na	0,05 to 0,25
Silicon	Si	0,001 to 0,14
Phosphorus	P	0,001 to 0,02
Sulfur	S	0,01 to 0,6
Calcium	Ca	0,001 to 0,10
Iron	Fe	0,005 to 0,05

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.