GB/T 14635-2020 English PDF (GBT14635-2020)

This Standard specifies the determination method of total rare earth content in the rare earth metals and their compounds. This Standard is applicable to the determination of the total rare earth content in rare earth metals and their compounds. This Standard contains two methods: Method-1 is oxalate gravimetric method, and Method-2 is EDTA titration method. Method-1 is applicable to the determination of the total rare earth content in single and mixed rare earth metals and their compounds; the determination range is shown in Table 1; it is not applicable to the determination of the total rare earth content in single and mixed rare earth metals and their compounds mainly based on erbium, thulium, ytterbium, and lutetium or the individual content of thorium and lead is greater than 0.1%. Method-2 is applicable to the determination of the total rare earth content in the single rare earth metals and mixed rare earth metals and their compounds mainly based on heavy rare earth holmium, erbium, thulium, ytterbium, and lutetium; the determination range is shown in Table 2; it is not applicable to the determination of the total rare earth content in the single rare earth with relative purity less than 99.5%, as well as in a single rare earth metal and its compounds with other impurity elements greater than 0.5%; it is also not applicable to the determination of the total rare earth content in materials with individual content of thorium, scandium, and zinc greater than 0.1%.