GB/T 4325.2-2013Methods for chemical analysis of molybdenum - Part 2: Determination of cadmium content - Flame atomic absorption spectrometry (English PDF)

1 Scope

GB/T 4325 This section specifies the method for determination of molybdenum cadmium.

This section applies to molybdenum powder, molybdenum, molybdenum trioxide, ammonium molybdate Determination of cadmium content. Measurement range. 0.0002% to 0.100%.

2 Method summary

Sample was dissolved hydrogen peroxide. In nitric acid medium, the absorbance spectra measured at a wavelength of cadmium by flame atomic absorption at 228.8nm,

Computing element content. Join molybdenum substrate offset the impact of molybdenum.

3 Reagents

Unless otherwise indicated in the analysis using only recognized as analytical grade reagents and distilled or deionized water or equivalent purity.

4 Instrument

Atomic absorption spectrometer instrument, with a cadmium hollow cathode lamp.

Under optimum working conditions for those who can reach the following indicators can be used.

--- Characteristic concentration. the test solution and measurement matrix consistent solution, characteristic concentration of cadmium should not exceed 0.020mg/L;

--- Precision. measure up to 10 times the standard solution, the absorbance of the standard deviation should not exceed 1.5% of the average absorbance; the lowest

Concentration of standard solution (not "zero" concentration of the standard) measuring the absorbance of 10 times, the standard deviation should not exceed the maximum concentration standard

The average absorbance of standard solution of 0.5%;

--- Linear curve. the curve at a concentration divided into three segments, segment absorbance higher than the low segment of the absorbance difference, not less than

0.7.

5 Sample

Molybdenum should smash through the 0.75mm standard sieve.