GB/T 4325.16-2013Methods for chemical analysis of molybdenum - Part 16: Determination of potassium content - Flame atomic absorption spectrometry (English PDF)

1 Scope

GB/T 4325 provisions of this part of the molybdenum powder, molybdenum, molybdenum trioxide and potassium determination of the amount of ammonium molybdate.

This section applies to powder, molybdenum, molybdenum trioxide and molybdenum determination of potassium content of ammonium molybdate. Measurement range. 0.0010% to 0.150%.

2 Method summary

Sample decomposition of hydrogen peroxide, cesium chloride as deionization agent, air - acetylene flame atomic absorption spectrometer, the wavelength 766.5nm

At measuring the absorbance of potassium in the matrix matching conditions, calculate the amount of potassium.

3 Reagents

Unless otherwise indicated, this part of the reagents used are in line with national standards or industry standards for gifted class pure reagents, the double-distilled water

Or equivalent purity, shall comply with GB/T 6682's.

4 Instrument

Atomic absorption spectrometer, with a potassium hollow cathode lamp.

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

--- Characteristic concentration. in the solution was measured and consistent substrate solution, wherein the concentration of potassium is not more than 0.01µg/mL;

--- Precision. measure up to 10 times the standard solution, the absorbance of the standard deviation should not exceed the average absorbance of 1.0%; the lowest

Concentration of standard solution (not "zero concentration" standard solution) 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 according to concentration, is divided into five sections, the difference between the absorbance of the absorbance difference between the highest and the lowest segment of the segment

Ratio of not less than 0.7.

5 Sample

Molybdenum should smash through the 0.75mm standard sieve.