GB/T 4324.20-2012Methods for chemical analysis of tungsten - Part 20: Determination of vanadium content - Inductively coupled plasma atomic emission spectrometry (English PDF)

3.1

Hydrogen peroxide (rho = 1.10g/mL).

Aqueous ammonia 3.2 (rho = 0.90g/mL), MOS level.

3.3

hydrochloric acid (rho = 1.19g/mL).

3.4

hydrochloric acid (119).

3.5 V standard stock solution. Weigh accurately 0.1785g vanadium pentoxide [w (V2O5) > 99.9%], sodium hydroxide solution was added 2mL (200g/L), heated until completely dissolved. Sulfuric acid was added 10mL (13) acidified dropwise a few drops of nitric acid (rho = 1.14g/mL) and evaporated to take

White smoke, remove it. Coolish, rinse the surface with a little water dish and cup wall, take fuming sulfuric acid again, the drive to make nitric acid. Coolish, transferred to 100mL volumetric flask

The diluted with water to volume, and mix. This solution 1mL containing 1mg vanadium.

3.6

vanadium standard solution A. Pipette 10.00mL vanadium standard stock solution (3.5), placed in 100mL flask, add 5mL hydrochloric acid (3.3), dilute to the mark and mix. This solution 1mL containing 100µg vanadium.

3.7 vanadium standard solution B

Pipette 10.00mL vanadium standard solution (3.6), placed in 100mL volumetric flask, was added 5mL hydrochloric acid (3.3),

Diluted with water to volume, and mix. This solution 1mL containing 10µg vanadium.

4.1

Inductively coupled plasma spectrometer with a resolution of < 0.006nm (200nm office).

4.2

Recommended vanadium analytical line wavelength 292.401nm.

The detection limit is 4.3 V 0.016µg/mL, measured limit of 0.080µg/mL.

The maximum concentration of a solution of 4.4 V continuous measurement of five times the relative standard deviation of the absolute intensity of the emitted light should be less than 1%.

4.5

linear curve, the correlation coefficient greater than 0.999.