GB/T 5059.9-2008Ferromolybdenum - Determination of sulfur content - The infrared absorption method and the combustion-iodate volumetric method (English PDF)

3.1 Principle

The sample is heated in a high frequency induction furnace combustion oxygen flow generated by the oxygen contained sulfur dioxide infrared analyzer to the measuring chamber dioxide

Sulfur absorbing specific wavelengths of infrared energy, which is proportional to the absorbed energy and the concentration of sulfur, based on the energy change detector receiving the measured amount of sulfur.

3.2 Reagents and materials

3.2.1

magnesium perchlorate, anhydrous, granular.

3.2.2

asbestos caustic soda, granular.

3.2.3

glass wool.

3.2.4

tungsten particles, sulfur content (mass fraction) of less than 0.0002%, particle size 0.8mm ~ 1.4mm.

3.2.5

tin particles, carbon content (mass fraction) of less than 0.0003%, particle size 0.4mm ~ 0.8mm.

3.2.6

Standard iron material/standard samples, purity (mass fraction) is greater than 99.8%, the sulfur content (mass fraction) of less than 0.002%, particle size

0.8mm ~ 1.68mm.

3.2.7

oxygen purity (volume fraction) is greater than 99.95%, if other levels of oxygen to obtain a low and consistent blank, can also be used.

3.2.8

power source gas, nitrogen or compressed air, the impurities (water and oil) content (mass fraction) of less than 0.5%.

3.2.9

ceramic crucible diameter × height 23mm × 23mm or 25mm × 25mm, and at more than 1200 °C high temperature furnace

The burning 4h or through an oxygen burning to blank the lowest value (1350 °C, not less than 3min).

3.2.10

crucible tongs.

3.3 instruments and equipment

3.3.1 Sulphur infrared absorption analyzer (sensitivity of 1.0 × 10-6)

Its apparatus shown in Figure 1.