YS/T 575.24-2009Methods for chemical analysis of aluminum ores. Part 24: Determination of carbon content and sulfur content. Infrared absorption method (English PDF)

3.1 Magnesium perchlorate: anhydrous; granular.

3.2 Alkali asbestos: granular.

3.3 Glass wool.

3.4 Tungsten particles: C <= 0.0008%, S <= 0.0005%; particle size: 0.4 mm ~ 0.8 mm.

3.5 Pure iron: purity is greater than 99.8%; carbon and sulfur contents are smaller than

0.002%; particle size: 0.8 mm ~ 1.68 mm.

3.6 Oxygen: purity is greater than 99.95%.

6.3 Calibration Test

6.3.1 In 3 ~ 5 porcelain crucibles (4.6), respectively weigh-take 0.2000 g ~ 0.4000 g of

corresponding standard samples. Cover 1.8 g of tungsten particles (3.4). Place them

on the crucible holder of a high-frequency burner; let in the oxygen stream and burn it.

Calibrate the low carbon and low sulfur channels of the instrument.

6.3.2 In 3 ~ 5 porcelain crucibles (4.6), respectively weigh-take 0.2 g of pure iron (3.5).

Weigh-take 0.1000 g of benchmark calcium carbonate (3.8); record its mass. Cover

0.2 g of pure iron (3.5) and 1.8 g of tungsten particles (3.4). Place them on the crucible

holder of a high-frequency burner; let in the oxygen stream and burn it. Calibrate the

high carbon channel of the instrument. Or, suitable standard samples with a high

carbon content may also be adopted to calibrate the high carbon channel.

6.3.3 In 3 ~ 5 porcelain crucibles (4.6), respectively weigh-take 0.2 g of pure iron (3.5).

Weigh-take 0.1000 g of potassium sulphate (3.9); record its mass. Cover 0,2 g of pure

iron (3.5) and 1.8 g of tungsten particles (3.4). Place them on the crucible holder of a

high-frequency burner; let in the oxygen stream and burn it. Calibrate the high sulfur

channel of the instrument. Or, suitable standard samples with a high sulfur content may

also be adopted to calibrate the high sulfur channel.

6.4 Times of Determination

Conduct three parallel determinations; take the average value.

6.5 Specimen

Weigh-take 0.1 g ~ 0.2 g of sample, accurate to 0.0001 g; record it as m.

6.6 Blank Test

Weigh-take 0.400 g of pure iron (3.5), place it in a crucible. Cover 1.8 g of tungsten

particles (3.4). Place on the crucible holder of a high-frequency burner; let in the

oxygen stream and burn it. Repeat enough times, till a low and relatively consistent

reading is obtained. Record at least three readings; calculate and record the average

blank value.

6.7 Sample Determination

In accordance with the requirements of the instrument, input the sample No.; place the

porcelain crucible on the balance. Add 0.20 g of pure iron (3.5); weigh-take 0.1000 g

of sample, accurate to 0.0001 g; record its mass. Cover 0.2 g of pure iron (3.5) and 1.8

g of tungsten particles (3.4). Place on the crucible holder; in accordance with the

instrument's instruction, initiate the analysis function and analyze the samples.

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