GB/T 23273.3-2009Methods for chemical analysis of cobalt oxatate - Part 3: Determination of arsenic content - Hydride generation-atomic fluorescence spectrometry (English PDF)

3.1

hydrochloride (rho1.19g/mL).

3.2

HCl (1 + 1).

Hydrochloride 3.3 (1 + 3).

Nitrate 3.4 (rho1.42g/mL).

3.5

nitric acid (1 + 1).

Thiourea 3.6 - ascorbic acid solution (100g/L). Weigh 10.0g of thiourea, was added 80mL of water was heated to about dissolved, cooled

10.0g ascorbic acid, dissolved diluted to 100mL, and mix using now.

3.7 solution of potassium borohydride (20g/L)

Weigh 2.0g of potassium borohydride is added 100mL sodium hydroxide solution (5g/L) were dissolved, and mix. use

When existing service.

3.8 cobalt matrix solution (cobalt-containing 16g/L)

Weigh 1.6000g metal cobalt (cobalt content >=99.98%, wherein the mass fraction of arsenic

< 0.0001%), was added 20mL of nitric acid (3.5) were dissolved, coolish, was added 10mL of hydrochloric acid (3.1) was dissolved to a small volume, and cooled to remove

At room temperature and transferred to 100mL volumetric flask, constant volume of water.

3.9 arsenic standard stock solution

Weigh 0.1320g trioxide (arsenic trioxide mass fraction >=99.9%, sulfuric acid in a dry beforehand

Is dried to constant weight) in 150mL beaker, 5mL sodium hydroxide solution (200g/L), cover the dish table, low dissolved, add 5mL

Water, 2 drops of phenolphthalein ethanol solution (1g/L), washed with hydrochloric acid (3.2) to the red and then disappear just excess 2mL, moved 1000mL volumetric flask

The constant volume of water. This solution 1mL containing 100µg arsenic.

3.10 arsenic standard solution

Pipette 10.00mL arsenic standard stock solution (3.9) in 1000mL volumetric flask, was added 20mL of hydrochloric acid (3.2), constant volume of water. This solution 1mL containing 1µg of arsenic.

3.11

argon (Ar>=99.99%).