YS/T 1229.3-2018Methods for chemical analysis of crude nickel hydroxide - Part 3: Determination of copper, cobalt, manganese calcium, magnesium, zinc, iron, aluminum, lead, arsenic and cadmium contents - Inductively coupled plasma atomic emission spectrometry (English PDF)

3.12 Calcium standard stock solution: Weigh 2.500 g of calcium carbonate (standard,

pre-dried at 105 °C ~ 110 °C to constant weight, placed in a desiccator to cool to room

temperature) in a 250 mL beaker; add 20 mL of hydrochloric acid (3.2); cover with a

watch glass; heat to dissolve; boil to remove carbon dioxide; transfer to a 1000 mL

volumetric flask after cooling; use water to dilute it to the mark; mix well. 1 mL of this

solution contains 1 mg calcium.

3.13 Magnesium standard stock solution: Weigh 1.6582 g of magnesium oxide (WMgO

>= 99.95%, pre-calcined at 800 °C to constant weight, placed in a desiccator to cool to

room temperature) in a 250 mL beaker; add a small amount of water to moisten; add 10

mL of hydrochloric acid (3.2); cover with a watch glass; dissolve completely at low

temperature; transfer to a 1000 mL volumetric flask after cooling; use water to dilute it

to the mark; mix well. 1 mL of this solution contains 1 mg of magnesium.

3.14 Standard stock solution of zinc: Weigh 0.1000 g of metallic zinc (wZn >= 99.95%);

place it in a 400 mL beaker; add 20 mL of nitric acid (3.4); cover with a watch glass;

dissolve completely at low temperature; rinse the watch glass and the wall of the beaker

with water; heat and boil to expel nitrogen oxides. Remove and cool it; transfer to a

3.15 Standard stock solution of iron: Weigh 0.1430 g of ferric oxide (reference); place

it in a 400 mL beaker; add 15 mL of hydrochloric acid (3.1); cover with a watch glass;

heat at low temperature to dissolve completely; cool and transfer to a 1000 mL

volumetric flask; use water to dilute it to the mark; mix it. 1 mL of this solution contains

0.1 mg of iron.

3.16 Aluminum standard stock solution: Weigh 0.1000 g of aluminum (wAl >= 99.95%);

place in a 400 mL beaker; add 50 mL of hydrochloric acid (3.2); cover with a watch

glass; heat at low temperature to dissolve completely; cool and transfer to a 1000 mL

volumetric flask; use water to dilute it to the mark; mix it. 1 mL of this solution contains

0.1 mg aluminum.

3.17 Lead standard stock solution: Weigh 0.1000 g of lead (wPb >= 99.95%); place in a

3.18 Arsenic standard storage solution: Weigh 0.1320 g of arsenic trioxide (standard,

pre-dried at 100 °C ~ 105 °C for 1 h, placed in a dryer and cooled to room temperature)

in a 100 mL beaker; add 5 mL of sodium hydroxide solution (3.7); cover with a watch

glass; heat at low temperature until completely dissolved; add 5 mL of water and 2

drops of phenolphthalein ethanol solution (3.8); neutralize with hydrochloric acid (3.2)

until the red color just disappears; then add 2 mL in excess; transfer to a 1000 mL

volumetric flask; use water to dilute it to the mark; mix well. 1 mL of this solution

contains 0.1 mg of arsenic.

3.19 Cadmium standard stock solution: Weigh 0.1000 g of metallic cadmium (wCd >=

99.95%); place it in a 500 mL beaker; add 20 mL of nitric acid (3.3); cover with a watch

glass; dissolve completely at low temperature; cool and transfer to a 1000 mL

volumetric flask; use water to dilute it to the mark; mix it. 1 mL of this solution contains

0.1 mg of cadmium.

3.20 Copper, cobalt, manganese mixed standard solution: Pipette 20.00 mL of copper,

cobalt, manganese standard stock solutions (3.9 ~ 3.11), respectively, into a 200 mL

volumetric flask; add 10 mL of hydrochloric acid (3.2); use water to dilute it to the mark;

mix it. 1 mL of this solution contains 100 µg of copper, cobalt, manganese, respectively.

3.21 Mixed standard solution of calcium and magnesium: Pipette 20.00 mL of calcium

and magnesium standard stock solutions (3.12 and 3.13) into a 200 mL volumetric flask;

add 10 mL of hydrochloric acid (3.2); use water to dilute it to the mark; mix well. 1 mL

of this solution contains 100 µg of calcium and magnesium, respectively.

3.22 Mixed standard solution of copper, cobalt, manganese, calcium, magnesium:

Pipette 10.00 mL of copper, cobalt, manganese mixed standard solution (3.20) and

10.00 mL of calcium and magnesium mixed standard solution (3.21), into a 100 mL

volumetric flask; add 5 mL of hydrochloric acid (3.2); use water to dilute it to the mark;

mix well. 1 mL of this solution contains 10 µg of copper, cobalt, manganese, calcium,

magnesium, respectively.

3.23 Mixed standard solution of zinc, iron, aluminum: Pipette 20.00 mL of zinc, iron,

aluminum standard stock solutions (3.14 ~ 3.16) into a 200 mL volumetric flask; add

3.24 Mixed standard solution of lead and arsenic: Pipette 20.00 mL of lead and arsenic

standard stock solutions (3.17 and 3.18) into a 200 mL volumetric flask; add 10 mL of

hydrochloric acid (3.2); dilute to the mark with water; mix it. 1 mL of this solution

contains 10 µg of lead and arsenic, respectively.

3.25 Cadmium standard solution: Pipette 2.00 mL of cadmium standard stock solution

(3.19) into a 200 mL volumetric flask; add 10 mL of hydrochloric acid (3.2); use water

to dilute it to the mark; mix it. 1 mL of this solution contains 1 µg of cadmium.