GB/T 6684-2002Chemical reagent -- Hydrogen peroxide 30% (English PDF)

5.4 Chloride

Measure 18mL (20g) of sample [analytical reagent, chemical pure reagent take

9mL (10g)]. Dilute to 20mL. Determine according to GB/T 9729. The turbidity of the solution must not be greater than the standard comparison solution.

The preparation of the standard comparison solution takes the following amount of chloride standard solution:

Conduct the same processing with the sample at the same time.

5.5 Sulfate

Measure 9mL (10g) of sample [take 3.6mL (4g) of chemical pure reagent].

Dilute to 20mL. Add 0.5mL of hydrochloric acid solution (mass fraction is 20%) to acidize. Determine according to GB/T 9728. The turbidity of the solution must not be greater than the standard comparison solution.

The preparation of the standard comparison solution takes the following amount of sulfate standard solution:

Conduct the same processing with the sample at the same time.

5.6 Total nitrogen

Measure 4.5mL (5g) of sample [analytical reagent, chemical pure reagent take

1.8mL(2g)]. Place in a platinum dish. After the sample is completely decomposed, add 10mLof sulfuric acid solution (mass fraction is 5%).

Evaporate on water bath to 5mL. Move this solution to a branch tube distillation flask. Dilute to 140mL and determine according to GB/T 609. The solution shall not be yellower than the standard comparison solution.

The preparation of the standard comparison solution takes the following amount of nitrogen standard solution:

Guaranteed reagent, analytical reagent

Chemical pure reagent

Chemical pure reagent

Guaranteed reagent

Analytical reagent

The solution must not be redder than the standard comparison solution.

The preparation of the standard comparison solution takes the following amount of iron standard solution:

Conduct the same processing with the test solution that is completely decomposed at the same time.

5.10 Nickel

Measure 90mL (100g) of sample. Slowly inject into a platinum dish. After the sample is completely decomposed, evaporate dry on water bath. Add 0.5mL of hydrochloric acid solution (mass fraction is 20%) to dissolve the residue. Dilute to 25mL. Add 2mL of butadione oxime (nickel reagent) ethanol solution (10g/L),

2mL of sodium hydroxide solution (300g/L) and 1mL of potassium persulfate solution (50g/L). Shake well. The solution must not be redder than the standard comparison solution.

The preparation of standard comparison solution takes the standard solution that contains 0.002mg of nickel (Ni). Add 0.5mL of hydrochloric acid solution (mass fraction is 20%). Dilute to 25mL. Conduct the same processing with the same volume of test solution.

5.11 Copper

Determine according to GB/T 9723.

5.11.1 Instrument conditions

Light source: Copper hollow cathode lamp;

Wavelength: 324.7nm;

Flame: Acetylene-air.

5.11.2 Determination method

Measure 225mL (250g) of sample for guaranteed reagent. Measure 45mL (50g) of sample for analytical reagent. Measure 9mL (10g) of sample for chemical pure reagent. Slowly inject into a platinum dish. After the sample is completely decomposed, evaporate dry on water bath. Add 0.5mL of hydrochloric acid solution (mass fraction is 10%) to dissolve the residue. Dilute to 10mL.

Guaranteed reagent

Analytical reagent

Chemical pure reagent

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