1 Application scope
This standard specifies the cold atomic absorption spectrophotometry of mercury in stationary source emission.
This standard is applicable to the determination of mercury in stationary source emission.
For the purpose of this method, the detection limit is 0.025 g/25 ml of test sample solution. When the volume of sample is 10 L, the detection limit is 0.0025 mg/m3 and the determination limit is 0.01 mg/m3.
2 Normative references
The following documents contain provisions which, through reference in this standard, constitute provisions of this standard. For undated references, the latest edition applies.
GB/T 16157 The determination of particulates and sampling methods of gaseous pollutants emitted from exhaust gas of stationary source
HJ/T 373 Technical specifications of quality assurance and quality control for monitoring of stationary pollution source (Trial)
GB/T 6682 Water for analytical laboratory use—Specification and test methods
3 Method principle
Mercury in emission is absorbed by acidic potassium permanganate solution and oxidized to mercury ions, which are reduced to atomic mercury by stannous chloride. Mercury vapor is blown out from the solution and brought to mercury vapourmeter by carrier gas and determined with cold atomic absorption spectrophotometry.
4 Interference
Organic components such as benzene and acetone interfere with the determination.
5 Reagents and materials
Unless otherwise specified, analytical reagents that conform to relevant national standard shall be used for analysis. Experimental water, GB/T 6682, Level 2.
5.1 Concentrated hydrochloric acid: (HCl)=1.19 g/ml, guaranteed reagent.
5.2 Sulphuric acid: (H2SO4)=1.84 g/ml, guaranteed reagent.
5.3 Potassium permanganate (KMnO4): guaranteed reagent.
5.4 Mercury chloride (HgCl2): guaranteed reagent.
5.5 Sulphuric acid solution: (H2SO4)=10%.
Take 10.0 ml of sulphuric acid (5.2) and pour it into 100 ml of water.
Foreword iv
1 Application scope
2 Normative references
3 Method principle
4 Interference
5 Reagents and materials
6 Instruments and apparatus
7 Sample
8 Analytical procedures
9 Result calculation
10 Quality assurance and control