GB/T 24164-2020Determination of chlorinated benzenes in dye products (English PDF)

Foreword

This Standard is drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 24164-2009 "Determination of the content of polychloriznated benzenes in dye products". Compared with GB/T 24164-2009, the main technical changes except editorial modifications are as follows.

- MODIFY the scope of the standard (see Clause 1 of this Standard, Clause 1 of the 2009 edition);

- DELETE the gas chromatography determination method (GC-ECD) (see Clause 4 of the 2009 edition);

- MODIFY the principle of the method (see Clause 3 of this Standard, Clause 3 of the 2009 edition);

- MODIFY the standard solution preparation method (see Clause 6 of this Standard, 4.3 of the 2009 edition);

- MODIFY the sample solution preparation method (see Clause 7 of this Standard, 4.5.1 of the 2009 edition);

- MODIFY the chromatographic analysis conditions (see 8.1 of this Standard, 4.5.2 of the 2009 version);

- MODIFY the requirements for determination of method accuracy (see 10.3 of this Standard, 5.2 of the 2009 edition);

- MODIFY the types of chlorinated benzenes (see Annex A of this Standard, Annex A of the 2009 version).

1 Scope

This Standard specifies the method for determining the residual amount of 12 kinds of chlorinated benzenes in dye products by gas chromatography-mass spectrometry (GC/MS).

This Standard applies to the determination of chlorinated benzenes in various types of dye products.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgement of limiting values

3 Principle of the method

In an ultrasonic bath, dichloromethane is used to extract chlorinated benzene in the sample, and gas chromatography-mass spectrometry (GC/MS) is used for separation and determination, and the peak area external standard method is used for quantification.

For the types of chlorinated benzene and reference parameters for determination, see Annex A.

4 Reagents or materials

4.1 Chlorinated benzene standards (see Annex A).

4.2 Dichloromethane, chromatographic grade.

5 Instruments and equipment

5.1 Gas chromatography-mass spectrometry (GC/MS). with EI source.

5.2 Chromatographic column. 50 % phenylmethylpolysiloxane stationary phase, such as DB-17MS, 30 m × 0.25 mm × 0.25µm or equivalent.

5.3 Analytical balance. accuracy of 0.01 mg.

5.4 Ultrasonic generator.

5.5 Extractor. stoppered tube, 10 mL.

5.6 Centrifuge. 4000 r/min.

5.7 Nitrogen sample concentrator.

6 Preparation of standard solution

7 Preparation of sample solution

10 Detection limit, precision and accuracy

11 Test report

The test report shall at least give the following information.

a) sample description;

b) serial number of this Standard;

c) test conditions;

d) method of use;

e) test results;

f) deviation from the standard;

g) test date.