GB/T 24165-2020Determination of polychlorinated biphenyls in dye products (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This standard replaces GB/T 24165-2009 "Determination of Polychlorinated Biphenyls in Dyestuff Products". Compared with GB/T 24165-2009, except for The main technical changes in addition to the editorial modification are as follows.

---Modified the scope of application of the standard (see Chapter 1, Chapter 1 of the 2009 edition);

---Deleted the gas chromatography method (GC-ECD) (see Chapter 4 of the 2009 edition);

---Modified the principle of the method (see Chapter 3, Chapter 3 of the 2009 edition);

---Modified the standard solution preparation method (see Chapter 6, 4.3 of the 2009 edition);

---Modified the sample solution preparation method (see Chapter 7, 4.5.1 of the 2009 edition);

---Modified the chromatographic analysis conditions (see 8.1, 4.5.2 of the 2009 edition);

---Modified the determination requirements of method accuracy (see 10.3, 5.2 of the 2009 edition);

---Modified the types of PCBs (see Appendix A, Appendix A of the 2009 edition).

1 Scope

This standard specifies the method for the determination of 7 indicative PCB residues in dye products by gas chromatography-mass spectrometry (GC/MS) Principles, reagents or materials, instruments and equipment, standard solution preparation, sample solution preparation, analysis procedures, result calculation, detection limit, precision and Accuracy, and test report.

This standard applies to the determination of PCBs in various types of dye products.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this document.

For undated references, the latest version (including all amendments) applies to this document.

GB/T 8170-2008 Numerical rounding rules and the expression and determination of limit values

3 Principles of the method

In an ultrasonic bath, use dichloromethane to extract the PCBs in the sample, and use a solid phase extraction column (florisil SPE column) to extract After the eluate is concentrated and fixed to volume, it is separated and determined by gas chromatography-mass spectrometry (GC/MS). The peak area is external standard. Method quantitative.

See Appendix A for the types of PCBs and reference parameters for determination.

4 Reagents or materials

4.1 Standard PCBs (see Appendix A).

4.2 Dichloromethane, chromatographically pure.

4.3 N-hexane, chromatographically pure.

4.4 Mixed solvent of n-hexane-dichloromethane. the volume ratio of n-hexane and dichloromethane is 8.2.

4.5 Flori silica cartridge (SPE column). 1000mg, 6mL.

5 Equipment

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

5.2 Chromatographic column. 5% phenyl methyl polysiloxane stationary phase, 30m×0.25mm×0.25µm, or equivalent.

5.3 Analytical balance. accuracy 0.01mg.

5.4 Ultrasonic generator.

5.5 Extractor. 10mL tube with stopper.

5.6 Centrifuge. 4000r/min. […]