Determination of banned azo colourants in dyed textiles and leather products for import and export—Part 1:High performance liquid chromatography method
1 Scope
This part of SN/T1045 specifies the liquid chromatography test method to determine the content of 23 banned aromatic amines (see Annex A) in dyed textiles and leather products.
This part is applicable to the testing of 23 banned aromatic amines in dyed textiles (including cotton, linen, silk, wool, chemical fiber, etc.) and dyed leather products for import and export.
2 Normative References
The following standards contain provisions which, through reference in this part of SN/T1045, constitute provisions of this part. For dated references, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, parties to agreements based on this part are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest editions apply to this part.
GB/T 6682 Water for Analytical Laboratory Use - Specification and Test Methods
SN/T 1045.2 Determination of Banned Azo Colourants in Dyed Textiles and Leather Products for Import and Export Part 2: Gas Chromatography/Mass Spectrometry Method
3 Theory
In the citrate buffer (pH = 6.0), the azo colourants in the specimen are reduced to the corresponding aromatic amine intermediate by sodium hydrosulfite The aromatic amine in the aqueous solution is extracted with a methyl tert butyl ether - dichloromethane mixed solvent. The aromatic amine in the extract is acidified to a salt by hydrochloric acid and sodium silicotungstate (Na8SiW11O39•nH2O) solution, and then concentrated, with the residue washed by an organic solvent. After alkalization, the free aromatic amine is extracted by methyl tert butyl ether. After the organic layer is blown dry, the residue is dissolved with methanol, and the banned aromatic amine compound is determined by a high performance liquid chromatography/diode array detector.
4 Reagents
Foreword i
1 Scope
2 Normative References
3 Theory
5 Instruments and Apparatus
6 Analytical Procedures
7 Minimum Detection Limit
8 Precision
Annex A (Normative) Chemical Names and CAS RN of 23 Kinds of Banned Aromatic Amines
Annex B (Informative) Infrared and Ultraviolet Spectrograms of Sodium Silicotungstate (Na8SiW11O39•nH2O)
Annex C (Normative) Polyester Specimen Pretreatment Method
Annex D (Informative) Liquid Chromatogram of Aromatic Amine Standards
Annex E (Informative) Ultraviolet Spectrogram of Aromatic Amines
