WARNING: The personnel using this standard shall have practical experiences in regular laboratory work. This standard does not point out all the possible safety problems. The users have responsibility to take proper safety and health measures and shall ensure to meet the requirements specified in national relevant regulations.
1 Scope
This standard specifies test methods for determination of the 4-aminoazabenzene decomposed from some azodyes in textile products by of gas chromatography-mass spectrogram detection method (GC /MSD) and high performance liquid chromatography method (HPLC/DAD).
This standard is applicable to various textile products after dyeing and printing.
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments (excluding amending error in the text) to, or revisions of, any of these publications do not be applied. However, the parties whose enter into agreement according to these specifications are encouraged to research whether the latest editions of these references are applied or not. For undated references, the latest edition of the normative document is applicable to these specifications.
GB/T 6682 "Water for analytical laboratory use - Specification and test methods" (GB/T 6682-2008, ISO 3696:1987, MOD)
GB/T 7592 "Textiles ― Determination of the banned azo colourants"
3 Principles
Samples in alkaline medium shall be reduced with sodium hydrosulfite; the decomposed 4-aminoazobenzene shall be extracted in proper liquid-liquid distribution method; carry out qualitative determination using the gas chromatograph (GC/MSD) with mass selective detector; if necessary, select high performance liquid chromatography - diode array detector (HPLC/DAD) to carry out the ratification of isomerides. Carry out the quantitation by gas chromatography - mass spectrogram internal standard method or high performance liquid chromatography external standard method.
4 Reagent
Except as otherwise herein provided, the used reagent shall be analytically pure and water shall be III grade water in accordance with those specified in GB/T 6682.
4.1 Sodium chloride
4.2 Tertiary butyl methyl ether (CAS No.: 1634-04-4).
Note: if without tertiary butyl methyl ether, fresh ethyl ether may be used to replace it. Preparation method of fresh ethyl ether: take 500mL ethyl ether and put it in 1000mL separatory funnel, add 100mL 5%ferrous sulfate solution, shake it violently, discard the water layer, put it in the all glass device to distill it and collect the distillate of 33.5℃~34.5℃.
4.3 Acetonitrile (HPLC Grade).
4.4 Sodium hydroxide solution, 20g/L.
4.5 Sodium hydrosulfite solution (200mg/mL): take sodium hydrosulfite (content of Na2S204 ≥ 85%), dissolve it with water and prepare the fresh solution.
4.6 Standard solution
1 Scope
2 Normative References
3 Principles
4 Reagent
5 Equipment and Instrument
6 Analytical Procedures
7 Result Calculation and Expression
8 Lower Limit, Recovery Rate and Precision of Determination
9 Test Report
Annex A (Informative) Reduction treatment method after specimen extraction
Annex B (Informative) Legend of gas chromatography -mass spectrometry
Annex C (Informative) Figure of high performance liquid chromatography
Annex D (Informative) Recovery rate
