GB/T 33392-2016Leather and fur -- Chemical tests -- Determination of 4-aminoazobenzene derived from azo colorants (English PDF)

Foreword

This Standard was drafted as per the rules specified in GB/T 1.1-2009.

This Standard adopts the redrafting method to modify and use ISO 17234-2.2011

Leather – Chemical Tests for the Determination of Certain Azo Colorants in Dyed

Leathers – Part 2.Determination of 4-Aminoazobenzene.

Compared with ISO 17234-2.2011, this Standard made the structural adjustment, and

had the technical changes; Appendix D gives the list for the structural adjustment,

technical changes and its causes for reference.

This Standard was proposed by China National Light Industry Council.

This Standard shall be under the jurisdiction of National Technical Committee for

Standardization of Leather Industry (SAC/TC 252).

Drafting organizations of this Standard. State Center of Quality Supervision and Test

for Leather (Zhejiang); Haining Mengnu Group Co., Ltd.; Zhejiang Tongtianxing Group

Joint-Stock Co., Ltd.; Haining Sende Leather Co., Ltd.; Taizhou Lilin Leather Co., Ltd.;

Zhejiang Grammy Garments Co., Ltd.; and Zhejiang Institute of Standardization.

Chief drafting staffs of this Standard. Huang Xinxia, Xu Shouchun, Lan Li, Zhu

Miaofeng, Fu Wenrong, Yang Zhenwei, Guo Bin, Ma Hewei, and Wang Lingxia.

Leather and Fur –

Chemical Tests – Determination of 4-

Aminoazobenzene Derived from Azo Colorants

1 Scope

This Standard specifies the test method of gas chromatography-mass spectrometry

and high-performance liquid chromatography of 4-aminoazobenzene (CAS number.

60-09-3) that is decomposed from certain azo dyes in leather and fur and exists in free

form.

2 Normative References

The following documents are essential to the application of this document. For the

dated documents, only the versions with the dates indicated are applicable to this

document; for the undated documents, only the latest version (including all the

amendments) is applicable to this document.

GB/T 6682-2008 Water for Analytical Laboratory Use - Specification and Test

Methods (ISO 3696.1987, MOD)

3 Principle

After degreasing, the specimen is placed in an enclosed container; and is reduced by

sodium dithionite in an alkaline medium at a temperature of 40°C; and then the 4-

aminoazobenzene cleaved by reduction is extracted by tert-butyl methyl ether. After

purification, the extract liquor is determined by gas chromatography - mass

spectrometry (GC-MS) or high-performance liquid chromatography with diode array

detector (HPLC-DAD).

4 Reagents

Unless otherwise specified, only use reagents confirmed to be analytically-pure and

Grade-3 water specified in GB/T 6682-2008.

5 Apparatus

Gas chromatography-mass spectrometry (GC-MS), with an electron impact ion

source (EI).

Liquid chromatograph (HPLC), diode array detector (DAD).

6 Preparation of the Specimen

The leather is prepared in accordance with the provisions of QB/T 2716; while the fur

is prepared in accordance with the provisions of QB/T 1272.The sampling process

shall avoid the loss of hair.

The glue and attachments on the sample shall be removed as cleanly as possible.

7 Analysis Procedures

Add 9.0mL of sodium hydroxide solution (4.2) to the glass reactor; shake vigorously

after sealing; so that the sample is immersed in the liquid.

Capillary chromatographic column. DB-5ms, 30m×0.25mm×0.25µm; or equivalent.

Inlet temperature. 250°C.

8 Calculation of the Results

According to the GC-MS analysis results, the content of 4-aminoazobenzene in the

sample shall be calculated according to Formula (2).

9 Detection Limit and Recovery Rate

The detection limit in this method for 4-aminoazobenzene in the sample is 5mg/kg. The

recovery rate of the method shall be no less than 60%.

10 Presentation of the Results

The relative deviation of the two independent determination results shall be less than

10%. The content of 4-aminoazobenzene is expressed by the arithmetic mean of the

results of two parallel tests, in mg/kg, and the results are retained one digit after the

decimal point.

11 Test Report

The test report should include the following.

Appendix A

(Informative)

HPLC-DAD Chromatogram and Spectrogram

The HPLC-DAD chromatogram and spectrogram can refer to Figures A.1 and A.2,

respectively.

Appendix B

(Informative)

GC-MS Chromatogram and Mass-Spectrogram

The GC-MS chromatogram and mass-spectrogram can refer to Figures B.1~B.3.

Appendix C

(Informative)

Other Chromatographic Analysis Methods

For the detection of 4-aminoazobenzene in leather and fur samples, the following

chromatographic methods and conditions are for reference and use.

Appendix D

(Informative)

Technical Differences and Causes between this Standard and ISO

17234-2.2011

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