GB/T 29493.3-2023 Determination of harmful substances in textile dyeing and finishing auxiliaries - Part 3: Determination of organotins
WARNING - Persons using this document shall be familiar with normal laboratory practice. This document does not purport to address all of the safety problems. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.
1 Scope
This document describes a method for the determination of organotins in textile dyeing and finishing auxiliaries by gas chromatography-mass spectrometry (GC-MS).
This document is applicable to the determination of 18 kinds of organotins in textile dyeing and finishing auxiliaries (see Annex A).
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 6682 Water for analytical laboratory use - Specification and test methods
GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgment of limiting values
3 Terms and definitions
No terms and definitions are listed in this document.
4 Principle
The specimen is extracted by methanol-ethanol mixed solvent containing sodium diethyldithiocarbamate, and then reacted with sodium tetraethylborate at pH=4.5 to convert organotins into corresponding volatile ethylated derivatives, which are extracted with n-hexane, determined by gas chromatograph-mass spectrometer and quantified by internal standard method.
5 Reagents or materials
Unless otherwise specified, only recognized analytically pure reagent and Grade 2 water (specified in GB/T 6682) shall be used.
5.1 n-hexane, chromatographic grade.
5.2 Acetic acid, with a mass fraction of greater than or equal to 99.5%.
5.3 Methanol: chromatographic grade.
5.4 Ethanol, chromatographic grade.
5.5 Tetrahydrofuran, chromatographic grade.
5.6 Anhydrous sodium sulfate.
5.7 Sodium tetraethylborate (CAS No. 15523-24-7).
5.8 Sodium acetate trihydrate (CAS No. 6131-90-4).
5.9 Sodium diethyldithiocarbamate (CAS No. 148-18-5).
5.10 Organotin standard substances, with a purity (mass fraction) of greater than or equal to 99%, as shown in Table A.1.
5.11 Internal standard substances, with a purity (mass fraction) of greater than or equal to 99%, as shown in Table A.2.
5.12 Methanol-ethanol mixed solvent: mix methanol (5.3) and ethanol (5.4) well according to the volume ratio of 4:1.
5.13 Sodium diethyldithiocarbamate solution: weigh 0.4g (accurate to 0.01g) sodium diethyldithiocarbamate (5.9) and dissolve and dilute it with methanol-ethanol mixed solvent (5.12) to 1,000mL.
5.14 Acetate buffer solution: weigh 136.08g (accurate to 0.001g) sodium acetate trihydrate (5.8), dissolve it with 800mL water, adjust the pH value to 4.5 with acetic acid (5.2), and then dilute with water to 1,000L.
5.15 Derivatization reagent: weigh about 2g sodium tetraethylborate (5.7) in an inert environment and dissolve it with 10mL tetrahydrofuran (5.5). Tetrahydrofuran (5.5) shall be dehydrated with anhydrous sodium sulfate (5.6) before use, and the whole preparation process shall be protected by inert gas (such as nitrogen and argon). Do not expose residual sodium tetraethylborate (5.7) to air. Derivatization reagents may also be prepared by purchased sodium tetraethylborate having a fixed weight.
Foreword i
Introduction iii
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents or materials
6 Apparatus
7 Test steps
8 Test data processing
9 Lower determination limit, recovery rate and precision
10 Test report
Annex A (Normative) Basic information on organotins and internal standard substances tested in this document and information on the preparation of standard stock solutions
Annex B (Informative) Information on quantitative and qualitative ions of target organotins and internal standard substances
Annex C (Informative) GC-MS total ion chromatogram of ethylated derivatives of organotins and internal standard substances
