GB/T 6324.11-2021Test method of organic chemical products—Part 11: Determination of trace arsenic in liquid products—Atomic fluorescence spectrometric method (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document is part 11 of GB/T 6324 "Test Methods for Organic Chemical Products". GB/T 6324 has released the following parts.

---Part 1: Water miscibility test of liquid organic chemical products;

---Part 2: Determination of the dry residue after evaporation of the volatile organic liquid on the water bath;

---Part 3: Determination of reduced potassium permanganate substances;

---Part 4: Determination of trace sulfur in organic liquid chemical products by microcoulometric method;

---Part 5: Determination of carbonyl compound content in organic chemical products;

---Part 6: Determination of the chromaticity of liquids, tristimulus value colorimetry;

---Part 7: Determination of Melt Color;

---Part 8: Determination of Moisture in Liquid Products by Karl Fischer Coulometric Method;

---Part 9: Determination of chlorine;

---Part 10: Determination of trace sulfur in organic liquid chemical products by ultraviolet fluorescence method;

---Part 11: Determination of Trace Arsenic in Liquid Chemical Products Atomic Fluorescence Method.

Introduction

The purpose of GB/T 6324 is to establish a unified test method for organic chemical products involving more inspection items.

The development and maturity of the inspection project needs to be updated and improved. This series of standards has established the following eleven parts.

---Part 1: Water miscibility test of liquid organic chemical products;

---Part 2: Determination of the dry residue after evaporation of the volatile organic liquid on the water bath;

---Part 3: Determination of reduced potassium permanganate substances;

---Part 4: Determination of trace sulfur in organic liquid chemical products by microcoulometric method;

---Part 5: Determination of carbonyl compound content in organic chemical products;

---Part 6: Determination of the chromaticity of liquids, tristimulus value colorimetry;

---Part 7: Determination of Melt Color;

---Part 8: Determination of Moisture in Liquid Products by Karl Fischer Coulometric Method;

---Part 9: Determination of chlorine;

---Part 10: Determination of trace sulfur in organic liquid chemical products by ultraviolet fluorescence method;

---Part 11: Determination of Trace Arsenic in Liquid Chemical Products Atomic Fluorescence Method.

Warning---Some reagents used in this document are toxic or corrosive, and some operations are dangerous. This document does not disclose If there are possible safety issues, users should strictly follow the relevant regulations and use them correctly, and are responsible for taking appropriate safety and health measures.

1 Scope

This document specifies the method for the determination of trace arsenic in liquid chemical products using atomic fluorescence.

This document is applicable to the determination of trace arsenic in organic liquid chemical products such as hydrocarbons, alcohols, and acids.

When the sample size is 1.0g and the constant volume is 50mL, the detection limit of the method in this document is 0.01mg/kg.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 602 Preparation of standard solutions for impurity determination of chemical reagents

GB/T 3723 General Rules for Sampling Safety of Industrial Chemical Products

GB/T 6680 General Rules for Sampling of Liquid Chemical Products

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

3 Terms and definitions

There are no terms and definitions that need to be defined in this document.

4 Principles of the method

After the arsenic in the sample is digested, add thiourea ascorbic acid solution to convert various forms of arsenic into trivalent arsenic, and then add potassium borohydride to It is reduced to produce arsine, which is decomposed into atomic arsenic by introducing argon gas into the atomizer, and generates atomic fluorescence under the excitation of the emission light of the hollow cathode lamp.

Light, its fluorescence intensity is proportional to the concentration of arsenic in the sample within a certain range. Compared with the standard series, the arsenic content in the sample can be measured.

5 General rules

The water used in this method is all ultra-pure water with a resistivity value of not less than 18Mohm·cm; the reagents used are not specified if other requirements are not specified.

When seeking time, all refer to pure reagents of superior grade; the standard solution for impurity determination used shall be prepared in accordance with the provisions of GB/T 602; the glassware used shall be used Soak in nitric acid solution (1 2) for at least 24h, rinse with tap water repeatedly before use, and then rinse with ultrapure water.