GB/T 6150.20-2025Methods for chemical analysis of tungsten concentrates — Part 20: Determination of mercury content — Solid sampling and direct mercury analysis 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 for standardization documents" Drafting is required.

This document is part 20 of GB/T 6150 Chemical analysis methods for tungsten concentrates. GB/T 6150 has published the following parts.

Part 1: Determination of tungsten trioxide content - Gravimetric method on ignition of ammonium tungstate;

Part 2: Determination of tin content - Potassium iodate titration and inductively coupled plasma atomic emission spectrometry;

Part 3: Determination of phosphorus content - Phosphomolybdenum yellow spectrophotometric method and inductively coupled plasma atomic emission spectrometric method;

Part 4: Determination of sulfur content - High frequency induction infrared absorption method and combustion-iodine titration method;

Determination of calcium content EDTA volumetric method and flame atomic absorption spectrometry (GB/T 6150.5); - Part 6: Gravimetric method for determination of moisture content;

Determination of tantalum and niobium content - Plasma emission spectrometry and spectrophotometry (GB/T 6150.7); - Part 8: Determination of molybdenum content - Thiocyanate spectrophotometric method; - Determination of copper content-Flame atomic absorption spectrometry (GB/T 6150.9);

Part 10.Determination of lead content by hydride generation atomic fluorescence spectrometry and flame atomic absorption spectrometry;

Determination of zinc content-Flame atomic absorption spectrometry (GB/T 6150.11);

Part 12.Determination of silicon dioxide content - Silica molybdenum blue spectrophotometric method and gravimetric method;

Part 13.Determination of arsenic content by atomic fluorescence spectrometry and DDTC﹘Ag spectrophotometry;

Determination of manganese content-Ammonium ferrous sulfate volumetric method and flame atomic absorption spectrometry (GB/T 6150.14);

Part 15.Determination of bismuth content - Hydride generation atomic fluorescence spectrometry and flame atomic absorption spectrometry;

Determination of iron content-Sulfosalicylic acid spectrophotometric method (GB/T 6150.16);

Part 17.Determination of antimony content - Atomic fluorescence spectrometry;

Part 18.Determination of barium content - Inductively coupled plasma atomic emission spectrometry;

Part 19.Determination of fluoride content - Ion selective electrode method; - Part 20.Determination of mercury content - Direct determination by solid injection. - Please note that some of the contents of this document may involve patents. The issuing organization of this document does not assume the responsibility for identifying patents.

This document was proposed by China Nonferrous Metals Industry Association.

This document is under the jurisdiction of the National Technical Committee on Standardization of Nonferrous Metals (SAC/TC 243).

This document was drafted by: Jiangxi Tungsten and Rare Earth Product Quality Supervision and Inspection Center (Jiangxi Tungsten and Rare Earth Research Institute), China Nonferrous Metals Guilin Lin Mineral Geology Research Institute Co., Ltd., Shenzhen Zhongjin Lingnan Nonferrous Metals Co., Ltd. Shaoguan Smelter, Xi'an Han Tang Analysis and Testing Co., Ltd.

Co., Ltd., National Standard (Beijing) Inspection and Certification Co., Ltd., Ningbo Customs Technical Center, and Jiangxi University of Science and Technology.

The main drafters of this document are: Xu Na, Ling Honghuan, Li Jianguo, Zeng Qingping, Chen Zhubing, Gu Juanping, Zuo Hongyi, Shi Shilong, Li Shengli, Zhang Xiaoyan, Wang Li, Yue Wenying, Fu Ranran, Zhang Jianbo, Yang Kai, Wang Xianfan.

Introduction

Tungsten concentrate is an important strategic resource. Tungsten and tungsten alloys produced with it as an important industrial raw material have high melting point and high specific gravity.

With the characteristics of heavy weight and high hardness, it is widely used in mechanical processing, metallurgy, mining, electronic telecommunications, construction industry, weapons industry, aerospace, etc.

GB/T 6150 aims to establish a complete, feasible and applicable set of tungsten concentrate product production and trade requirements through experimental research.

Chemical composition analysis method standards. Due to the length of the document, usage requirements, scope of application, and technical independence between various analytical methods, For various reasons, GB/T 6150 is planned to consist of 20 parts.

Part 1: Determination of tungsten trioxide content. The purpose is to establish a method for determining the tungsten trioxide content in tungsten concentrate by gravimetric method.

Part 2: Determination of tin content. The purpose is to establish a titration method and inductively coupled plasma atomic emission spectrometry to determine the content of tungsten Method for determining the tin content in ores.

Part 3: Determination of phosphorus content. The purpose is to establish a spectrophotometric method and an inductively coupled plasma atomic emission spectrometric method for the determination of phosphorus content.

Method for determining phosphorus content in tungsten concentrate.

Part 4: Determination of sulfur content. The purpose is to establish a high frequency infrared absorption method and iodine titration method for determining sulfur content in tungsten concentrate. method.

Part 5: Determination of calcium content. The purpose is to establish a method for determining the calcium content in tungsten concentrate by volumetric method and atomic absorption spectrometry.

Part 6: Determination of wet water content. The purpose is to establish a gravimetric method for determining the wet water content in tungsten concentrate.

Part 7: Determination of tantalum and niobium content. The purpose is to establish an inductively coupled plasma emission spectrometry and spectrophotometry method for the determination of tungsten Method for determining the content of tantalum and niobium in ores.

Part 8: Determination of molybdenum content. The purpose is to establish a method for the spectrophotometric determination of molybdenum content in tungsten concentrate.

Part 9: Determination of copper content. The purpose is to establish a method for determining the copper content in tungsten concentrate by flame atomic absorption spectrometry.

Part 10.Determination of lead content. The purpose is to establish the determination of lead content in tungsten concentrate by atomic fluorescence spectrometry and flame atomic absorption spectrometry. Lead content method.

Part 11.Determination of zinc content. The purpose is to establish a method for determining the zinc content in tungsten concentrate by flame atomic absorption spectrometry.

Part 12.Determination of silicon dioxide content. The purpose is to establish a spectrophotometric and gravimetric method for the determination of silicon dioxide content in tungsten concentrate. Quantitative method.

Part 13.Determination of arsenic content. The purpose is to establish the determination of arsenic content in tungsten concentrate by atomic fluorescence spectrometry and spectrophotometry. method.

Part 14.Determination of manganese content. The purpose is to establish the determination of manganese content in tungsten concentrate by volumetric method and flame atomic absorption spectrometry. method.

Part 15.Determination of bismuth content. The purpose is to establish atomic fluorescence spectrometry and flame atomic absorption spectrometry for the determination of bismuth in tungsten concentrate. Bismuth content method.

Part 16.Determination of iron content. The purpose is to establish a spectrophotometric method for the determination of iron content in tungsten concentrate.

Part 17.Determination of antimony content. The purpose is to establish a method for determining the antimony content in tungsten concentrate by atomic fluorescence spectrometry.

Part 18.Determination of barium content. The purpose is to establish an inductively coupled plasma atomic emission spectrometry method for the determination of barium content in tungsten concentrate. Quantitative method.

Part 19.Determination of fluorine content. The purpose is to establish a method for determining the fluorine content in tungsten concentrate using an ion selective electrode.

Part 20.Determination of mercury content. The purpose is to establish a method for determining the mercury content in tungsten concentrate by direct determination of solid sampling.

Mercury is a toxic and harmful element. During the mining, smelting, processing and utilization of tungsten concentrate, the mercury in it will migrate and concentrate.

The preparation of this document is of great significance to the national strategy of protecting the ecological environment.

The new standard method can not only meet the market demand for tungsten concentrate quality inspection, but also help everyone adopt a unified analysis method.

The law allows product quality testing to be carried out in accordance with the law, which is conducive to the formation of a fair trading environment in the market.

Chemical analysis method of tungsten concentrate Part 20.Determination of mercury content Solid sample direct determination method

1 Scope

This document describes the method for the determination of mercury content in tungsten concentrates.

This document is applicable to the determination of mercury content in tungsten concentrate. Determination range. 0.010 µg/g～15.0 µg/g.

2 Normative references

GB/T 6682

GB/T 8170

3 Terms and definitions

There are no terms or definitions that require definition in this document.

4 Principle

In an oxygen atmosphere, the sample is dried and thermally decomposed in a decomposition furnace. Mercury is atomized and the mercury vapor is carried into the single wavelength by the oxygen flow.

The optical absorption cell measures the absorbance (peak height or peak area) of mercury at a wavelength of 253.7 nm and the amount of mercury is calculated using the standard curve method.

5 Reagents or materials

Unless otherwise stated, only reagents of confirmed analytical grade were used in the analyses.

5.1 Water, GB/T 6682, Grade 2.

5.2 Nitric acid (rho=1.42 g/mL), extra-pure.

5.3 Potassium dichromate solution (10 g/L). weigh 1 g of high-purity potassium dichromate and dissolve it in 100 mL of water.

5.4 Mercury standard stock solution. Weigh 1.354 g of mercuric dichloride that has been dried for 24 h with phosphorus pentoxide, dissolve in a small amount of water, and add Transfer 50 mL of nitric acid (5.2) and 10 mL of potassium dichromate solution (5.3) to a 1 000 mL volumetric flask, dilute to the mark with water, and mix well.

This solution contains 1 000 µg of mercury per 1 mL. Certified standard substances can also be purchased from the market.

5.5 Mercury standard solution A. Pipette 2.00 mL of mercury standard stock solution (5.4) into a 100 mL volumetric flask and add 5 mL of nitric acid.

(5.2), 1 mL of potassium dichromate solution (5.3), dilute to volume with water, and mix well. 1 mL of this solution contains 20 µg of mercury.

5.6 Mercury standard solution B. Pipette 10.0 mL of mercury standard solution A (5.5) into a 100 mL volumetric flask, add 5 mL of nitric acid (5.2), 1 mL of potassium dichromate solution (5.3) is diluted to volume with water and mixed. 1 mL of this solution contains 2 µg of mercury.

5.7 Oxygen (volume fraction not less than 99.99%).

5.8 Sample boat (nickel boat or magnetic boat).