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GB/T 12690.21-2024 English PDF

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GB/T 12690.21-2024: Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 21: Determination of sulfate radical content in rare earth oxides - Barium sulfate turbidimetry
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GB/T 12690.21: Evolution and historical versions

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GB/T 12690.21-2024English229 Add to Cart 3 days [Need to translate] Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 21: Determination of sulfate radical content in rare earth oxides - Barium sulfate turbidimetry Valid GB/T 12690.21-2024
GB/T 12690.21-1990English199 Add to Cart 2 days [Need to translate] Rare-earth metals and their oxides--Determination of phosphorus content--Molybdenum blue spectrophotometric method Obsolete GB/T 12690.21-1990

Standard similar to GB/T 12690.21-2024

GB/T 12690.20   GB/T 12690.12   GB/T 12690.19   

Basic data

Standard ID GB/T 12690.21-2024 (GB/T12690.21-2024)
Description (Translated English) Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 21: Determination of sulfate radical content in rare earth oxides - Barium sulfate turbidimetry
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard H14
Classification of International Standard 77.120.99
Word Count Estimation 11,136
Date of Issue 2024-10-26
Date of Implementation 2025-05-01
Issuing agency(ies) State Administration for Market Regulation, China National Standardization Administration

GB/T 12690.21-2024: Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 21: Determination of sulfate radical content in rare earth oxides - Barium sulfate turbidimetry



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Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 21.Determination of sulfate radical content in rare earth oxides - Barium sulfate turbidimetry Non-rare earth impurities in rare earth metals and their oxides Chemical analysis methods Part 21.Sulfate in rare earth oxides Determination of content by barium sulfate turbidimetry Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides- Part 21.Determination of sulfate radical content in rare earth oxides-Barium sulfate turbidimetry ICS 77.120.99 CCS H 14 National Standard of the People's Republic of China Released on October 26, 2024, implemented on May 1, 2025 State Administration for Market Regulation The National Standardization Administration issued

Table of Contents

Preface Ⅲ Introduction Ⅳ 1 Scope... 1 2 Normative references... 1 3 Terms and Definitions 1 4 Principles... 1 5 Reagents or materials 1 6 Instruments and Equipment... 2 7 samples... 2 8 Test steps... 2 8.1 Test Materials 2 8.2 Parallel tests 2 8.3 Blank test 2 8.4 Preparation of analytical solution 2 8.5 Determination 3 8.6 Drawing and determination of standard curve 3 9 Experimental data processing 4 10 Precision... 4 10.1 Precision Raw Data and Statistics 4 10.2 Repeatability 4 10.3 Reproducibility 5 Preface 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 21 of GB/T 12690 "Chemical analysis of non-rare earth impurities in rare earth metals and their oxides". The following parts have been published. Part 1.Determination of carbon and sulfur content - High frequency infrared absorption method; Part 2.Determination of loss on ignition of rare earth oxides - Gravimetric method; Part 3.Determination of water content in rare earth oxides - Gravimetric method; Part 4.Determination of oxygen and nitrogen content - Pulse infrared absorption method and pulse thermal conductivity method; Part 5.Determination of cobalt, manganese, lead, nickel, copper, zinc, aluminum, chromium, magnesium, cadmium, vanadium and iron; Part 6.Determination of iron content Potassium thiocyanate and 1,10 x phenanthroline spectrophotometric method; Part 7.Determination of silicon content; Part 8.Determination of sodium content; Part 9.Determination of chloride content - Silver nitrate turbidimetric method; Part 10.Determination of phosphorus content - Molybdenum blue spectrophotometric method; Part 11.Determination of magnesium content - Flame atomic absorption spectrometry; Part 12.Determination of thorium and uranium content - Inductively coupled plasma mass spectrometry; Part 13.Determination of molybdenum and tungsten content - Inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry; Part 14.Determination of titanium content; Part 15.Determination of calcium content; Part 16.Determination of fluoride content - Ion selective electrode method; Part 17.Determination of niobium and tantalum in rare earth metals; Part 18.Determination of zirconium content; Part 19.Determination of arsenic and mercury content; Part 20.Determination of trace amounts of fluorine and chlorine in rare earth oxides - Ion chromatography; Part 21.Determination of sulfate content in rare earth oxides—Barium sulfate turbidimetric method. 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 and coordinated by the National Rare Earth Standardization Technical Committee (SAC/TC 229). This document was drafted by. Fujian Jinlong Rare Earth Co., Ltd., National Standard (Beijing) Inspection and Certification Co., Ltd., Baotou Rare Earth Research Institute Institute, Sichuan Leshan Ruifeng Metallurgical Co., Ltd., Ganzhou Chenguang Rare Earth New Materials Co., Ltd., Baotou Huamei Rare Earth Hi-Tech Co., Ltd., Dingnan Dahua New Materials Resources Co., Ltd. The main drafters of this document are. Wang Baohua, Wang Jinfeng, Huang Rongxing, Fang Xiongzhou, Liu Liyuan, Li Jingyan, Liu Pengyu, Quan Longhai, Ye Guifang, Ling Lejiu, Xue Jianping, Miao Fengmei, Mu Yuanyuan, Xie Baoping, Hu Gaixia, and Sun Linjing.

introduction

In the field of chemical composition analysis of rare earth products, my country has established a relatively large number of detection systems for the total amount of rare earths, non-rare earth impurities, and rare earth impurities. GB/T 12690 Chemical analysis of non-rare earth impurities in rare earth metals and their oxides GB/T 12690.12～GB/T 12690.26-1990 "Chemical analysis methods for rare earth metals and their oxides" is the basis, and GB/T 8762.3- 1988 "Determination of Acid-Soluble Silica in Fluorescent Yttrium Oxide by Molybdenum Blue Spectrophotometry", GB/T 8762.4-1988 "Fluorescent Yttrium Oxide Determination of the amount of iron oxide, lead oxide, nickel oxide and copper oxide in yttrium by emission spectrometry" GB/T 8762.6-1988 "Determination of the amount of iron oxide, lead oxide, nickel oxide and copper oxide in yttrium by emission spectrometry" Determination of the amount of lead oxide, nickel oxide, iron oxide and copper oxide by emission spectrometry" GB/T 11074.3 ~ GB/T 11074.7-1989 "Oxygen The standards such as Chemical Analysis Method of Samarium Chloride and others were finally formed into comprehensive analysis standards for non-rare earth impurities in all rare earth metals and their oxides. The combined series of method standards reference advanced detection methods and basically cover all rare earth metals and their rare earth oxide matrices, providing a reference for rare earth The method provides a fast and accurate method for determining the content of non-rare earth impurities in metals and their oxides, and has good operability. According to the differences in test objects, test methods and the differences between rare earth metals and rare earth oxide matrices, GB/T 12690 is proposed to be 21 parts. Part 1.Determination of carbon and sulfur content - High frequency infrared absorption method; Part 2.Determination of loss on ignition of rare earth oxides - Gravimetric method; Part 3.Determination of water content in rare earth oxides - Gravimetric method; Part 4.Determination of oxygen and nitrogen content - Pulse infrared absorption method and pulse thermal conductivity method; Part 5.Determination of cobalt, manganese, lead, nickel, copper, zinc, aluminum, chromium, magnesium, cadmium, vanadium and iron; Part 6.Determination of iron content Potassium thiocyanate and 1,10﹘phenanthroline spectrophotometric method; Part 7.Determination of silicon content; Part 8.Determination of sodium content; Part 9.Determination of chloride content - Silver nitrate turbidimetric method; Part 10.Determination of phosphorus content - Molybdenum blue spectrophotometric method; Part 11.Determination of magnesium content - Flame atomic absorption spectrometry; Part 12.Determination of thorium and uranium content - Inductively coupled plasma mass spectrometry; Part 13.Determination of molybdenum and tungsten content - Inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry; Part 14.Determination of titanium content; Part 15.Determination of calcium content; Part 16.Determination of fluoride content - Ion selective electrode method; Part 17.Determination of niobium and tantalum in rare earth metals; Part 18.Determination of zirconium content; Part 19.Determination of arsenic and mercury content; Part 20.Determination of trace amounts of fluorine and chlorine in rare earth oxides - Ion chromatography; Part 21.Determination of sulfate content in rare earth oxides—Barium sulfate turbidimetric method. The above documents are established in accordance with the conventional detection elements in the production and trade of rare earth metals and their oxides. Each part includes a or multiple detection methods, clearly define the scope of application, selection of reagent materials and test equipment, standardize the test steps, and pass the Multiple tests and verifications provide precision raw data, establishing rigorous and standardized work for the quality verification of rare earth metals and their oxides Base. Currently, in the production and trading of many rare earth oxides, there are restrictions on sulfate. When testing, most laboratories in the industry refer to GB/T 16484.12, but its test conditions are not completely applicable to rare earth oxides. Therefore, it is necessary to establish a unified, rapid and accurate standard for the determination of sulfate content in rare earth oxides. Through a large number of conditional tests, we standardized every detail of the testing process and established standardized, easy-to-operate and highly accurate testing standards. Non-rare earth impurities in rare earth metals and their oxides Chemical analysis methods Part 21.Sulfate in rare earth oxides Determination of content by barium sulfate turbidimetry

1 Scope

This document describes a method for the determination of sulfate content in rare earth oxides. This document is applicable to the determination of sulfate content in rare earth oxides. Determination range (mass fraction). 0.010% to 0.20%.

2 Normative references

The contents of the following documents constitute the essential clauses of this document through normative references in this document. For referenced documents without a date, only the latest version (including all amendments) applies to this document. In this document. GB/T 6379.2 Accuracy (trueness and precision) of measurement methods and results Part 2.Determination of the repeatability of standard measurement methods Basic methods of sex and reproducibility GB/T 6682 Specifications and test methods for water used in analytical laboratories GB/T 8170 Rules for rounding off values and expression and determination of limit values JJG 178 UV, Visible, and Near-Infrared Spectrophotometer 3 Terms and Definitions There are no terms or definitions that require definition in this document.

4 Principles

The sample is dissolved in acid (or after acid dissolution, excess sodium hydroxide solution is added to form rare earth hydroxide precipitation, which is filtered to allow sulfate to react with Rare earth separation), in the presence of glycerol stabilizer in dilute hydrochloric acid medium, add barium chloride to form a barium sulfate suspension, and then The absorbance was measured at 400 nm using a photometer, and the sulfate mass fraction was calculated. 5 Reagents or materials Unless otherwise specified, only reagents of analytical grade or higher and grade II water that complies with the laboratory standard GB/T 6682 were used in the analysis. Certified standard solutions are preferred. 5.1 Hydrogen peroxide [w (H2O2) ≥ 30%]. 5.2 Perchloric acid (ρ = 1.67 g/mL). 5.3 Nitric acid (1 1). 5.4 Hydrochloric acid (1 1). 5.5 Ammonia (1 4).

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