GB/T 12690.7-2021 English PDFUS$249.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 12690.7-2021: Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 7: Determination of silicon content Status: Valid GB/T 12690.7: Historical versions
Basic dataStandard ID: GB/T 12690.7-2021 (GB/T12690.7-2021)Description (Translated English): Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 7: Determination of silicon content Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: H14 Word Count Estimation: 13,172 Issuing agency(ies): State Administration for Market Regulation, China National Standardization Administration GB/T 12690.7-2021: Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 7: Determination of silicon content---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order. Chemical analysis methods for non-rare earth impurities of rare earth metals and their oxides - Part 7.Determination of silicon content ICS 77.120.99 CCSH14 National Standards of People's Republic of China Replace GB/T 12690.7-2003 Non-rare earth impurities in rare earth metals and their oxides Chemical analysis method Part 7.Determination of Silicon Content Released on 2021-10-11 2022-05-01 implementation State Administration for Market Regulation Issued by the National Standardization Management Committee ForewordThis 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 7 of GB/T 12690 "Chemical Analysis Methods of Non-rare Earth Impurities in Rare Earth Metals and Their Oxides". GB/T 12690 The following parts have been released. ---Part 1.Determination of Carbon and Sulfur Content High Frequency-Infrared Absorption Method; ---Part 2.Gravimetric method for determination of ignition loss in rare earth oxides; ---Part 3.Gravimetric method for the determination of water content in rare earth oxides; ---Part 4.Determination of oxygen and nitrogen content by 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 content; ---Part 6.Determination of iron content potassium thiocyanate, 1,10-phenanthroline spectrophotometry; ---Part 7.Determination of silicon content; ---Part 8.Determination of sodium content; ---Part 9.Determination of Chlorine Content Silver Nitrate Turbidimetric Method; ---Part 10.Determination of phosphorus content molybdenum blue spectrophotometry; ---Part 11.Determination of Magnesium Content Flame Atomic Absorption Spectrometry; ---Part 12.Determination of Thorium Content Arsenazo Ⅲ Spectrophotometry and Inductively Coupled Plasma Mass Spectrometry; ---Part 13.Determination of molybdenum and tungsten content inductively coupled plasma emission spectrometry and inductively coupled plasma mass spectrometry; ---Part 14.Determination of the amount of titanium; ---Part 15.Determination of calcium content; ---Part 16.Determination of fluorine content by ion selective electrode method; ---Part 17.Determination of the amount of niobium and tantalum in rare earth metals; ---Part 18.Determination of the amount of zirconium; ---Part 19.Determination of arsenic and mercury content. This document replaces GB/T 12690.7-2003 "Methods for chemical analysis of non-rare earth impurities in rare earth metals and their oxides-Determination of silicon content Molybdenum Blue Spectrophotometry, compared with GB/T 12690.7-2003, except for structural adjustments and editorial changes, the main technical changes are as follows. a) The scope of application of the document has been changed (see Chapter 1, Chapter 1 of the.2003 edition); b) Two chapters "Normative Reference Documents" and "Terms and Definitions" have been added (see Chapter 2 and Chapter 3); c) Modified the principle of molybdenum blue spectrophotometry (see 4.1, Chapter 2 of the.2003 edition); d) The requirements for the standard storage solution of water and silica in the molybdenum blue spectrophotometric method have been changed (see 4.2 introduction, 4.2.10,.2003 (3.10, 3.12 of the annual version); e) Deleted the requirement for hydrochloric acid in the molybdenum blue spectrophotometric method (see 3.3 in the.2003 edition); f) The requirements for instruments and equipment in the molybdenum blue spectrophotometric method have been changed (see 4.3, Chapter 4 of the.2003 edition); g) The requirements for the pretreatment of rare earth oxide samples in the molybdenum blue spectrophotometric method have been changed (see 4.4.1, 5.1 in the.2003 edition); h) Added the requirements for weighing, constant volume and dispensing of samples in the molybdenum blue spectrophotometric method (see Table 1 and Table 2); i) The requirements for sample dissolution in the molybdenum blue spectrophotometric method are changed (see 4.5.4, 6.4.1, 6.4.2, 6.4.3, and 6.4.4 in the.2003 edition); j) Changed the concentration and dosage of ascorbic acid solution in molybdenum blue spectrophotometry, the storage time and color development time of silicomolybdenum heteropoly acid (See 4.5.5, 6.4.5 of the.2003 edition); k) Changed the color development wavelength in molybdenum blue spectrophotometry (see 4.5.6, 4.5.7.2, 6.4.6, 6.5.2 of the.2003 edition); l) Added the requirement for rounding off values in the molybdenum blue spectrophotometric method (see 4.6); m) Changed the precision requirements in the molybdenum blue spectrophotometric method (see 4.7, Chapter 8 of the.2003 edition); n) The chapter "Inductively Coupled Plasma Atomic Emission Spectrometry" has been added (see Chapter 5); o) The chapter "Quality Assurance and Control" has been deleted (see Chapter 9 of the.2003 edition). Please note that some of the contents of this document may involve patents. The issuing agency of this document is not responsible for identifying patents. This document was proposed and managed by the National Rare Earth Standardization Technical Committee (SAC/TC229). Drafting organizations of this document. Baotou Rare Earth Research Institute, Ganzhou Nonferrous Metallurgy Research Institute, Zibo Jiahua New Material Resources Co., Ltd., China Nonferrous Metals Guilin Institute of Mineral Geology Co., Ltd., Leshan Youyan Rare Earth New Material Co., Ltd., Ganzhou Zhanhai New Material Technology Co., Ltd., Inner Mongolia Rare Earth Product Quality Supervision and Inspection Institute, Fujian Changting Jinlong Rare Earth Co., Ltd., Qiandong Rare Earth Group Co., Ltd., Guangdong Branch Industrial Analysis and Testing Center of the Academy, Steel Research Nake Testing Technology Co., Ltd., Jiangsu Jinshi Rare Earth Co., Ltd., Haixi Research Institute of Chinese Academy of Sciences Xiamen Rare Earth Materials Research Institute, National Standard (Beijing) Inspection and Certification Co., Ltd. The main drafters of this document. Chang Cheng, Du Mei, Zhou Kaihong, Yang Xuezheng, Liu Xiaojie, Wang Dongjie, Fang Qiqi, Liu Yanmo, Lu Meiling, Yang Hongbo, Huang Yangcheng, Wang Miao, Hu Zhenzhen, Xiao Yin, Luo Wei, Xie Yiming, Wang Jinfeng, Wen Bin, Xu Siting, Lu Yixin, Liu Zhiyong, Song Lijun, Deng Nan. The previous releases of this document and the documents it replaced are as follows. --- GB/T 8762.3-1988 was first published in 1988, and GB/T 12690.22-1990 was first revised in.1990; --- When it was revised for the second time in.2003 to GB/T 12690.7-2003, GB/T 12690.23-1990 "Rare Earth Metals and Their Oxide chemical analysis methods molybdenum blue spectrophotometric method for the determination of acid-soluble silicon content" (GB/T 12690.23-1990 previous times The version release status is. GB/T 11074.5-1989, GB/T 12690.23-1990); ---This is the third revision.IntroductionIn the field of analysis of the chemical composition of rare earth products, my country has established a test for the total amount of rare earth, non-rare earth impurities, and rare earth impurities. It is a comprehensive standard system. This standard series GB/T 12690 "Chemical Analysis Methods for Non-rare Earth Impurities in Rare Earth Metals and Their Oxides" is based on the original Based on the standard GB/T 12690.12~.26-1990 "Methods for Chemical Analysis of Rare Earth Metals and Their Oxides", GB/T 8762.3- 1988 "Molybdenum Blue Spectrophotometric Method for the Determination of Acid-soluble Silica in Fluorescence Grade Yttrium Oxide", GB/T 8762.4-1988 "Fluorescence Grade Yttrium Oxide Determination of the amount of iron oxide, lead oxide, nickel oxide and copper oxide by emission spectrometry", GB/T 8762.6-1988 "Fluorescence grade europium oxide in oxidation Determination of lead, nickel oxide, iron oxide and copper oxide content by emission spectrometry", GB/T 11074.3~.7-1989 "chemical analysis method of samarium oxide", etc. Standards, and finally form a comprehensive analysis method standard for non-rare earth impurities in all rare earth metals and their oxides. The revised method standard cited Using advanced detection methods, and basically covering all rare earth metals and their rare earth oxide matrix. The establishment of this series of method standards is rare The determination of the content of non-rare earth impurities in earth metals and their oxides provides a quick and accurate method and specification, and has good operability. Non-rare earth impurities in rare earth metals and their oxides Chemical analysis method Part 7.Determination of Silicon Content1 ScopeThis document specifies the methods for determining the total silicon content in rare earth oxides and the acid-soluble silicon content in rare earth metals and their oxides. This document is applicable to the determination of the amount of silicon in rare earth metals and their oxides, including molybdenum blue spectrophotometry (method 1) and inductively coupled plasma Daughter Atomic Emission Spectroscopy (Method 2). Molybdenum blue spectrophotometry (method 1) is suitable for the total silicon content in rare earth oxides and rare earth metals and Determination of acid-soluble silicon content in its oxide, measurement range (mass fraction). 0.0010%~0.20%; inductively coupled plasma atomic emission Spectroscopy (Method 2) is suitable for the determination of acid-soluble silicon content in rare earth metals and their oxides, and the measurement range (mass fraction). 0.010%~ 0.20%. When the scope of analysis of the two methods in this document overlaps, method 1 should be preferred as the arbitration method.2 Normative referencesThe content of the following documents constitutes an indispensable clause of this document through normative references in the text. Among them, dated quotations Only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to This document. GB/T 8170 Numerical rounding rules and the expression and determination of limit values3 Terms and definitionsThe following terms and definitions apply to this document. 3.1 Fulsiliconcontent The content of silicon in rare earth oxides. Note. Calculated based on the mass fraction of silica. 3.2 Acid soluble silicon content The content of silicon in rare earth metals and oxides that can be dissolved in acid solutions. Note. Rare earth metals are calculated by the mass fraction of silicon; rare earth oxides are calculated by the mass fraction of silicon dioxide. 4 Molybdenum blue spectrophotometry (method 1) 4.1 Principle of the method When determining the total silicon content in rare earth oxides, the sample is melted with anhydrous sodium carbonate-boric acid mixed flux and leached with dilute nitric acid; determination of rare earth metals When the acid-soluble silicon content in its oxide, the sample is dissolved with dilute nitric acid. In the acidic medium of 0.12mol/L~0.25mol/L, silicon and molybdenum Ammonium acid generates silico-molybdenum heteropoly acid, decomposes phosphorus and arsenic heteropoly acid with grass-sulfur mixed acid, and uses ascorbic acid to reduce silico-molybdenum heteropoly acid to a blue low-valent complex. The absorbance was measured at a wavelength of 830nm with a spectrophotometer. ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 12690.7-2021_English be delivered?Answer: Upon your order, we will start to translate GB/T 12690.7-2021_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of GB/T 12690.7-2021_English with my colleagues?Answer: Yes. 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