GB/T 3884.2-2025 English PDFGB/T 3884.2: Historical versions
Basic dataStandard ID: GB/T 3884.2-2025 (GB/T3884.2-2025)Description (Translated English): Methods for chemical analysis of copper concentrates - Part 2: Determination of gold and silver contents - Flame atomic absorption spectrmetric method and fire assay method Sector / Industry: National Standard (Recommended) Date of Implementation: 2026-03-01 Older Standard (superseded by this standard): GB/T 3884.2-2012, GB/T 3884.14-2012 GB/T 3884.2-2012: Methods for chemical analysis of copper concentrates - Part 2: Determination of gold and silver contents - Flame atomic absorption spectrometric method and fire assay method---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. Methods for chemical analysis of copper concentrates.Part 2. Determination of gold and silver contents.Flame atomic absorption spectrmetric method and fire assay method ICS 77.120.60 H13 National Standards of People's Republic of China Replace GB/T 3884.2-2000 Copper concentrate chemical analysis method Part 2. Determination of gold and silver Flame atomic absorption spectrometry and fire assay Part 2.Determinationofgoldandsilvercontents- Released on.2012-12-31 2013-10-01 implementation General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China China National Standardization Administration issued ForewordGB/T 3884 "Chemical Analysis Method for Copper Concentrate" is divided into 14 parts. --- Part 1. Determination of copper content iodometric method; --- Part 2. Determination of gold and silver content by flame atomic absorption spectrometry and fire assays; ---Part 3. Determination of sulfur content - Gravimetric method and combustion - titration method; ---Part 4. Determination of the amount of magnesium oxide - Atomic absorption spectrometric method; ---Part 5. Determination of the amount of fluorine ion selective electrode method; -- Part 6. Determination of lead, zinc, cadmium and nickel - Atomic ---Part 7. Determination of lead content by Na2EDTA titration; ---Part 8. Determination of zinc content by Na2EDTA titration; ---Part 9. Determination of arsenic and bismuth - Hydride generation - atomic fluorescence spectrometry, potassium bromate titration and diethyl dithio Silver formic acid spectrophotometry; ---Part 10. Determination of enthalpy - hydride generation - atomic fluorescence spectrometry; --- Part 11. Determination of mercury content by cold atomic absorption spectrometry; --- Part 12. Determination of fluorine and chlorine content - Ion chromatography; --- Part 13. Determination of copper content electrolysis; --- Part 14. Determination of gold and silver content Fire test gravimetric method and atomic absorption spectrometry. This part is the second part. This part is drafted in accordance with the rules given in GB/T 1.1-2009. This part replaces GB/T 3884.2-2000 "Determination of gold and silver in chemical analysis methods for copper concentrates", and GB/T 3884.2-2000 In comparison, the following changes have occurred mainly. --- Modified the text format; --- Added precision and test report terms. This part is under the jurisdiction of the National Nonferrous Metals Standardization Technical Committee (SAC/TC243). This section is responsible for drafting unit. Daye Nonferrous Metal Group Holdings Co., Ltd. This section drafted by. Daye Nonferrous Metals Group Holdings Limited. Participated in the drafting of this section. Beijing Research Institute of Mining and Metallurgy, Tongling Nonferrous Metals Group Holdings Co., Ltd., Jiangxi Copper Industry Co., Ltd. Division, Zhongtiaoshan Nonferrous Metals Group Co., Ltd., Yunnan Copper Co., Ltd., Zhuzhou Smelting Group Co., Ltd., Zijin Mining Group Co., Ltd., MCC Huludao Nonferrous Metals Group Co., Ltd., Hunan Shuikoushan Nonferrous Metals Group Co., Ltd., Yanggu Xiangguang Copper Co., Ltd., Hunan Nonferrous Metal Research Institute. The main drafters of this part of Method 1 are. Yuan Gongqi, Xiao Zehong, Li Xiaoyu, Feng Yuan, Wang Yuying, Zhou Xiaokai, Wang Junyi, Chen Yu, Ma Lijun, Zhang Yu, Mu Xiumei, Zheng Wenying, Zhang Yanyun, Peng Jian, Zhang Hongxian, Chi Fenghua, Cao Yan, Luo Yongfeng, Zhang Yongzhong, Li Bing. The main drafters of this part of Method 2. Wang Yongbin, Yuan Gongqi, Feng Congxin, Huang Shangyuan, Xiong Meiyu, Yuan Yuxia, Liu Chenghua, Li Qinmei, Wang Datong, Chang Yuxiang, Zhang Zhongxiang, Han Yunshan, Zhang Ming, Chen Liqing, Liu Zhiqiang, Ma Ning, Wang Yue, Zeng Guangming, Zhou Hongding, Zhang Qiaoyan. The previous versions of the standards replaced by this section are. ---GB/T 3884.2-1983, GB/T 3884.14-1986, GB/T 3884.15-1986, GB/T 3884.2-2000. Copper concentrate chemical analysis method Part 2. Determination of gold and silver Flame atomic absorption spectrometry and fire assay1 ScopeThe method specifies a method for determining the gold and silver content of copper concentrate. The method is applicable to the determination of gold and silver content in copper concentrates. Method 1 Determination range. Silver. 10.0g/t~300.0g/t; Method 2 The range is. gold. 0.50g/t ~ 40.00g/t; silver. 50.0g/t ~ 2500.0g/t. 2 Method 1 Flame atomic absorption spectrometry 2.1 Method summary The sample was dissolved in nitric acid and perchloric acid. In a dilute hydrochloric acid medium, an atomic absorption spectrometer was used at a wavelength of 328.1 nm to produce an air-acetylene fire. The flame measures the absorbance of silver, minus the background absorption, and calculates the amount of silver according to the standard curve. 2.2 Reagents Unless otherwise stated, only analytically pure reagents and distilled or deionized water or water of comparable purity were used in the analysis. 2.2.1 Ammonium hydrogen fluoride. 2.2.2 Hydrochloric acid (ρ = 1.19 g/mL). 2.2.3 Hydrochloric acid (1 9). 2.2.4 Nitric acid (ρ = 1.42 g/mL). 2.2.5 Nitric acid (1 1). 2.2.6 Perchloric acid (ρ = 1.67 g/mL). 2.2.7 Silver standard storage solution. Weigh 0.1000g of pure silver (wAg≥99.99%) in a.200mL beaker, add 20mL of nitric acid (2.2.5), heated to complete dissolution, cooled to room temperature, transferred to a.200mL brown volumetric flask, diluted with chlorine-free ion exchange water to the scale, mixed uniform. 1 mL of this solution contained 500 μg of silver. 2.2.8 Silver standard solution. Pipette 10.00mL silver standard storage solution (2.2.7) in a 100mL volumetric flask and dilute with hydrochloric acid (1 9) Mix to the scale. 1 mL of this solution contained 20 μg of silver. 2.3 Instruments Atomic absorption spectrometer with silver hollow cathode lamp. Under the best working conditions of the instrument, anyone who can achieve the following indicators can be used. --- Characteristic concentration. In the solution consistent with the matrix of the measurement sample solution, the characteristic concentration of silver should be no more than 0.018 μg/mL. ---Precision. 10 times absorbance is measured with the highest concentration standard solution, and the standard deviation should not exceed 1.0% of the average absorbance. The minimum concentration of the standard solubility (not the "zero" standard solubility) is measured 10 times of absorbance, the standard deviation should not exceed the highest concentration mark The average absorbance of the quasi-solution is 0.5%. ---Working curve linearity. The working curve is divided into five segments according to the concentration, and the ratio of the difference between the absorbance difference of the highest segment and the absorbance of the lowest segment is Not less than 0.85. 2.4 Sample 2.4.1 The sample size should be no more than 100μm. 2.4.2 The sample should be dried at 100 ° C ~ 105 ° C for 1 h and then placed in a desiccator to cool to room temperature. 2.5 Analysis steps 2.5.1 Samples The sample was weighed according to Table 1 to the nearest 0.0001 g. Table 1 Sample quality and volumetric volume Silver mass fraction/(g/t) Sample mass/g Determination volume/mL Add hydrochloric acid (3.2)/mL 10.0~40.0 0.50 25 2.5 >40.0~100.0 0.50 50 5.0 >100.0~300.0 0.30 100 10.0 2.5.2 Number of measurements The test was carried out twice independently and the average value was taken. 2.5.3 Blank test A blank test was carried out along with the sample. 2.5.4 Determination 2.5.4.1 Place the sample (2.5.1) in a 250 mL beaker, add a small amount of water to wet, add 15 mL of nitric acid (2.2.4), and cover the watch. Heat and dissolve, occasionally shake, dissolve to a small volume, add 5mL perchloric acid (2.2.6) and continue to heat up to smoke, continue to dissolve at low temperature until There is no black residue at the bottom of the cup, take it off slightly, add 5mL hydrochloric acid (2.2.2), continue heating to perchloric acid, white smoke, steam to wet salt, remove and cool. Note. Add a small amount of ammonium bifluoride when the silicon is high. 2.5.4.2 Add hydrochloric acid (2.2.2) according to Table 1. Wash the watch and the cup wall with water, heat to dissolve the salt, and remove to cool to room temperature. Transfer the solution to a volumetric flask, dilute to the mark with water, mix, and let stand (or dry filter). 2.5.4.3 Use air-acetylene flame at the wavelength of 328.1nm of the atomic absorption spectrometer to adjust the blank test solution along with the sample. Zero, measure the absorbance of the test solution, subtract the background absorption, and find the corresponding silver concentration from the working curve. 2.5.5 Drawing of the working curve 2.5.5.1 Pipette 0mL, 1.00mL, 2.00mL, 3.00mL, 4.00mL, 5.00mL silver standard solution (2.2.8), respectively Add a 10.0 mL hydrochloric acid (2.2.2) to a set of 100 mL volumetric flasks, dilute to the mark with water, and mix. 2.5.5.2 Under the same conditions as the measurement sample solution, zero the solution with “zero” concentration solution, measure the silver standard solution at the wavelength of 328.1 nm. The absorbance of the liquid is plotted on the abscissa with the silver concentration and the corresponding absorbance is plotted on the ordinate. 2.6 Calculation of analysis results The content of silver is expressed in mass fraction wAg, and the value is expressed in g/t, which is calculated according to formula (1). wAg=ρ ·V1 M0 (1) In the formula. ρ --- the mass concentration of silver found in the working curve, in micrograms per milliliter (μg/mL); V1---the volume of the sample solution in milliliters (mL); M0---The mass of the sample in grams (g). The result of the calculation is expressed to one decimal place. 2.7 precision 2.7.1 Repeatability The measured values of two independent test results obtained under repetitive conditions, within the average range given below, the two test results The absolute difference does not exceed the repeatability limit (r), the case of exceeding the repeatability limit (r) does not exceed 5%, and the repeatability limit (r) is linear according to the data in Table 2. Interpolated or extended. Table 2 Repeatability limits wAg/(g/t) 14.7 69.5 110.8 190.6 313.8 r/(g/t) 2.9 4.9 7.6 9.3 15.4 2.7.2 Reproducibility The measured values of the two independent test results obtained under reproducibility conditions are within the average range given below, and the two test results The absolute difference is not greater than the reproducibility limit (R), the reproducibility limit (R) is less than 5%, and the reproducibility limit (R) is based on the data in Table 3. Sexual interpolation or extension method. Table 3 Reproducibility limits wAg/(g/t) 14.7 69.5 110.8 190.6 313.8 R/(g/t) 5.0 8.4 13.0 15.9 26.2 2.8 Test report The test report should at least give the following aspects. ---sample; ---usage instructions; --- Analysis results and their representation; --- The difference from the basic analysis steps; --- Anomaly observed in the measurement; --- Test date. 3 method 2 fire test method 3.1 Method summary The sample is compounded and melted at a high temperature, and the precious metal in the molten metal lead capture sample forms a lead buckle, and other substances in the sample are mixed with the flux. It becomes fusible slag. The lead buckle is ash-blended to obtain gold and silver granules, and the impurities on the surface of the granules are removed, and the amount of silver is determined by titration with gold nitrate. The amount of gold is determined by the method. 3.2 Reagents Unless otherwise stated, only analytically pure reagents and distilled or deionized water or water of comparable purity were used in the analysis. 3.2.1 Sodium carbonate. industrial pure, powdery. 3.2.2 Lead oxide. industrially pure, powdery (containing gold < 0.01g/t, containing silver < 0.5g/t). 3.2.3 Silica. industrially pure, powdered. 3.2.4 Borax. Powdery. 3.2.5 Starch. powder. 3.2.6 Potassium nitrate, powdered. 3.2.7 Sodium chloride. industrially pure, powdered. 3.2.8 Sterling silver. 99.99%. 3.2.9 Lead foil. thickness 0.1mm~0.15mm, mass 3g~5g, square, containing less than 0.1g/t. 3.2.10 Nitric acid (ρ=1.42g/mL), excellent grade pure. 3.2.11 Nitric acid (1 7), free of chloride. 3.2.12 Nitric acid (1 1), free of chloride. 3.2.13 Ammonium ferric sulfate indicator. Take a saturated solution of ammonium ferric sulfate, add three parts of nitric acid (1 3), and mix. 3.2.14 Potassium thiocyanate standard titration solution 3.2.14.1 Preparation. Weigh 0.5g potassium thiocyanate, place it in a 100mL beaker, dissolve it with water, transfer it to 1000mL, volumetric flask, dilute Mix to the scale. After standing for one week, filter and set aside. 3.2.14.2 Calibration. Weigh three parts of 10.00mg~15.00mg of pure silver (3.2.8) into 50mL porcelain crucible (3.3.9), add 10mL~15mL nitric acid (3.2.12), slightly dissolved and steamed to about 1mL~2mL, adding a small amount of water and 0.5mL ammonium ferric sulfate indication The agent (3.2.13) is titrated to a light red with a potassium thiocyanate standard titration solution (3.2.14). Calculate the actual concentration of the potassium thiocyanate standard titration solution according to formula (2). c= m1M·V2 (2) In the formula. c --- actual concentration of potassium thiocyanate standard titration solution, the unit is mol per liter (mol/L); M1---Weigh the mass of silver in milligrams (mg); V2---the volume of potassium thiocyanate standard titration solution consumed by titration of silver, the unit is milliliter (mL); M---Molecular mass of silver in grams per mole (g/mol), [M(Ag) = 107.868]. When the extreme difference between the three calibration results is not more than 4×10-5mol/L, take the average of the three calibration results, otherwise recalibrate. 3.3 Instruments and equipment 3.3.1 Balance. 3.3.1.1 Tray balance. 1 g. 3.3.1.2 Analytical balance. 0.001 g. 3.3.1.3 Microbalance. Sensing amount 0.01mg. 3.3.1.4 Ultra-micro balance. 0.001mg. 3.3.2 Test furnace. The maximum heating temperature is not lower than 1200 °C. 3.3.3 Clay 坩埚. The material is refractory clay with a volume of about 300mL. 3.3.4 Electric blast oven. 3.3.5 Grey dish machine. 3.3.6 Sample pulverizer. 3.3.7 Ashware. The top inner diameter is 35mm, the bottom outer diameter is 40mm, the height is 30mm, and the depth is about 17mm. Method. 1 part by weight of ashes and 3 parts by weight of cement (No. 425). Add appropriate amount of water and mix well, press on the ash machine, yin After three months of use, spare. 3.3.8 Porcelain crucible (low type). The volume is 30mL. 3.3.9 Porcelain crucible. The volume is 50mL. 3.3.10 Cast iron mold. 3.3.11 Hemostatic forceps. 3.4 Sample 3.4.1 The sample size should be no more than 100μm. 3.4.2 The sample should be dried at 100 ° C ~ 105 ° C for 1 h, placed in a desiccator, cooled to room temperature. 3.5 Analysis steps 3.5.1 Samples According to the content of copper, gold, silver and sulfur in the sample, 15g~25g samples were weighed to the nearest 0.001g. 3.5.2 Number of measurements The (at least) secondary measurements were performed independently and the average was taken. 3.5.3 Blank test 3.5.3.1 A blank test is carried out along with the sample (three samples are taken in parallel and the average value is taken). 3.5.3.2 Test method Weigh 25g sodium carbonate (3.2.1),.200g lead oxide (3.2.2), 15g silica (3.2.3), 7g borax (3.2.4), 4g starch (3.2.5), covering about 10mm thick sodium chloride (3.2.7), the following is carried out according to 3.5.4.2~3.5.4.4. 3.5.4 Determination 3.5.4.1 Ingredients According to the chemical composition of the sample and the amount of the sample, the ingredients were mixed in a crucible according to the following principles and mixed to cover about 10 mm thick sodium chloride. Sodium carbonate. 1.5 times the amount of the sample. Lead oxide. 30 times the amount of copper or 25 times the amount of sulfur plus lead deduction (if iron, arsenic, antimony, antimony, nickel, etc. are high, increase the amount appropriately). Silica. The amount added is calculated as the slag type equal to 0.5 silicic acid. Potassium nitrate and starch. According to the content of sulfur and carbon in the sample, it is added as appropriate. 3.5.4.2 Melting Place the prepared clay crucible (3.3.3) in a 900 °C test gold furnace (3.3.2), heat up 30min to 1100 °C, keep warm After 15 minutes of boiling, the molten material was poured into a preheated cast iron mold (3.3.10), and the crucible was retained for remelting. After cooling, lead buckle and The slag is separated and the slag is retained for further processing. Hammer the lead button into a cube. Suitable lead buckles should be bright on the surface and weigh 30g~45g, otherwise The ingredients should be re-adjusted and melted. The slag is removed from the covering agent and recovered in the original crucible. 3.5.4.3 Ash blowing Put the lead button into the ash dish (3.3.7) which has been preheated for 30 min in the 900 °C test gold furnace (3.3.2), and close the furnace door. 1min~2min, after the black film on the surface of the lead liquid is removed, the furnace door is opened slightly to lower the furnace temperature to 840 °C as soon as possible, and the ash is blown. After that, the ash is over. Move the ash dish to the door of the furnace, put it into the ash dish after a little cold, and keep the ash dish residue for disposal. 3.5.4.4 points Use the hemostatic forceps (3.3.11) to remove the gold and silver particles, brush the adhered impurities, hammer into thin slices, place in 30mL porcelain crucible (3.3.8), add 10mL hot nitric acid (3.2.11), keep the near boiling on the low temperature electric heating plate, evaporate to about 2mL, take off slightly cold, then add 10mL hot nitric acid (3.2.12), steam to about 2 mL, remove and cool. Wash the wall with hot water and transfer the solution to 50 mL porcelain crucible by pouring (3.3.9) In the middle, the wall is washed twice with hot water. After cooling, add about 0.5mL of ammonium ferric sulfate indicator (3.2.13), and dissolve it with potassium thiocyanate standard. The liquid (3.2.14) is titrated to light red, which is the end point. The porcelain crucible containing gold particles is placed on a high temperature electric furnace for 5 minutes, and then cooled. Weighing. Note. When the ratio of silver to gold in the granules is less than 3.1, pure silver should be added to the granules by weighing 3 times the merging amount of silver and combining the leaching and sterling silver with lead foil. package. The following is performed according to 3.5.4.3~3.5.4.4. 3.5.4.5 Correction (residue reprocessing) The slag and ash dish stored in the mash are placed in a sample pulverizer (3.3.6), and then 50 g of sodium carbonate (3.2.1) and 15 g of dioxide are added. Silicon (3.2.3), 20g borax (3.2.4), 4g starch (3.2.5), stir well, cover 10mm thick sodium chloride (3.2.7), the following is 3.5.4.2~ 3.5.4.4 proceed. 3.6 Expression of analysis results The content of gold and silver is expressed by mass fraction wAu and wAg, and the value is ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 3884.2-2025_English be delivered?Answer: Upon your order, we will start to translate GB/T 3884.2-2025_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 3884.2-2025_English with my colleagues?Answer: Yes. The purchased PDF of GB/T 3884.2-2025_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet.Question 3: Does the price include tax/VAT?Answer: Yes. 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