HJ 1082-2019 English PDFUS$229.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. HJ 1082-2019: Soil and sediment--Determination of Cr(VI)--Alkaline digestion/ flame atomic absorption spectrometry Status: Valid
Basic dataStandard ID: HJ 1082-2019 (HJ1082-2019)Description (Translated English): Soil and sediment--Determination of Cr(VI)--Alkaline digestion/ flame atomic absorption spectrometry Sector / Industry: Environmental Protection Industry Standard Classification of Chinese Standard: Z18 Classification of International Standard: 13.080 Word Count Estimation: 10,142 Date of Issue: 2019 Date of Implementation: 2020-06-30 Issuing agency(ies): Ministry of Ecology and Environment HJ 1082-2019: Soil and sediment--Determination of Cr(VI)--Alkaline digestion/ flame atomic absorption spectrometry---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. Soil and sediment--Determination of Cr (VI)-Alkaline digestion/flame atomic absorption spectrometry National Environmental Protection Standard of the People's Republic of China Determination of hexavalent chromium in soil and sediment Extraction of alkaline solution-flame atomic absorption spectrophotometry Soil and sediment-Determination of Cr (VI) -Alkaline digestion/flame atomic absorption spectrometry 2 0 1 9-1 2-3 1 Posted 2 0 2 0-0 6-3 0 Implementation Released by the Ministry of Ecology and Environment ContentsForeword ... ii 1 Scope ... 1 2 Normative references ... 1 3 Methodology ... 1 4 Interference and cancellation ... 1 5 Reagents and materials ... 2 6 Instruments and equipment ... 2 7 Sample ... 3 8 Analysis steps ... 3 9 Results calculation and representation ... 4 10 Precision and accuracy ... 5 11 Quality Assurance and Quality Control ... 6 12 Waste disposal ... 6ForewordIn order to implement the "Environmental Protection Law of the People's Republic of China" Environment, protect human health, standardize the determination method of hexavalent chromium in soil and sediment, and formulate this standard. This standard specifies the alkaline solution extraction-flame atomic absorption spectrophotometry for determination of hexavalent chromium in soil and sediment. This standard is issued for the first time. This standard is formulated by the Department of Eco-Environmental Monitoring, Laws and Standards Department of the Ministry of Ecology and Environment. This standard was drafted. Shanghai Environmental Monitoring Center. This standard is verified by. Tianjin Eco-environment Monitoring Center, the Fifth Institute of Electronics of the Ministry of Industry and Information Technology, Shanghai Environmental Science Research Institute, Shanghai Instrument & Electronics Industry Environmental Monitoring Station, Shanghai Chemical Environmental Protection Monitoring Station and Shanghai Xu Environmental monitoring station in the District. This standard was approved by the Ministry of Ecology and Environment on December 31,.2019. This standard will be implemented from June 30, 2020. This standard is explained by the Ministry of Ecology and Environment. Determination of hexavalent chromium in soils and sediments. Alkali solution extraction-flame atomic absorption Spectrophotometry1 ScopeThis standard specifies the alkaline solution extraction-flame atomic absorption spectrophotometry for determination of hexavalent chromium in soil and sediment. This standard applies to the determination of hexavalent chromium in soil and sediment. When the sample volume of soil and sediment is 5.0 g and the constant volume is 100 ml, the method of hexavalent chromium determined by this standard is checked. The limit of detection was 0.5 mg/kg, and the lower limit of determination was 2.0 mg/kg.2 Normative referencesThis standard refers to the following documents or clauses therein. For undated references, the valid version applies to this standard. GB 17378.3 Marine Monitoring Code Part 3. Sample Collection, Storage and Transportation GB 17378.5 Marine Monitoring Code Part 5. Sediment Analysis HJ 25.2 Technical Guidelines for Soil Pollution Risk Management and Remediation Monitoring on Construction Land HJ 494 Water Quality Sampling Technical Guide HJ 495 Water Quality Sampling Scheme Design Technical Regulations HJ 613 Soil dry matter and moisture determination by gravimetric method HJ/T 91 Technical specifications for surface water and sewage monitoring HJ/T 166 Technical Specifications for Soil Environmental Monitoring3 Method principleUse an alkaline extraction solution with a pH of not less than 11.5 to extract the hexavalent chromium in the sample and spray it into an air-acetylene flame. The ground-state atoms of chromium formed in the warm flame absorb the characteristic spectral lines of chromium. Is proportional to the mass concentration.4 Interference and cancellationIn alkaline environment (pH ≥11.5), the sample is inhibited by magnesium chloride and dipotassium hydrogen phosphate-potassium dihydrogen phosphate buffer solution. The presence of trivalent chromium does not interfere with the determination of hexavalent chromium.5 Reagents and materialsUnless otherwise specified, analytical reagents that meet national standards are used in the analysis, and the experimental water is newly prepared deionized water. water. 5.1 Nitric acid. ρ (HNO3) = 1.42 g/ml, excellent purity. 5.2 Sodium carbonate (Na2CO3). 5.3 Sodium hydroxide (NaOH). 5.4 Magnesium chloride (MgCl2). 5.5 Dipotassium hydrogen phosphate (K2HPO4). 5.6 Potassium dihydrogen phosphate (KH2PO4). 5.7 Dipotassium phosphate-potassium dihydrogen phosphate buffer solution. pH = 7. Weigh 87.1 g of potassium dihydrogen phosphate (5.5) and 68.0 g of potassium dihydrogen phosphate (5.6) in water and dilute to volume. 5.8 Alkaline extraction solution. Weigh 30 g of sodium carbonate (5.2) and 20 g of sodium hydroxide (5.3) in water, dilute to volume to 1 L, and store in dense Sealed in a polyethylene bottle. Before use, the pH must be greater than 11.5. 5.9 Potassium dichromate (K2Cr2O7). reference reagent. Weigh 5.0 g of potassium dichromate in a porcelain crucible, bake in a drying oven at 105 ° C for 2 h, cool to room temperature, and store in a desiccator Inside, spare. 5.10 Hexavalent chromium standard stock solution. ρ = 1000 mg/L. Accurately weigh 2.829 g (accurate to 0.1 mg) of potassium dichromate (5.9) in water and dilute to volume to 1 L. also may Directly purchase a commercially available certified reference material or certified reference solution. 5.11 Hexavalent chromium standard use solution. ρ = 100 mg/L. Accurately transfer 10.0 ml of hexavalent chromium standard stock solution (5.10) into a 100 ml volumetric flask, and make up to the mark with water. Shake well. Store at room temperature for 6 months. 5.12 Filter. 0.45 μm. 5.13 Polyethylene film.6 Instruments and equipment6.1 Flame atomic absorption spectrophotometer. 6.2 Chrome hollow cathode lamp or other light source. 6.3 Stirring and heating device. It has magnetic heating stirrer and temperature control device, which can heat up to 100 ℃. 6.4 Vacuum filtration device. 6.5 pH meter. The accuracy is 0.1 pH unit. 6.6 Balance. Sensitivity is 0.1 mg. 6.7 Nylon screen. 0.15 mm (100 mesh). 6.8 Instruments and equipment commonly used in general laboratories.7 samples7.1 Sample collection and storage Collect and store soil samples in accordance with the relevant requirements of HJ/T 166 or HJ 25.2, and in accordance with HJ/T 91, HJ 494 Or relevant requirements of HJ 495 for collection and preservation of water sediment samples. Collection and preservation of marine sediment samples. Samples should be collected and stored in plastic or glass devices and containers. Containers of metal products. 7.2 Sample preparation According to HJ/T 166, the collected samples were air-dried, crushed, passed through a nylon sieve (6.7), and stored in the laboratory. Note. The sample can also be dried by lyophilization. 7.3 Determination of moisture Determine the dry matter content of soil samples (7.2) according to HJ 613, and determine the sediment samples (7.2) according to GB 17378.5 Moisture content. 7.4 Preparation of test specimens Weigh accurately 5.0 g (accurate to 0.01 g) sample (7.2) in a 250 ml beaker, add 50.0 ml alkaline extract Take the solution (5.8) and add 400 mg of magnesium chloride (5.4) and 0.5 ml of dipotassium phosphate-potassium dihydrogen phosphate buffer solution (5.7). Put the stirrer, seal it with a polyethylene film (5.13), and place it on the stirring heating device (6.3). Stir sample 5 at normal temperature After min, turn on the heating device, heat and stir to 90 ℃ ～ 95 ℃, and keep it for 60 minutes. Remove the beaker and cool to room temperature. Filter with a filter membrane (5.12), place the filtrate in a 250 ml beaker, and adjust the pH of the solution to 7.5 ± 0.5 with nitric acid (5.1). Transfer this solution to a 100 ml volumetric flask, make up to volume with water, shake well, and test. Note 1. When adjusting the pH value of the sample solution, if flocculent precipitation occurs, it needs to be filtered with a filter membrane (5.12). Note 2. If the prepared sample cannot be analyzed immediately, it should be stored under seal at 0 ℃ ～ 4 ℃ for 30 days. 7.5 Preparation of blank sample Without the sample, follow the same procedure as for sample preparation (7.4) to prepare a blank sample.8 Analysis steps8.1 Instrument Reference Conditions Different models of atomic absorption spectrophotometers have different measurement conditions, which can be selected according to the instrument's instruction manual. Recommended instrument measurement conditions are shown in Table 1. Table 1 Instrument reference conditions Element Cr Measurement wavelength (nm) Passband width (nm) 0.2 Flame properties are rich in combustion and reducibility (allow the light spot to pass through the bright blue part of the flame) Secondary sensitivity line (nm) 359.0; 360.5; 425.4 The height of the combustion head is adjusted so that the light source spot passes through the intermediate reaction zone 8.2 Establishment of working curve Pipette 0 ml, 0.10 ml, 0.20 ml, 0.50 ml, 1.00 ml, and 2.00 ml hexavalent chromium standard solution (5.11) respectively Place it in a 250 ml beaker and follow the steps for sample preparation to prepare a working curve solution with a reference concentration of. 0 mg/L, 0.10 mg/L, 0.20 mg/L, 0.50 mg/L, 1.00 mg/L, 2.00 mg/L. Adjust the zero point of the instrument with a blank sample (7.5) and press The absorbance was measured in order from low to high. Set the working curve with the hexavalent chromium concentration as the abscissa and the absorbance as the ordinate line. 8.3 Sample determination The measurement of the sample (7.4) is performed under the same analysis conditions as the establishment of the working curve (8.2). 8.4 Blank test The blank sample (7.5) was measured under the same analysis conditions as the sample measurement (8.3).9 Calculation and representation of results9.1 Calculation of results 9.1.1 Calculation of results for soil samples The content of hexavalent chromium in soil samples w (mg/kg) is calculated according to formula (1). In the formula. w--the content of hexavalent chromium in the soil sample, mg/kg; --concentration of hexavalent chromium in the sample, mg/L; V--constant volume of sample, ml; D--sample dilution factor; m--weigh the weight of the soil sample, g; Wdm-dry matter content of soil sample,%. w = VD mWdm (1) 9.1.2 Results calculation of sediment samples The content w (mg/kg) of hexavalent chromium in the sediment sample is calculated according to formula (2) In the formula. w--the content of hexavalent chromium in the sediment sample, mg/kg; --concentration of hexavalent chromium in the sample, mg/L; V--constant volume of sample, ml; D--sample dilution factor; m--weigh the weight of the sediment sample, g; WH2O--Moisture content of sediment sample,%. 9.2 Representation of results The number of digits after the decimal point of the measurement result is consistent with the detection limit of the method, and a maximum of 3 significant digits are retained. 10 Precision and accuracy 10.1 Precision Six laboratories performed soil samples with hexavalent chromium contents of 8.4 mg/kg, 31.6 mg/kg and 66.5 mg/kg Six repeated determinations. the relative standard deviations in the laboratory were. 5.0% to 14%, 3.8% to 5.8%, and 2.4% to 14%; The relative standard deviations between laboratories were. 7.8%, 4.0%, and 9.1%; the repeatability limits were. 2.6 mg/kg and 4.1 mg/kg, respectively. And 12 mg/kg; the reproducibility limits are. 3.0 mg/kg, 5.2 mg/kg, and 20 mg/kg. Six laboratories performed six replicates of sediment samples with hexavalent chromium levels of 7.8 mg/kg and 24.9 mg/kg Measurement. The relative standard deviations in the laboratory were. 5.2% to 9.3% and 2.3% to 6.4%; the relative standard deviations between laboratories Respectively. 7.9% and 11%; repeatability limits are. 1.6 mg/kg and 3.4 mg/kg; reproducibility limits are. 2.3 mg/kg And 8.4 mg/kg. Six laboratories performed 6 repeated determinations of blank spiked samples with a hexavalent chromium content of 2.0 mg/kg. experiments The indoor relative standard deviation is 2.6% to 8.5%; the relative standard deviation between laboratories is 4.1%; the repeatability limit is 0.34 mg/kg; The reproducibility limit is 0.38 mg/kg. 10.2 Accuracy Six laboratories tested soil standard samples with a hexavalent chromium content of 71.0 (26.6 to 115) mg/kg. relative The error is -18% ～ 5.8%; the final relative error is -6.3% 17.0%. Six laboratories for soil samples with a hexavalent chromium content of 31.6 mg/kg and sediments with a hexavalent chromium concentration of 24.9 mg/kg The samples were spiked and recovered. The spiked recoveries were 86.2% to 108% and 80.9% to 115%, respectively. The final values of the rate are. 94.6% 15.3% and 93.3% 28.4%. w = VD m (1-WH2O) (2) 11 Quality Assurance and Quality Control 11.1 Working curve A working curve should be drawn before the determination of each batch of samples, and the correlation coefficient should be greater than or equal to 0.999. 11.2 Blank test Analyze at least 1 blank sample every 20 samples or each batch (less than 20 samples/batch), determination of blank samples Value should be below the method detection limit. 11.3 Parallel samples Analyze at least 1 parallel sample every 20 samples or batches (less than 20 samples/batch). For deviation ≤20%. 11.4 Matrix Spiking Analyze at least 1 matrix spiked sample every 20 samples or batches (less than 20 samples/batch). The spiked recovery should be It is between 70% and 130%. 12 Waste treatment The waste generated during the experiment should be collected in a centralized manner, be labeled accordingly, and be entrusted to a qualified unit for processing. ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of HJ 1082-2019_English be delivered?Answer: Upon your order, we will start to translate HJ 1082-2019_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 HJ 1082-2019_English with my colleagues?Answer: Yes. The purchased PDF of HJ 1082-2019_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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