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HJ 754-2015 English PDFUS$249.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. HJ 754-2015: Water quality. Determination of atrazine by Gas chromatography Status: Valid
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HJ 754-2015: Water quality. Determination of atrazine by Gas chromatography---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.Water quality.Determination of atrazine by Gas chromatography National Environmental Protection Standard of the People's Republic Determination of water quality atrazine by gas chromatography Published on.2015-10-22 2015-12-01 Implementation Ministry of Environmental Protection released i directory Foreword..ii 1 Scope..1 2 Normative references.1 3 method principle..1 4 Reagents and materials.1 5 instruments and equipment.1 6 samples. 2 7 Analysis steps..2 8 Calculation and representation of results. 3 9 precision and accuracy. 4 10 Quality Assurance and Quality Control..4 11 Waste treatment.4 ForewordTo implement the Environmental Protection Law of the People's Republic of China and the Law of the People's Republic of China on Water Pollution Prevention and Control, to protect the environment, To ensure human health, standardize the determination method of atrazine in water, and develop this standard. This standard specifies the gas chromatographic method for the determination of atrazine in water. This standard is the first release. This standard was formulated by the Science and Technology Standards Department of the Ministry of Environmental Protection. This standard is mainly drafted by. Taizhou Environmental Monitoring Center Station. This standard is verified by. Jiangsu Environmental Monitoring Center, Wuxi Environmental Monitoring Center Station, Suzhou Environmental Monitoring Center, Changzhou Environmental Monitoring Center, Zhenjiang Environmental Monitoring Center Station and Taizhou Environmental Monitoring Center Station. This standard was approved by the Ministry of Environmental Protection on October 22,.2015. This standard has been implemented since December 1,.2015. This standard is explained by the Ministry of Environmental Protection.1 water quality atrazine determination gas chromatographyWarning. The solvents and reagents used in the experiment are all toxic. The sample preparation process should be carried out in a fume hood. Wear protective equipment as required to avoid contact with skin and clothing.1 Scope of applicationThis standard specifies the gas chromatographic method for the determination of atrazine in water. This standard applies to the determination of atrazine in surface water, groundwater, domestic sewage and industrial wastewater. When the sample size is 100 ml, the detection limit of atrazine is 0.2 μg/L, and the lower limit of determination is 0.8 μg/L.2 Normative referencesThe contents of this standard refer to the following documents or their terms. For undated references, the valid version is appropriate. Used in this standard. HJ/T 91 Surface Water and Wastewater Monitoring Technical Specifications HJ/T 164 Technical Specifications for Groundwater Environmental Monitoring3 Principle of the methodThe atrazine in the water is extracted with dichloromethane, and the extract is dried over anhydrous sodium sulfate, concentrated, and converted into acetone. Agent, after constant volume, separated and detected by gas chromatograph-nitrogen phosphorus detector (NPD), qualitative according to retention time, external standard method Quantitative.4 reagents and materialsUnless otherwise stated, analytically pure reagents and laboratory water in accordance with national standards were used for the analysis. 4.1 Dichloromethane (CH2Cl2). pesticide residue grade. 4.2 Acetone (C3H6O). pesticide residue grade. 4.3 n-hexane (C6H14). pesticide residue grade. 4.4 Ethyl acetate (C4H8O2). pesticide residue grade. 4.5 sodium chloride (NaCl) It was fired in a muffle furnace at 400 ° C for 4 h, cooled and placed in a ground glass bottle and stored in a desiccator. 4.6 anhydrous sodium sulfate (Na2SO4) It was fired in a muffle furnace at 400 ° C for 4 h, cooled and placed in a ground glass bottle and stored in a desiccator. 4.7 Atrazine standard solution. ρ = 100 mg/L, the solvent is acetone, commercially available. 4.8 Carrier gas. nitrogen, purity ≥99.999%. 4.9 Combustion gas. hydrogen, purity ≥ 99.95%. 4.10 Gas-assisted gas. oil-free compressed air, purified by 5 Å molecular sieve.5 Instruments and equipment5.1 Gas Chromatograph. Nitrogen Phosphorus Detector (NPD). 5.2 Column. quartz capillary column, 30 m × 0.25 mm, coated with 5% phenylmethylpolysiloxane, film thickness 0.25 μm, 2 or other equivalent capillary column. 5.3 Auxiliary Qualitative Column. Quartz capillary column, 30 m × 0.25 mm, internally coated with 35% phenylmethylpolysiloxane, film thickness 0.25 μm, or other equivalent capillary column. 5.4 Concentration device. A device with comparable performance such as a nitrogen blow concentrator, a rotary evaporator or a KD concentrator. 5.5 separatory funnel. 250 ml. 5.6 Microinjectors. 10 μl, 50 μl and 100 μl. 5.7 Purification column. silica gel type adsorption column, 500 mg/6 ml, commercially available. 5.8 Common instruments and equipment used in general laboratories.6 samples6.1 Sample collection and preservation Samples were taken with reference to the relevant regulations of HJ/T 91 and HJ/T 164. Use 500 ml hard ground glass bottle or have poly four Samples are taken from the threaded glass bottle of the vinyl fluoride cover. The sample should be filled with the sample bottle and sealed, placed in a refrigerator at 4 °C. Save inside. The sample should be extracted within 7 days after sampling. 6.2 Preparation of samples 6.2.1 Extraction Take 100 ml of sample into a 250 ml separatory funnel (5.5), add 5 g of sodium chloride (4.5), dissolve and add 15 ml Dichloromethane (4.1), shaken for 5 min, allowed to stand for 15 min, layered, collected organic phase, repeated extraction, combined extraction The liquid was taken and dried over anhydrous sodium sulfate (4.6). Note 1. If emulsification occurs during the extraction process, mechanical separation can be used to complete the two-phase separation, including agitation, centrifugation, and ultrasonic methods. Demulsification, can also be used to break the milk by freezing. 6.2.2 Purification For samples with complex compositions, the following purification method can be used. concentrate the extract (6.2.1) to near dry and then add positive About 1 ml of hexane is used for purification. Purification step. activate the purification column (5.7) with 10 ml of n-hexane (4.3), wait for the column When the hexane is nearly dry, the n-hexane concentrate is transferred to a purification column, and the concentrating tube is washed 2 to 3 times with 5 ml of n-hexane. On the upper column, control the elution speed to about 2.5 ml/min (about 1 drop/s), discard the eluent; then use a 10 ml volume ratio of 9.1. Elution with hexane and ethyl acetate (4.4) was carried out to control the elution rate to about 2.5 ml/min (about 1 drop/s), and the eluate was collected. Note 2. The cleaner groundwater, surface water and domestic sewage extract (6.2.1) can be directly pressed (6.2.3) without purification steps. The steps are processed. 6.2.3 Concentration and replacement of solvents Concentrate the extract (6.2.1) or the purified eluent (6.2.2) with a concentration unit (5.4) and convert the solvent to acetone. (4.2), make up to 1.0 ml. The samples were stored in a 4 ° C refrigerator and analyzed within 40 d. 6.3 Preparation of blank samples While analyzing the sample, take 100 ml of experimental water instead of the sample, follow the same procedure as the preparation of the sample (6.2). A blank sample was prepared.7 Analysis steps7.1 Gas Chromatography Reference Conditions Inlet temperature. 240 ° C, split injection, split ratio 10.1; oven temperature. initial temperature 40 ° C, keep 3 3 min, rise to 190 ° C at 30 ° C/min, hold for 5 min, then increase to 250 ° C at 30 ° C/min, keep 5 min; carrier gas flow rate. 1.0 ml/min; detector temperature. 300 ° C, hydrogen flow rate. 3.0 ml/min, air flow rate. 60.0 Ml/min; injection volume. 1.0 μl. 7.2 Establishing a calibration curve Take 5 5.0 ml volumetric flasks, add appropriate amount of acetone (4.2), and add 5.0 with a micro-syringe (5.6). Ll, 10.0 μl, 20.0 μl, 40.0 μl, 100.0 μl of atrazine standard solution (4.7), make up to volume with acetone (4.2), and mix. The concentration of atrazine was 0.10 mg/L, 0.20 mg/L, 0.40 mg/L, 0.80 mg/L, 2.00 mg/L, respectively. Standard series. The concentration of the standard series (mg/L) is plotted on the abscissa, and the corresponding peak area (or peak height) of the chromatogram is vertical. Coordinates, establish a standard curve. 7.3 Sample determination The sample was treated according to the preparation method (6.2) of the sample, and then measured according to the gas chromatography reference condition (7.1). Note 3. When the actual sample concentration exceeds the calibration curve range, dilute the sample to the linear range of the calibration curve before sample preparation (6.2) And determination. 7.4 Blank test The prepared blank sample (6.3) was measured according to the same instrumental analysis conditions as the standard curve.8 Calculation and representation of results8.1 qualitative analysis The target compound is characterized based on the retention time of the target in the sample and the target in the standard series. The retention time window t±3S was established before sample analysis. t is the retention of the target compound at each concentration level at the initial calibration Time average, S is the standard deviation of the retentio...... |