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HJ 974-2018 English PDF

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HJ 974-2018: Soil and sediment - Determination of 11 elements - Alkaline fusion and inductively coupled plasma optical emission spectrometry
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Basic data

Standard ID HJ 974-2018 (HJ974-2018)
Description (Translated English) Soil and sediment - Determination of 11 elements - Alkaline fusion and inductively coupled plasma optical emission spectrometry
Sector / Industry Environmental Protection Industry Standard
Classification of Chinese Standard Z18
Word Count Estimation 19,136
Issuing agency(ies) Ministry of Ecology and Environment

HJ 974-2018: Soil and sediment - Determination of 11 elements - Alkaline fusion and inductively coupled plasma optical emission spectrometry


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Soil and sediment - Determination of 11 elements - Alkaline fusion and inductively coupled plasma optical emission spectrometry National Environmental Protection Standard of the People's Republic Determination of 11 elements in soil and sediment Alkali fusion-inductively coupled plasma optical emission spectrometry Soil and sediment - Determination of 11 elements - Alkaline fusion And inductively coupled plasma optical emission spectrometry Published on.2018-11-13 2019-03-01 Implementation Ministry of Ecology and Environment released i directory Foreword.ii 1 Scope..1 2 Normative references..1 3 method principle..1 4 Interference and elimination.1 5 reagents and materials. 2 6 instruments and equipment.4 7 samples.4 8 Analysis steps..5 9 Calculation and representation of results..6 10 Precision and Accuracy 8 11 Quality Assurance and Quality Control.8 12 Waste treatment 9 13 Notes 9 Appendix A (Normative Appendix) Method Detection Limit and Lower Measurement Limit.10 Appendix B (informative) Interference between analysis lines and coexisting elements.11 Appendix C (informative) The precision and accuracy of the method..12

Foreword

To implement the "Environmental Protection Law of the People's Republic of China", protect the ecological environment, protect human health, regulate soil and sink This standard is established for the determination of inorganic elements in the stock. This standard specifies the determination of manganese, strontium, vanadium, niobium, titanium, calcium, magnesium, iron, aluminum, potassium and silicon in soils and sediments. Alkali-melting-inductively coupled plasma optical emission spectroscopy of various elements. Appendix A of this standard is a normative appendix, and Appendix B~Appendix C is an informative appendix. This standard is the first release. This standard is formulated by the Department of Eco-Environmental Monitoring, the Department of Regulation and Standards of the Ministry of Ecology and Environment. This standard was drafted. Jilin Province Environmental Monitoring Center Station. This standard is verified by. Changchun Mining Resources Supervision and Inspection Center of Ministry of Land and Resources, Jilin University School of Chemistry, Jilin Inspection and Quarantine Technology Center of Entry Inspection and Quarantine Bureau, Harbin Environmental Monitoring Center Station, Tianjin Ecological Environment Monitoring Center and Guangdong Environmental Monitoring Center. This standard is approved by the Ministry of Ecology and Environment on November 13,.2018. This standard has been implemented since March 1,.2019. This standard is explained by the Ministry of Ecology and Environment. 1 Determination of 11 elements of soil and sediments - Alkali fusion-inductively coupled plasma Emission spectroscopy Warning. The nitric acid and hydrochloric acid used in the experiment are highly oxidizing, strong irritating and corrosive, and the solution is prepared before the sample. The treatment should be carried out in a fume hood, and care should be taken when wearing protective equipment to avoid inhalation of the respiratory tract or direct contact with the skin. And clothing.

1 Scope of application

This standard specifies alkali fusion-inductively coupled plasma optical emission spectrometry for the determination of 11 elements in soils and sediments. This standard applies to soils and sediments manganese (Mn), barium (Ba), vanadium (V), antimony (Sr), titanium (Ti), calcium (Ca), Determination of 11 elements such as magnesium (Mg), iron (Fe), aluminum (Al), potassium (K), and silicon (Si). When the sample volume is 0.2 g and the volume is 500 ml, manganese (Mn), barium (Ba), vanadium (V), strontium (Sr) and The detection limit of five metal elements of titanium (Ti) is 0.01 g/kg to 0.02 g/kg, and the lower limit of determination is 0.04 g/kg to 0.08 g/kg; Calcium (calculated as CaO), magnesium (calculated as MgO), iron (calculated as Fe2O3), aluminum (calculated as Al2O3), potassium (calculated as K2O) The detection limit of the six elemental oxides of silicon (as SiO2) is 0.01% to 0.07%, and the lower limit of determination is 0.04% to 0.28%. See Appendix A for details.

2 Normative references

This standard refers to the following documents or their terms. For undated references, the valid version applies to this standard. GB 17378.3 Marine monitoring specification Part 3. Sample collection, storage and transport GB 17378.5 Marine monitoring specification Part 5. Sediment analysis HJ 494 Water Quality Sampling Technical Guidance HJ 613 Determination of dry matter and moisture in soils - Gravimetric method HJ/T 166 Technical Specifications for Soil Environmental Monitoring

3 Principle of the method

The sample is melted with an alkaline flux, and the melt is dissolved by acid and injected into an inductively coupled plasma optical emission spectrometer. The characteristic line is vaporized, ionized, excited and radiated in the plasma torch. In a certain concentration range, its characteristic line is strong Degree is proportional to the concentration of the element.

4 interference and elimination

4.1 Spectral interference Spectral interference mainly includes continuous background interference and spectral line overlap interference. A common method of correcting spectral interference is background subtraction. 2 method (determination of the location and method of deducting the background according to the single element test) and the interference coefficient deduction method. When there is single element interference, The ' can be determined at the analytical elemental wavelength by formulating a series of solutions of known interfering element content, according to the formula (1) Find the interference coefficient %00%00. tK   )'(  (1) Where. %00%00--interference coefficient; ' - the concentration of the interfering element plus the analytical element measured at the wavelength of the analytical element, mg/L;  - the concentration of the analytical element, mg/L; T -- concentration of interfering elements, mg/L. The interference coefficients measured by different instruments will be different. The interference of coexisting elements at the wavelength of the analysis element is shown in Appendix B. 4.2 Non-spectral interference Non-spectral interference mainly includes chemical interference, physical interference, and solvent-free interference. The disturbances may coexist, whether they are compensated and corrected, and are related to the concentration of interfering elements in the sample. When the sample contains a lot When the soluble salt or sample is too acidic, it will interfere with the measurement. Diluted samples can be used (but the content of the elements to be tested should be guaranteed) Above the lower limit of determination), internal standard method, optimized instrument conditions and matrix matching method (preparation of the standard similar to the matrix of the sample to be tested) Measures such as quasi-solutions eliminate and reduce the above interference.

5 reagents and materials

Unless otherwise stated, the analysis uses a pure grade reagent that meets national standards, and the experimental water is a newly prepared deionized reagent. water. 5.1 Hydrochloric acid. ρ(HCl) = 1.19 g/ml. 5.2 Nitric acid. ρ(HNO3) = 1.42 g/ml. 5.3 Sodium carbonate (Na2CO3). 5.4 Lithium tetraborate (Li2B4O7). 5.5 Lithium metaborate (LiBO2). 5.6 Nitric acid solution. 1 1. 5.7 Nitric acid solution. 14. 5.8 Nitric acid solution. 1 99. 5.9 Hydrochloric acid solution. 1 1. 5.10 Mixed solution of nitric acid-hydrochloric acid. 14. 5.11 Matrix matching solution. Weigh 2.0 g sodium carbonate (5.3), 0.2 g lithium tetraborate (5.4) and 0.8 g lithium metaborate (5.5) into a beaker. After water wetting, add 64 ml of hydrochloric acid (5.1) and 16 ml of nitric acid (5.2) to dissolve. After the solution is cooled, dilute to 1 L with water. 5.12 Single element standard stock solution. 5.12.1 Manganese standard stock solution. ρ≈1000 mg/L. Weigh 1.00 g (accurate to 0.1 mg) of manganese metal (spectrum pure) and dissolve it with 30 ml of hydrochloric acid solution (5.9). 3 After cooling, dilute to 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.2 钡 standard stock solution. ρ ≈ 1000 mg/L. Weigh 1.52 g (accurate to 0.1 mg) of anhydrous barium chloride (BaCl2, dried at 250 ° C for 2 h) with 20 ml of nitric acid solution (5.6) Dissolve and bring up to 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.3 Standard stock solution of vanadium. ρ≈1000 mg/L. 2.30 g (accurate to 0.1 mg) of ammonium vanadate (NH4VO3) was weighed and heated to complete dissolution with 10 ml of nitric acid (5.2). Make up to 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.4 锶 standard stock solution. ρ ≈ 1000 mg/L. Weigh 1.68 g (accurate to 0.1 mg) of cesium carbonate (SrCO3, dried at 105 ° C for 1 h) with 60 ml of hydrochloric acid solution (5.9) Dissolve and boil, cool to a volume of 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.5 Titanium standard stock solution. ρ≈1000 mg/L. Weigh 1.00 g (accurate to 0.1 mg) of titanium metal (spectrum pure) and dissolve it with 100 ml of hydrochloric acid solution (5.9). After cooling, make up to 1 L with hydrochloric acid solution (5.9). Commercially available certified standard solutions can also be purchased directly. 5.12.6 Calcium standard stock solution. ρ≈1000 mg/L. Weigh 2.50 g (accurate to 0.1 mg) of calcium carbonate (CaCO3, dried at 110 ° C for 1 h), dissolve in 20 ml of water, add Enter 10 ml of hydrochloric acid (5.1) until completely dissolved, boil to remove CO2, and cool to a volume of 1 L with water. You can also buy the city directly A certified standard solution is sold. 5.12.7 Magnesium standard stock solution. ρ≈1000 mg/L. Weigh 1.00 g (accurate to 0.1 mg) of magnesium metal (spectrum pure), add 30 ml of water, and slowly add 30 ml of hydrochloric acid (5.1) To complete dissolution, boil, cool to a volume of 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.8 Iron standard stock solution. ρ≈1000 mg/L. Weigh 1.00 g (accurate to 0.1 mg) of metallic iron (spectrum pure), dissolve it with 150 ml of hydrochloric acid solution (5.9), and cool Make up to 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.9 Aluminum standard stock solution. ρ≈1000 mg/L. Weigh 1.00 g (accurate to 0.1 mg) of aluminum metal (spectrum pure) and dissolve it with 150 ml of hydrochloric acid solution (5.9). Boil, cool to a volume of 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.12.10 Potassium standard stock solution. ρ≈1000 mg/L. Weigh 1.91 g (accurate to 0.1 mg) of potassium chloride (KCl, burn at 400 ° C ~ 450 ° C until no cracking sound), dissolved in water Untie and fix to 1 L. Commercially available certified standard solutions can also be purchased directly. 5.12.11 Silicon standard stock solution. ρ≈1000 mg/L. Weigh 6.34 g (accurate to 0.1 mg) of ammonium hexafluorosilicate [(NH4)2SiF6] and use.200 ml hydrochloric acid solution (5.9) to lower temperature. Heat to complete dissolution, cool to 1 L with water. Commercially available certified standard solutions can also be purchased directly. 5.13 Single element standard use solution. The unitary standard stock solution (5.12) was separately diluted and prepared with a nitric acid solution (5.8). Among them Mn, Ba, V, The concentration of Sr element is 10 mg/L; the concentration of Ti, Ca, Mg and K is 100 mg/L; the concentration of Al and Fe is.200 mg/L. 5.14 Multi-element mixing standard use solution. According to the nature of the standard solution and the inter-element interference, the unitary standard stock solution (5.12) is used to prepare or directly Purchase a commercially available certified standard solution. The multi-element mixing standard use liquid grouping and concentration are shown in Table 1. 4 Table 1 Multi-element mixed standard use liquid grouping and reference concentration table Grouping elements 1 Mn (10 mg/L), Ba (10 mg/L), V (10 mg/L), Sr (10 mg/L) Ti (100 mg/L), Ca (100 mg/L), Mg (100 mg/L), Fe (200 mg/L), Al (200 mg/L), K (100 mg/L) 3 Si (1000 mg/L) 5.15 Internal standard stock solution. ρ=1000 mg/L. Rh (Rh) is selected as the internal standard element, and other internal standard elements can be selected after verification. Purchase a commercially available certified standard solution. 5.16 Argon. purity ≥ 99.999%.

6 Instruments and equipment

6.1 Inductively Coupled Plasma Emission Spectrometer. High salt tolerant atomizer with two-way observation. 6.2 Oven. The temperature is controllable. 6.3 Analytical balance. The sensitivity is 0.0001 g. 6.4 Muffle furnace. The maximum temperature can reach 1200 °C. 6.5 Platinum 坩埚. 30 ml. 6.6 Nylon sieve. 0.15 mm (100 mesh), 0.096 mm (160 mesh). 6.7 Common instruments and equipment used in general laboratories.

7 samples

7.1 Sample collection and preservation Collect and store soil samples in accordance with the relevant provisions of HJ/T 166; in accordance with the relevant provisions of GB 17378.3 Collection and storage of marine sediment samples; collection of water sediment samples in accordance with the relevant provisions of HJ 494. 7.2 Preparation of samples Remove foreign matter (branches, leaves, stones, etc.) from the sample, according to the requirements of HJ/T 166 and GB 17378.5 The collected samples were air-dried, coarsely ground, finely ground, and passed through a nylon screen (6.6) for use. 7.3 Determination of moisture The moisture was measured while preparing the sample. The determination of dry matter content of soil samples is carried out according to HJ 613, sinking The moisture content of the sample was measured in accordance with GB 17378.5. 7.4 Preparation of samples First add a small amount of sodium carbonate (5.3) bottom at the bottom of platinum (6.5), weigh 1.0 g sodium carbonate (5.3), 0.1 g lithium tetraborate (5.4) and 0.4 g lithium metaborate (5.5), properly mixed to form a flux, and then add about 2/3 of the flux and 0.2 g (accurate to 0.1 mg) of the sample (7.2), and finally put the remaining flux onto the surface of the mixture. Platinum 5埚 was placed in a muffle furnace (6.4), heated to 1000 ° C, held for 30 min, and the heating was stopped. After about 5 minutes, use the jaw clamp Platinum crucible is placed upright in a 500 ml beaker containing 100 ml of water. After the melt is cracked, remove the crucible and Add water to the crucible until there is no melt. When the melt is separated from the crucible, transfer the exfoliated melt to a 250 ml beaker. in. Take 40 ml of a mixed solution of nitric acid-hydrochloric acid (5.10), first rinse the wall with a little nitric acid-hydrochloric acid mixed solution. Precipitate, transfer the eluent into the beaker, rinse the mash with water, and finally add the remaining nitric acid-hydrochloric acid mixture solution to the beaker. Dissolve all the melt, transfer the solution in the beaker to a 500 ml volumetric flask, and bring up to the mark with water to be tested. 7.5 Preparation of blank samples The blank sample was prepared in the same manner as in the preparation of the sample (7.4) without adding a sample.

8 Analysis steps

8.1 Instrument Reference Conditions The best test conditions for different types of instruments are different, and the test conditions are optimized according to the specifications of the instrument. Instrument reference test Conditions are shown in Table 2. Table 2 Instrument reference test conditions Serial number element wavelength (nm) power (W) Cooling gas carrier gas assist gas integration time (s) Internal standard (L/min) Wavelength 343.489 nm 1 Mn 257.610 1200 15 0.8 0.2 1~5 2 Ba 455.403 1200 15 0.8 0.2 1~5 Must be used 3 V 292.402 1200 15 0.8 0.2 1~5 Must be used 4 Sr 460.733 1200 15 0.8 0.2 1~5 Must be used 5 Ti 334.940 1200 15 0.8 0.2 1~5 Must 6 Ca 315.887 1200 15 0.8 0.2 1~5 7 Mg 285.213 1200 15 0.8 0.2 1~5 8 Fe 238.204 1200 15 0.8 0.2 1~5 9 Al 396.153 1200 15 0.8 0.2 1~5 10 K 766.490 1200 15 0.8 0.2 1~5 11 Si 251.611 1500 15 0.5 1.0 1~10 Must be used 8.2 Establishment of the standard curve Transfer a certain volume of the standard solution to a 100 ml volumetric flask and dilute to volume with a matrix matching solution (5.11). A standard line of solutions that can cover at least 5 concentration points of the sample concentration range. Standard series of target elements The reference concentration range of the solution is shown in Table 3. The internal standard stock solution (5.15) can be added directly to the standard series or automatically via a peristaltic pump. Internal standard element The concentration in the 6 standard series is 2.50 mg/L to 5.00 mg/L. Inject from low to high concentrations in sequence, according to the instrument reference test Test conditions (8.1) measure the emission intensity, with the target element mass concentration in the standard series solution as the abscissa, with the target element The ratio of the emission intensity to the internal standard is the ordinate, and a standard curve of the target element is established. Table 3 11 element standard solution series reference concentration Element standard solution standard solution concentration (mg/L) Internal standard concentration (mg/L) Mn, Ba, V, Sr 5.13 or 5.14 0.00 0.10 0.20 0.50 0.80 1.00 2.50 ~ 5.00 Ti 5.13 or 5.14 0.00 1.00 2.00 5.00 8.00 10.0 2.50 ~5.00 Ca, Mg, K 5.13 or 5.14 0.00 5.00 10.0 15.0 20.0 30.0 2.50 ~5.00 Fe, Al 5.13 or 5.14 0.00 10.0 20.0 30.0 40.0 50.0 2.50 ~ 5.00 Si 5.12.11 or 5.14 0.00 10.0 20.0 50.0 80.0 100 2.50 ~5.00 8.3 Sample determination The measurement of the sample (7.4) was carried out in accordance with the same instrumental analysis conditions as the standard curve establishment (8.2). 8.4 Blank test The blank sample (7.5) was measured in accordance with the same instrumental analysis conditions as the sample measurement (8.3).

9 Calculation and representation of results

9.1 Calculation of results 9.1.1 Soil samples The content of elements manganese (Mn), barium (Ba), vanadium (V), strontium (Sr) and titanium (Ti) in soil samples is 1w (g/kg), Calculated according to formula (2); calcium (calculated as CaO), magnesium (calculated as MgO), iron (calculated as Fe2O3), aluminum (as Al2O3) The content of potassium (calculated as K2O) and silicon (calculated as SiO2) is 2w (%), and is calculated according to formula (3). -31 0 1 Dm Mw     (2) Where. 1w - the content of the element to be tested in the sample, g/kg; Ρ1 - the mass concentration of the element to be tested in the sample, mg/L; Ρ0--the mass concentration of the element to be tested in the blank sample, mg/L; 1V--the volumetric volume of the sample, ml; 1m -- weigh the sample, g; w dm--the dry matter content of the soil sample, %. twenty one Dm VM Mw M        (3) In the formula. 2w - the content of the element to be tested in the sample, %; Ρ1 - the mass concentration of the element to be tested in the sample, mg/L; Ρ0--the mass concentration of the element to be tested in the blank sample, mg/L; 2V - the volumetric volume of the sample, ml; M2--the molar mass of the element oxide to be tested; 2m -- weigh the sample, g; w dm--the dry matter content in the soil sample, %; M1--molar mass of the element to be tested. 9.1.2 Sediment samples The contents of the elements manganese (Mn), barium (Ba), vanadium (V), strontium (Sr) and titanium (Ti) in the sediment samples are 3w (g/kg), Calculated according to formula (4); calcium (calculated as CaO), magnesium (calculated as MgO), iron (calculated as Fe2O3), aluminum (as Al2O3) The content of potassium (calculated as K2O) and silicon (calculated as SiO2) is 4w (%), and is calculated according to formula (5). -31 0 3 (1 ) 2H O Mw      (4) Where. 3w - the content of the element to be tested in the sample, g/kg; Ρ1 - the mass concentration of the element to be tested in the sample, mg/L; Ρ0--the mass concentration of the element to be tested in the blank sample, mg/L; 3V - the volumetric volume of the sample, ml; 3m -- weigh the sample, g; w H2O - moisture content of the sediment sample, %. (1 ) 2H O VM Mw M         (5) Where. 4w - the content of the element to be tested in the sample, %; Ρ1 - the mass concentration of the element to be tested in the sample, mg/L; Ρ0--the mass concentration of the element to be tested in the blank sample, mg/L; 4V - the volumetric volume of the sample, ml; M2--the molar mass of the element oxide to be tested; 4m -- weigh the sample, g; w H2O--the moisture content of the sediment sample, %; M1--molar mass of the element to be tested. 9.2 Results representation The number of decimal places of the measurement is consistent with the method detection limit, and up to three significant digits are reserved. 810 precision and accuracy 10.1 Precision Six laboratories performed six replicate measurements on two soils and two sediment-containing standard materials containing 11 elements. The relative standard deviations in the experimental room range from 0.18% to 22%, 0.32% to 17%, 0.48% to 9.5%, and 0.50% to 7.6%, respectively; The relative standard deviations between laboratories range from 1.5% to 14%, 1.2% to 5.5%, 1.9% to 5.8%, and 1.2% to 4.9%, respectively; The repeatability limits of manganese (Mn), barium (Ba), vanadium (V), strontium (Sr) and titanium (Ti) are 0.02-0.69 g/kg and 0.02-, respectively. 0.32 g/kg, 0.03 to 0.63 g/kg, and 0.02 g to 0.54 g/kg; the reproducibility limits are 0.03 to 0.88 g/kg and 0.02 to 0.35 g/kg, respectively. 0.03～0.66 g/kg and 0.02～0.62 g/kg; calcium (calculated as CaO), magnesium (calculated as MgO), iron (calculated as Fe2O3), aluminum The repeatability limits (in terms of Al2O3), potassium (as K2O), and silicon (as SiO2) are 0.12% to 5.6%, 0.15%, respectively. 9.0%, 0.22% to 7.4%, and 0.16% to 6.7%; the reproducibility limits are 0.13% to 6.7%, 0.16% to 10%, and 0.34%, respectively. 8.4% and 0.23% to 7.8%. For the method precision results, see Table C.1 and Table C.2 in Appendix C. 10.2 Accuracy Six laboratories performed six replicate measurements on two soils and two sediment-containing standard materials containing 11 elements. The relative errors are -0.43% to 8.3%, -2.4% to 2.1%, -0.29% to 4.1%, and -2.3% to 4.2%, respectively. The values are (-0.43±3.0)% to (8.3±30)%, (-2.4±6.4)% to (2.1±3.6)%, and (-0.29±4.0)%. (4.1 ± 4.0)% and (-2.3 ± 5.4)% to (4.2 ± 5.2)%. Six laboratories performed spiked analysis on soil and sediment samples containing 10 elements, respectively. The recoveries of spiked samples ranged from 70.0% to 119%, and the final recoveries of spiked samples were (79.7±2.0)%～(96.7± 17.8)%; the recoveries of the actual samples in the sediment ranged from 70.2% to 116%, and the final value of the spiked recovery was (82.1± 1.0)%~(95.9±14.5)%. For the method accuracy results, see Table C.3 to Table C.6 in Appendix C. 11 Quality Assurance and Quality Control 11.1 Blank test A blank test shall be performed for every 10 samples or batches (less than 10 samples/batch), and the blank value of the measured elements shall be Below the lower limit of the method determination. 11.2 Calibration A standard curve should be established for each analysis. The correlation coefficient of the standard curve should be ≥0.995. A standard curve intermediate concentration point standard solution should be analyzed for every 20 samples or batches (less than 20 samples/batch). The relative error between the measured result and the concentration value of the point should be within ±10%, otherwise the standard curve should be redrawn. 11.3 Parallel samples Analyze at least one parallel sample for every 20 samples or batches (less than 20 samples/batch). The relative deviation of 9 should be ≤ 35%. 11.4 Accuracy 11.4.1 Use of certified reference materials Analyze at least one certified standard of soil or sediment for every 20 samples or batches (less than 20 samples/batch), The accuracy requirements for the measured values of certified reference materials are shown in Table 4. Table 4 Accuracy requirements for certified reference materials Content range Accuracy ∆lg%00(%00th) = |lg%00%00 − lg%00%00| Within ...

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