阅读说明：本技术 一种土壤易溶盐中Cl-、SO42-、NO3-的快速检测方法 (Cl in soil soluble salt-、SO42-、NO3-Rapid detection method of ) 是由 于梦翌 耿楠 石丽华 李鹏 田野 于 2021-07-21 设计创作，主要内容包括：本发明公开了一种土壤易溶盐中Cl～(-)、SO4～(2-)、NO～(3-)的快速检测方法,包括以下步骤：S1、准备实验试剂、材料以及实验仪器设备；S2、采集、保存土壤样品；S3、制备实验样品；S4、进行离子色谱分析及标准曲线绘制；S5、按照与绘制标准曲线相同的色谱条件和步骤,进行试样及空白样品的测定；S6、计算样品中无机阴离子Cl～(-)、NO～(3-)、SO4～(2-)的质量浓度,本发明能够大大提高测试效率,减少实验误差,快速方便、灵敏度高、选择性好,完全能够满足普通土壤和盐碱地土壤中的阴离子测定,一次性能够测量三种阴离子,提高效率。(The invention discloses Cl in soil soluble salt ‑ 、SO4 2‑ 、NO 3‑ The rapid detection method comprises the following steps: s1, preparing experimental reagents, materials and experimental instrument equipment; s2, collecting and storing a soil sample; s3, preparing an experimental sample; s4, performing ion chromatographic analysis and standard curve drawing; s5, measuring the sample and the blank sample according to the chromatographic conditions and steps which are the same as those of the standard curve drawing; s6, calculating inorganic anion Cl in the sample ‑ 、NO 3‑ 、SO4 2‑ The method can greatly improve the testing efficiency, reduce experimental errors, is quick and convenient, has high sensitivity and good selectivity, can completely meet the requirement of anion determination in common soil and saline-alkali soil, can measure three anions at one time, and improves the efficiency.)

1. Cl in soil soluble salt^-、SO4^2-、NO^3-The rapid detection method is characterized by comprising the following steps:

s1, preparing experimental reagents, materials and experimental instrument equipment;

s2, collecting and storing a soil sample;

s3, preparing an experimental sample;

s4, performing ion chromatographic analysis and standard curve drawing;

s5, measuring the sample and the blank sample according to the chromatographic conditions and steps which are the same as those of the standard curve drawing;

s6, calculating inorganic anion Cl in the sample^-、NO^3-、SO4^2-Mass concentration of (2).

2. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The method for the rapid detection of (2),it is characterized in that the experimental reagents and materials in the step S1 include: sodium chloride, potassium nitrate, anhydrous sodium sulfate, sodium carbonate, sodium bicarbonate, sodium hydroxide, chloride ion standard storage solution, nitrate radical standard storage solution, sulfate radical standard storage solution, mixed standard use solution, carbonate leacheate I, carbonate leacheate II, hydroxide leacheate, potassium hydroxide leacheate and sodium hydroxide leacheate.

3. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The rapid detection method of (5), wherein the laboratory instruments and devices in step S1 include: ion chromatograph, chromatographic column, anion suppressor, conductivity detector, air-extracting filter, disposable water system microporous filter membrane syringe filter, disposable injector and pretreatment column.

4. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The method for rapid detection according to (1), wherein the step of preparing the test sample in step S3 includes:

s3-1, filtering the clean leachate which does not contain interfering substances such as hydrophobic compounds, heavy metals or transition metal ions and the like by an air extraction filtering device, and directly feeding a sample; or a disposable injector with a water system microporous filter membrane cylinder filter is used for sample injection; for complex leachate samples containing interfering substances, the samples are effectively removed by using corresponding pretreatment columns and then injected.

S3-2 preparation of blank sample

A laboratory blank was prepared by the same procedure as for the preparation of the test sample, with the experimental water replacing the sample.

5. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The fast detection method of (2), wherein the drawing of the standard curve in step S4 includes: determining a proper standard series concentration range according to the concentration of a sample to be detected, and preparing 6 mixed standard series with different concentrations; according to the mixed standard systemSequentially injecting the column concentrations into an ion chromatograph from low to high, and recording peak areas or peak heights; and drawing a standard curve by taking the mass concentration of each ion as an abscissa and taking the peak area or peak height as an ordinate.

6. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The rapid detection method according to (9), wherein the measurement of the sample in step S5 includes: according to the same chromatographic conditions and steps as those for drawing a standard curve, a sample is injected into an ion chromatograph to determine the anion concentration, and the retention time is qualitative and the instrument response value is quantitative.

The determination of the blank sample included: the blank sample is injected into an ion chromatograph to determine the anion concentration according to the same chromatographic conditions and procedures as the determination of the sample, and is qualitative by retention time and quantitative by instrument response value.

7. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The fast detection method of (2), wherein the calculating step of step S6 calculates according to the formula (1):

in the above formula: rho is the mass concentration of anions in the sample, mg/L;

h is the peak area (or peak height) of the anion in the sample;

h₀peak area (or peak height) for the anion in the laboratory blank;

a is the intercept of the regression equation;

b is the slope of the regression equation;

f is the dilution factor of the sample;

when the content of the sample is less than 1mg/L, the result is retained to three decimal places; when the sample content is greater than or equal to 1mg/L, the result retains three significant digits.

8. The soil soluble salt of claim 1 wherein Cl is in the soil soluble salt^-、SO4^2-、NO^3-The rapid detection method of (2) is characterized by further comprising:

s7 blank test

At least 2 laboratory blank tests should be carried out on each batch (less than or equal to 20) of samples, and the blank test result should be lower than the detection limit of the method; otherwise, the reason should be found out, and the sample cannot be measured until the sample is qualified after reanalysis;

s8 correlation test

The correlation coefficient of the standard curve is more than or equal to 0.995, otherwise, the standard curve is drawn again;

s9, continuous calibration

For each batch (less than or equal to 20) of samples, a standard solution with the concentration of the middle point of the standard curve is analyzed, and the relative error between the measured result and the concentration of the middle point of the standard curve is less than or equal to 10 percent; otherwise, the standard curve is drawn again;

s10, precision control

At least 10% of the replicates per batch (. ltoreq.20) should be tested, and at least one replicate should be tested when the number of samples is less than 10. The relative deviation of the parallel double-sample determination result is less than or equal to 10 percent;

s11 accuracy control

At least 1 standard adding recovery rate measurement should be carried out on each batch (less than or equal to 20) of samples, and the standard adding recovery rate of the actual samples should be controlled between 80% and 120%;

and S12, waste treatment.

Technical Field

The invention relates to the field of soil detection, in particular to Cl in soil soluble salt^-、SO4^2-、NO^3-The rapid detection method of (1).

Background

Soil salinization is a strategic problem of drought sustainable development and improvement of environmental quality. The saline soil in China has large area and wide distribution, and can be the best of the world. According to statistics, the salinization area in cultivated land in China reaches 9.2 multiplied by 10hm, and accounts for 6.62 percent of the cultivated land area in China. The problem of soil salinization and the problem of secondary soil salinization caused by irrigation seriously restrict the further development of agriculture in salinized areas and are also important factors influencing the stability of ecological environment. Soluble salts in saline soil generally exist in the form of ions in solution, and damage to plants due to too high content of salt-based ions is called salt damage. These ions, at high concentrations, can produce secondary damaging effects in addition to direct damage.

Excessive chloride ion can inhibit the plant's absorption of HPO42-, and foreign scholars observe that chloride ion accumulates in potato leaves and can interfere with photosynthesis. Chloride poisons to plants manifest as chlorine deficiency in the early stages, with dry and browned leaf tips. After the initial burn occurs, the affected tissues need to be further enlarged, can be prevented from extending to 1/2-1/3 parts of the leaf surface along the leaf edge, and sometimes the whole page can become brown and have necrosis symptoms. In severe cases, the tips of fallen leaves, stems and small branches can have obvious blight and therefore die. The existing detection method for chloride ions in soil has few monitoring point positions and narrow coverage area, so the method has poor representativeness, wastes time and labor, cannot reflect the content of chloride ions in large-area salinized soil, and cannot meet the requirement of large-area monitoring.

The high-concentration sulfate ions have obvious toxicity, and are reported on crops such as flax, tomatoes, cotton and the like. Analysis of the leaves of peas, peach trees, orchard grass and cotton by Gaoqi, Wallefu and Haerward et al revealed that the leaf tissue of plants grown in soil dominated by sulphate contained significantly less calcium, while sodium and potassium were significantly more contained. It follows that high concentrations of sulphate in the soil significantly limit the mobility of calcium ions and prevent the absorption of calcium ions by plants.

Due to the use of a large amount of chemical nitrogen fertilizers, nitrate type secondary salinized soil not only brings direct high-salt harm to the growth of crops, but also unbalance beneficial microbial flora of the soil, and even loses the production capacity of the soil in serious cases.

In newly issued GB/T50123-2019 geotechnical test method Standard, soil is subjected to salt solubility analysis, and anions still adopt an ultraviolet spectrophotometry method and a chemical titration method, so that the method is low in efficiency and large in error.

Disclosure of Invention

In order to solve the technical problems, the technical scheme provided by the invention is as follows: cl in soil soluble salt^-、SO4^2-、NO^3-The rapid detection method comprises the following steps:

s1, preparing experimental reagents, materials and experimental instrument equipment;

s2, collecting and storing a soil sample;

s3, preparing an experimental sample;

s4, performing ion chromatographic analysis and standard curve drawing;

s5, measuring the sample and the blank sample according to the chromatographic conditions and steps which are the same as those of the standard curve drawing;

s6, calculating inorganic anion Cl in the sample^-、NO^3-、SO4^2-Mass concentration of (2).

Preferably, the experimental reagents and materials in step S1 include: sodium chloride, potassium nitrate, anhydrous sodium sulfate, sodium carbonate, sodium bicarbonate, sodium hydroxide, a chloride ion standard storage solution, a nitrate radical standard storage solution, a sulfate radical standard storage solution, a mixed standard use solution, a carbonate leacheate I, a carbonate leacheate II, a hydroxide leacheate, a potassium hydroxide leacheate and a sodium hydroxide leacheate.

Preferably, the laboratory instrument apparatus in step S1 includes: ion chromatograph, chromatographic column, anion suppressor, conductivity detector, air pumping filter, disposable water system microporous filter membrane syringe filter, disposable injector and pretreatment column.

Preferably, the preparing the experimental sample in step S3 includes:

s3-1, filtering the clean leachate which does not contain interfering substances such as hydrophobic compounds, heavy metals or transition metal ions and the like by an air extraction filtering device, and directly feeding a sample; or a disposable injector with a water system microporous filter membrane cylinder filter is used for sample injection; for complex leaching solution samples containing interfering substances, a corresponding pretreatment column is required to be used for effectively removing the samples and then injecting samples.

S3-2 preparation of blank sample

A laboratory blank was prepared by the same procedure as for the preparation of the test sample, with the experimental water replacing the sample.

Preferably, the standard curve drawing in step S4 includes: determining a proper standard series concentration range according to the concentration of a sample to be detected, and preparing 6 mixed standard series with different concentrations; injecting the mixed standard series of concentrations into an ion chromatograph from low to high in sequence, and recording peak areas or peak heights; and drawing a standard curve by taking the mass concentration of each ion as an abscissa and taking the peak area or peak height as an ordinate.

Preferably, the determination of the sample in step S5 includes: according to the same chromatographic conditions and steps as those for drawing a standard curve, a sample is injected into an ion chromatograph to determine the anion concentration, and the retention time is qualitative and the instrument response value is quantitative.

The determination of the blank sample included: the blank sample is injected into an ion chromatograph to determine the anion concentration according to the same chromatographic conditions and procedures as the determination of the sample, and is qualitative by retention time and quantitative by instrument response value.

Preferably, the calculating step of step S6 is calculated according to formula (1):

in the above formula: rho is the mass concentration of anions in the sample, mg/L;

h is the peak area (or peak height) of the anion in the sample;

h₀peak area (or peak height) for the anion in the laboratory blank;

a is the intercept of the regression equation;

b is the slope of the regression equation;

f is the dilution factor of the sample;

when the content of the sample is less than 1mg/L, the result is retained to three decimal places; when the content of the sample is more than or equal to 1mg/L, the result retains three significant figures.

Preferably, it is also necessary to perform:

s7 blank test

At least 2 laboratory blank tests should be carried out on each batch (less than or equal to 20) of samples, and the blank test result should be lower than the detection limit of the method; otherwise, the reason should be found out, and the sample cannot be measured until the sample is qualified after reanalysis;

s8 correlation test

The correlation coefficient of the standard curve is more than or equal to 0.995, otherwise, the standard curve is drawn again;

s9, continuous calibration

For each batch (less than or equal to 20) of samples, a standard solution with the concentration of the middle point of the standard curve is analyzed, and the relative error between the measured result and the concentration of the middle point of the standard curve is less than or equal to 10 percent; otherwise, the standard curve is drawn again;

s10, precision control

At least 10% of the replicates per batch (. ltoreq.20) should be tested, and at least one replicate should be tested when the number of samples is less than 10. The relative deviation of the parallel double-sample determination result is less than or equal to 10 percent;

s11 accuracy control

At least 1 standard adding recovery rate measurement should be carried out on each batch (less than or equal to 20) of samples, and the standard adding recovery rate of the actual samples should be controlled between 80% and 120%;

and S12, waste treatment.

After the scheme is adopted, the invention has the following advantages: the invention adopts ion chromatography to rapidly determine Cl in soil soluble salt^-、SO₄ ^2-、 NO₃ ^-Three anions have wide measuring linear range according to the characteristics of soluble salt in soil and the characteristics of instruments and equipment, can completely meet the requirement of measuring the anions in common soil and saline-alkali soil, does not need dilution in the measuring process, can greatly improve the testing efficiency, reduces the experimental error, is quick and convenient, has high sensitivity and good selectivity, and can completely fill the measuring rangeThe method is sufficient for measuring the anions in common soil and saline-alkali soil, can measure three anions at one time, and improves the efficiency.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments.

Examples

A method for rapidly detecting Cl-, SO 42-and NO 3-in soil soluble salt is characterized in that,

s1, preparing experimental reagents, materials and experimental instrument equipment;

wherein the experimental reagent and the materials comprise:

(1) sodium chloride (NaCl): before use, the mixture is dried at 105 +/-5 ℃ and then stored in a drier.

(2) Potassium nitrate (KNO 3): the high-grade pure tea is dried at 105 +/-5 ℃ to constant weight before use and then stored in a dryer.

(3) Anhydrous sodium sulfate (Na2SO 4): the high-grade pure tea is dried at 105 +/-5 ℃ to constant weight before use and then stored in a dryer.

(4) Sodium carbonate (Na2CO 3): before use, the mixture is dried at 105 +/-5 ℃ and then stored in a drier.

(5) Sodium bicarbonate (NaHCO 3): the product should be placed in a dryer to be equilibrated for 24h before use.

(6) Sodium hydroxide (NaOH): and 4, high-grade purity.

(7) Chloride ion standard stock solution: rho (Cl-) -1000 mg/L; accurately weighing 1.6485g of sodium chloride, dissolving in a proper amount of water, transferring the total amount into a 1000ml volumetric flask, diluting with water to a constant volume to a marked line, and mixing uniformly; transferring into polyethylene bottle, refrigerating at below 4 deg.C, protecting from light, sealing, and storing for 6 months. Commercially available certified standard materials may also be purchased.

(8) Nitrate standard stock solution: ρ (NO3-) -1000 mg/L; accurately weighing 1.6304g of potassium nitrate, dissolving in a proper amount of water, transferring the total amount into a 1000ml volumetric flask, diluting with water by 3, fixing the volume to the marked line, and uniformly mixing; transferring into polyethylene bottle, refrigerating at below 4 deg.C, protecting from light, sealing, and storing for 6 months. Commercially available certified standard materials may also be purchased.

(9) Sulfate radical standard stock solution: ρ (SO42-) -1000 mg/L; accurately weighing 1.4792g of anhydrous sodium sulfate, dissolving in a proper amount of water, transferring the total amount into a 1000ml volumetric flask, diluting with water, fixing the volume to the marked line, and mixing uniformly; transferring into polyethylene bottle, refrigerating at below 4 deg.C, protecting from light, sealing, and storing for 6 months. Commercially available certified standard materials may also be purchased.

(10) Mixing standard use solution: 200.0ml of chloride ion standard storage solution, 100.0ml of nitrate radical standard storage solution and 200.0ml of sulfate radical standard storage solution are respectively transferred into a 1000ml volumetric flask, diluted by water to a constant volume to be marked and mixed evenly. The mixture was prepared as a standard solution containing 200mg/L Cl-, 100mg/L NO3-, and 200mg/L SO 42-.

(11) Carbonate leacheate I: c (Na2CO3) ═ 6.0mmol/L, c (NaHCO3) ═ 5.0 mmol/L. 1.2720g of sodium carbonate and 0.8400g of sodium bicarbonate are accurately weighed, respectively dissolved in a proper amount of water, the total amount is transferred into a 2000ml volumetric flask, diluted with water to a constant volume to be marked, and mixed evenly.

(12) Carbonate leacheate II: c (Na2CO3) ═ 3.2mmol/L, c (NaHCO3) ═ 1.0 mmol/L. 0.6784g of sodium carbonate and 0.1680g of sodium bicarbonate are accurately weighed, respectively dissolved in a proper amount of water, the total amount is transferred into a 2000ml volumetric flask, diluted with water to a constant volume to be marked, and mixed evenly.

(13) Hydroxide leacheate: automatically generated on-line by an instrument or manually prepared.

(14) Potassium hydroxide leacheate: generated on-line by an automatic electrolytic generator of leacheate.

(15) Sodium hydroxide leacheate: c (naoh) 100 mmol/L; weighing 100.0g of sodium hydroxide, adding 100ml of water, stirring until the sodium hydroxide is completely dissolved, standing in a polyethylene bottle for 24h to obtain a sodium hydroxide stock solution, refrigerating at the temperature below 4 ℃, keeping out of the sun, sealing and storing for 3 months; transferring 5.20ml of the sodium hydroxide stock solution into 1000ml of the sodium hydroxide stock solution, diluting with water to a constant volume to a marked line, mixing uniformly, and immediately transferring to a leaching solution bottle; nitrogen protection may be added to slow the alkaline leacheate from absorbing CO2 in the air and becoming ineffective.

The laboratory instrument apparatus comprises:

(1) ion chromatography: the analysis system consists of an ion chromatograph, operating software and required accessories.

(2) A chromatographic column: anion separation columns (polydivinylbenzene/ethylvinylbenzene/polyvinyl alcohol matrix, hydrophilic, high capacity chromatography columns with quaternary alkyl ammonium or alkanol ammonium functionality) and anion protection columns; 3 anions specified by the method can be measured by one-time sample injection, and the separation degree of peaks is not lower than 1.5.

(2) Anion suppressor:

(4) a conductivity detector:

(5) an air extraction and filtration device: is provided with an acetate fiber or polyethylene filter membrane with the aperture less than or equal to 0.45 mu m.

(6) Disposable water system microporous filter membrane syringe filter: the pore diameter is 0.45 μm.

(7) A disposable injector: 1ml to 10m

(8) Pre-treating the column: polystyrene-divinylbenzene-based RP column or silica gel-based bonded C18 column (hydrophobic compound removed); h-type or Na-type strong acid cation exchange column (for removing heavy metal and transition metal ions).

(9) Common laboratory instruments and equipment:

s2, collecting and storing a soil sample;

collecting samples according to the relevant regulations of GB/T50123-2019, preparing leachate, analyzing the collected samples as soon as possible, if the samples cannot be measured in time, filtering the samples by using an air-extracting and filtering device, and refrigerating the samples at the temperature of below 4 ℃ and keeping the samples away from light. The storage time and container material requirements for different ions to be tested are shown in the following table.

Name of ion	Material of container	Retention time
			Cl-	Hard glass bottle or polyethylene bottle	30 days
NO3-	Hard glass bottle or polyethylene bottle	7 days
			SO42-	Hard glass bottle or polyethylene bottle	30 days

S3, preparing an experimental sample;

the method comprises the following steps: s3-1, filtering the clean leachate which does not contain interfering substances such as hydrophobic compounds, heavy metals or transition metal ions and the like by an air extraction filtering device, and directly feeding a sample; or a disposable injector with a water system microporous filter membrane cylinder filter is used for sample injection; a complex leachate sample containing interfering substances needs to be effectively removed by a corresponding pretreatment column and then is subjected to sample injection.

S3-2 preparation of blank sample

A laboratory blank was prepared by the same procedure as for the preparation of the test sample, with the experimental water replacing the sample.

S4, performing ion chromatographic analysis and standard curve drawing;

the method comprises the following steps: determining a proper standard series concentration range according to the concentration of a sample to be detected, and preparing 6 mixed standard series with different concentrations; injecting the mixed standard series of concentrations into an ion chromatograph from low to high in sequence, and recording peak areas or peak heights; and (4) drawing a standard curve by taking the mass concentration of each ion as a horizontal coordinate and taking the peak area or peak height as a vertical coordinate.

In addition, reference conditions for ion chromatography are: the measurement conditions or parameters are optimized according to the instruction of the instrument, the concentration of the leacheate can be optimized according to the matrix and the composition of the actual sample, and the ion chromatographic analysis conditions given below are used for reference:

(1) reference Condition 1

Anion separation column, carbonate eluent I, flow rate: 1.0ml/min, a suppressor conductivity detector, a continuous self-circulation regeneration suppressor; or carbonate rinse II, flow rate: 0.7ml/min, suppressed conductivity detector, continuous self-circulating regeneration suppressor, CO2 suppressor. Sample introduction amount: 25 μ l.

(2) Reference Condition 2

Anion separation column, hydroxide eluent, flow rate: 1.2ml/min, suppressed conductivity detector, continuous self-circulation regeneration suppressor. Sample introduction amount: 25 μ l.

S5, measuring the sample and the blank sample according to the chromatographic conditions and steps which are the same as those of the standard curve drawing;

the measurement of the sample comprises: according to the same chromatographic conditions and steps as those for drawing a standard curve, a sample is injected into an ion chromatograph to determine the anion concentration, and the retention time is used for qualitative determination, and the instrument response value is used for quantitative determination.

The determination of the blank sample included: the blank sample is injected into an ion chromatograph to determine the anion concentration according to the same chromatographic conditions and procedures as the determination of the sample, and is qualitative by retention time and quantitative by instrument response value.

S6, calculating the mass concentration of inorganic anions Cl-, NO 3-and SO 42-in the sample.

Calculating according to the formula (1):

in the above formula: rho is the mass concentration of anions in the sample, mg/L;

h is the peak area (or peak height) of the anion in the sample;

h0 is the peak area (or peak height) of the anion in the laboratory blank;

a is the intercept of the regression equation;

b is the slope of the regression equation;

f is the dilution factor of the sample;

when the content of the sample is less than 1mg/L, the result is retained to three decimal places; when the content of the sample is more than or equal to 1mg/L, the result retains three significant figures.

In addition, it is necessary to perform: s7 blank test

At least 2 laboratory blank tests should be carried out on each batch (less than or equal to 20) of samples, and the blank test result should be lower than the detection limit of the method; otherwise, the reason should be found out, and the sample cannot be measured until the sample is qualified after reanalysis;

s8 correlation test

The correlation coefficient of the standard curve is more than or equal to 0.995, otherwise, the standard curve is drawn again;

s9, continuous calibration

For each batch (less than or equal to 20) of samples, a standard solution with the concentration of the middle point of the standard curve is analyzed, and the relative error between the measured result and the concentration of the middle point of the standard curve is less than or equal to 10 percent; otherwise, the standard curve is drawn again;

s10, precision control

At least 10% of the replicates per batch (. ltoreq.20) should be tested, and at least one replicate should be tested when the number of samples is less than 10. The relative deviation of the parallel double-sample determination result is less than or equal to 10 percent;

s11 accuracy control

At least 1 standard adding recovery rate measurement should be carried out on each batch (less than or equal to 20) of samples, and the standard adding recovery rate of the actual samples should be controlled between 80% and 120%;

and S12, waste treatment.

In newly issued GB/T50123-2019 geotechnical test method Standard, soil is subjected to salt solubility analysis, and anions still adopt an ultraviolet spectrophotometry method and a chemical titration method, so that the method is low in efficiency and large in error; the method can greatly improve the detection efficiency and quality according to the characteristic of soil salt solubility and the characteristics of instruments and equipment. The method for measuring anions by using the ion chromatography has the advantages of wide linear range, capability of completely meeting the requirement of measuring the anions in common soil and saline-alkali soil, no need of dilution in the measuring process, capability of greatly improving the testing efficiency and reduction of experimental errors.

The ICS 600 ion chromatograph used in the method disclosed by the invention has been used in a laboratory for many years, and the method for drinking water and underground water has been operated for many years, so that the method has obvious advantages in various aspects such as detection, linear range and stability; the ion chromatography is a method for continuously separating, qualitatively and quantitatively determining various coexisting anions or cations by using the ion exchange principle; inorganic anions are the earliest developed and most mature ion chromatography detection method at present, comprise halogen anions such as fluorine, chlorine, bromine and the like, sulfate radicals, thiosulfate radicals, cyanide and the like in a water phase sample, can be widely applied to drinking water quality detection, safety of foods such as beer, beverage and the like, wastewater discharge standard detection, quality control of industrial products such as metallurgical process water samples, petroleum industry samples and the like, and have the advantages of quickness, convenience, high sensitivity and good selectivity which are well known by mass chromatography users.

Cl to be confirmed in the present invention^-、SO₄ ^2-、NO₃ ^-The three anions are the most common anions in water quality analysis, and are measured by ion chromatography in international standards such as HJ 84-2016 (F-, Cl-, NO2-, Br-, NO3-, PO43-, SO32-, SO42-) ion chromatography for determination of inorganic anions in water quality, GB/T5750-2006 (Standard test method for Drinking Water), CJ/T51-2018 (Standard test method for Sewage quality), GB 8538-2016 (Standard test method for Natural mineral Water for Drinking), and the like.

The method comprises the steps of comparing the actual samples by a laboratory method, analyzing and testing the actual samples, and verifying the reliability of experimental data of the method by quality control measures such as method comparison, standard addition, parallel sample addition and the like; the stability of the experimental data of the method is verified by the comparison of the method between laboratories and the comparison of the same sample with the data of other laboratories.

The method is mainly verified by method comparison and comparison among laboratories, wherein the method comparison is performed by comparing a traditional method adopted in GB/T50123 and 2019 geotechnical test method standard newly issued and implemented with a new method adopted in a project, and the feasibility of the new method is determined. The lab-to-lab comparison is a data comparison of the results of the new laboratory method for determining samples with the results of the other new laboratory methods for determining the same batch of samples. The project abandons a single traditional test method of ultraviolet spectrophotometry and chemical titration. Certain manpower and financial resources can be saved for a test center, and the working efficiency of workers is improved; the competitiveness of the experiment test center industry can be improved; enhancing innovation awareness of workers; the method establishes an industry leading position for the smooth development of soil salt-soluble experimental tests in the future.

The present invention and the embodiments thereof have been described above without limitation, and it is within the scope of the present invention that those skilled in the art will be able to devise similar structural modes and embodiments without the inventive concept without departing from the spirit and scope of the present invention.