JP2005331409A - Simplified soil elution test method for heavy metal or the like - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simplified soil elution test method for a heavy metal or the like executed as investigation for a distribution state of a soil contaminated with the heavy metal or the like, or investigation for clarification treatment. <P>SOLUTION: A moisture content of the undried soil is measured after the contaminated soil of an investigation object is sieved to remove a gravel or the like, a fixed amount of the soil is weighed, an organic solvent is added thereto to be mixed and to be shaken for about one minute by a hand, followed to be stood for about 30 minutes, centrifugal separation is carried out thereafter, and the heavy metal or the like is quantitatively determined by a simple analytical method, an ion electrode method, an absorptiometry, an atomic absorption spectroscopy, an ICP emission spectroscopic analytical method, an X-ray fluorescence analytical method or the like, using a filtrate after filtrated with a filter, as a specimen eluate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  This invention has a high correlation with the soil elution simple test method for heavy metals and the like, particularly the so-called official method, which is carried out as an investigation of the distribution state of soil contaminated with heavy metals and the like, or an investigation for purification treatment. It is an obtained method that allows heavy metals to be measured to be eluted from the soil easily and quickly on the site, and enables the measurement of heavy metals etc. on the site using the obtained elution test solution. Belongs to the technical field of simple soil dissolution test method. Incidentally, the heavy metals and the like to be measured by the present invention are cadmium, lead, hexavalent chromium, arsenic, selenium, fluorine, boron, etc., organic phosphorus, total mercury, alkyl mercury, all cyan, PCB, thiuram, simazine, Excluding thiobencarb.

(Regarding Official Law)
In accordance with the enforcement of the Soil Contamination Countermeasures Law, for the quality assessment of soil (contaminated soil, improved treated soil) in related soil contamination investigations and pollution remediation works, dissolution tests based on the so-called official method of Environment Agency Notification No. 46 Simply called the official law).
As shown in Fig. 8, the official dissolution test uses air-dried soil that has been air-dried for about 1 to 7 days to remove the contaminated soil through a 2 mm sieve. Mix the soil with gravel well and use it as the sample soil. The sample soil is weighed, and a pure aqueous solution (prepared so that the hydrogen ion concentration index is 5.8 or more and 6.3 or less by adding hydrochloric acid) is added so that the weight ratio is 10%, Mix and mix the sample solution so that the mixture becomes 500 ml or more on a shaker at normal temperature and normal pressure, adjust the number of shakes to 200 times per minute, and adjust the shake width to 4 cm or more and 5 cm or less. Shake for 6 hours continuously. After shaking, leave for about 10 to 30 minutes, then centrifuge at 3000 rpm for 20 minutes, filter the supernatant under reduced pressure with a membrane filter with a pore size of 0.45 μm, and collect the filtered filtrate. Then, the amount of liquid necessary for quantification is accurately measured and used as a test solution. The above test solution is appropriately diluted or concentrated, and then heavy metals and the like in the test solution are quantified using, for example, an Optima 2000 DV ICP emission spectrophotometer manufactured by Perkinelmer.

However, the liquid preparation operation by the official method requires days (about 1 to 7 days) for air-drying the contaminated soil to be investigated. The air-drying treatment time varies depending on the moisture content of the target soil, and soil with a high moisture content requires a long time. Moreover, even if it sees in the operation | work per day, since a mechanical shake is performed continuously for 6 hours, there will be a big time restriction. In addition, it is necessary to use a shaker, which is a large analyzer, and there are significant restrictions on field work. For this reason, if there are many samples of contaminated soil to be surveyed, it takes a lot of days for analysis and survey by official method, and it is very inconvenient and inconvenient because it prolongs soil contamination survey and soil repair work. This is a major obstacle to implementation.
In other words, in practice, it is required to identify the extent (area and depth) of soil contamination and to evaluate the quality of treated soil after purification treatment at a local site promptly and at low cost with content that is contested. It has been. Therefore, if a simple soil elution test method that is highly correlated with the official method in parallel with a rigorous survey by the official method can be performed quickly and promptly determined, it will be possible to facilitate on-site work and improve work efficiency. In addition, it contributes to shortening the working time. Therefore, there is an urgent need to develop and establish a simple soil dissolution test method.

  Conventionally, in Patent Document 1 below, after adding an extract to sampled soil, mixing the mixture, and then separating the mixture, the solution to be extracted (test solution) can be analyzed simply and quickly. After adding the extract to the sampling soil, a flocculant that does not contain contaminants is further added to the pollutant to be measured, thereby promoting separation of the extract from the mixture of the sampling soil and the extract. A soil analysis method is disclosed. Although this soil analysis method can be carried out easily, quickly and accurately at a low cost, it is basically a method that does not consider the correlation with the official method. The pollutants to be measured by this method are inorganic substances, organic substances, heavy metals and the like. Examples of the extraction liquid include pure water, acidic liquid such as 0.01 to 10 N hydrochloric acid, nitric acid and sulfuric acid, alkaline liquid such as ammonia water, and organic solvents such as alcohols such as methanol and ethanol. The addition amount of the extract varies depending on the properties of the soil, but it is generally said that the addition amount in the range of 1 ml to 100 ml, preferably 2 ml to 50 ml is optimal with respect to 1 g of sampled soil. Examples of the flocculant include inorganic flocculants and organic flocculants. However, any flocculant that does not contain the pollutant and does not adversely affect the pollutant to be measured. It is also described that it may be used. The addition amount of the flocculant varies depending on the flocculant, the properties of the soil, and the extract, but it is described that the concentration of the flocculant is in the range of 1 ppm to 10%, preferably 10 ppm to 5% with respect to the extract. .

  Next, in Patent Document 2 below, an evaluation method capable of grasping and evaluating the contamination status of soil, groundwater, etc. easily and relatively accurately, and shortening the investigation and analysis time and reducing the investigation cost and An evaluation system is disclosed. Of course, this evaluation method and evaluation system can be used to check environmental pollution in the survey target area by accessing it via communication means connected by a terminal device, even if it is an unspecified number of pollutant survey requesters or remote requesters. The degree of contamination (presence / absence and degree of contamination) is certified by data analysis as a third-party organization, and further, it is recognized as a support system for receiving survey cost estimates and survey requests for detailed environmental surveys, and correlation with official methods There is no sex.

Japanese Patent Laid-Open No. 9-72898 JP 2002-168850 A

As described above, the elution test for heavy metals and the like by the official method is pure water extraction with a soil: solvent ratio of 1:10. The dissolution test by the official method can be said to be a method obtained from empirical results, not a method originally considered from the functional aspect of soil. Therefore, it is difficult to perform a theoretical approach, which is a bottleneck in establishing a simple method. However, it is said that the official method of elution with water elutes components such as water-soluble heavy metals and components such as exchangeable heavy metals.
Therefore, in the present invention, components such as heavy metals adsorbed by coordination bonds are not extracted, but a part of components such as exchangeable heavy metals and components such as water-soluble heavy metals can be extracted in a short time. The development was advanced focusing on the use of a solvent that gave a high correlation with the results.

In the official method, since it is air-dried, it takes about 1 to 7 days (the required time varies depending on the water content). Therefore, in the present invention, air drying is not performed. Elution was carried out with solid soil (wet soil as it was), and the air-drying time was dramatically shortened. That is, exchange groups in soil (carboxyl groups contained in humus, silanol groups of clay minerals, etc.) are considered to have no difference in properties due to air drying.
According to the official method, in order to elute heavy metals and the like in the soil, it is specified that a mechanical shaking elution time of 6 hours is required, and a tremendous time is required for the shaking operation. In the present invention, when shaking by shaking for 1 minute, elution is possible by standing for about 30 minutes, and elution operation of heavy metals and the like having high correlation with the official method can be performed in a short time. To save time. In addition, since it is not necessary to use a shaker, which is a large analyzer, the elution operation can be easily performed at low cost on site. In other words, the official method requires a large measurement analyzer, so that it was necessary to carry the soil sample once into the analysis facility and operate it indoors.

Next, as already described, the simple analysis method disclosed in Patent Document 1 is basically a method that does not consider the correlation with the official method, and is originally different from the present invention. The simple analysis method disclosed in Patent Document 1 selects an appropriate extract and flocculant for the soil contaminants to be analyzed, mixes the soil and extract, adds the flocculant, and gently stirs It is a method of mixing by the method of carrying out, etc., and leaving still after that, separating the supernatant liquid of a liquid mixture, and isolate | separating the liquid mixture of a soil and an extract. Adding a flocculant facilitates the separation of the mixture of soil and extract. In short, the simple analysis method disclosed in Patent Document 1 is a method for efficiently extracting and extracting a liquid to be extracted in a short time without requiring a filtration step and a centrifugation step. Therefore, it cannot be positioned as a simple test method that can be used together with the official method, and it does not have any significance to use in combination. This is because, in Paragraph No. [0024] of Patent Document 1, Comparative Example 1 is prepared by a method based on the official method, but the specific content is that 5 g of the sample soil should be 50 g. The water-added mixed solution should be 500 ml or more, and the description should be completely different from the official method, such as mechanical shaking for 6 hours and standing for 30 minutes, shaking vigorously for 2 minutes and standing for 1 hour. Because it is the contents, it does not correspond to the analysis value of the official method.
In short, instead of the conventional operation of “Standing, Centrifugation, and Filtration” as a solid-liquid separation method, the contents are replaced with the operation of adding a flocculant to settle the suspended solids and obtaining the supernatant. It is only a thing.

  Next, the evaluation method and the evaluation system disclosed in Patent Document 2 do not give any consideration to the correlation with the official method. Even if there are many unspecified pollution survey requesters and remote requesters, it is accessed through the communication means connected with the terminal device, and the degree of environmental pollution (presence / absence of contamination) It is only a support system for authenticating by data analysis as a three-party organization, and for receiving a survey cost estimate and a survey request for a detailed environmental survey, and cannot be positioned as a simple test method of the official method.

The object of the present invention is to obtain a result highly correlated with the official method, and can be easily and quickly implemented on site as a simple test method with excellent reliability sufficient to be used together with the official method. It is a method that can be easily obtained, and is to provide an analytical method capable of measuring pollutants such as heavy metals such as lead, arsenic, and fluorine even in the field.
The purpose of the present invention is to promote the progress of local soil contamination investigation and pollution purification work by using in combination with the official method to fill in the inaccuracies and slow operation of the official method with the soil elution simple test method of the present invention. It is to provide a simple soil elution test method for heavy metals and the like that can meet the demands of quick time by complementing the degree.

As a means for solving the problems of the prior art, a soil elution simple test method for heavy metals and the like according to the invention of claim 1,
Measure the moisture content of undried soil that has been debrised and passed through a sieve from the polluted soil (covered soil) to be investigated, weigh a certain amount of the soil, add an organic solvent to this, mix, and mix for about 1 minute After shaking for about 30 minutes, centrifuge and use the filtrate filtered through a filter as the elution test solution, simple analysis method, ion electrode method, absorptiometry, atomic absorption spectrometry, It is characterized in that heavy metals and the like in a liquid are quantitatively measured by ICP emission analysis or fluorescent X-ray analysis.

The invention described in claim 2 is a simple method for testing soil elution of heavy metals and the like described in claim 1,
The debris-contaminated soil is passed through a 2 mm sieve, and the undried soil that has passed through is weighed in an amount equivalent to 50 g of dry soil, added with 500 ml of organic solvent, shaken by shaking for about 1 minute, and allowed to stand for 30 minutes. Centrifugation at about 3000 rpm is carried out for about 10 minutes, the supernatant is filtered under reduced pressure through a membrane filter having a pore size of 0.45 μm, and the obtained filtrate is subjected to simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, It is characterized in that heavy metals and the like in a liquid are quantitatively measured by ICP emission analysis or fluorescent X-ray analysis.

The invention described in claim 3 is the soil elution simple test method for heavy metals and the like described in claim 1 or 2,
As the organic solvent, methanol, ethanol, acetone or the like that can be expected to decrease the viscosity or increase the permeability to the soil particles due to the surface-active effect and does not change the soil pH is added in an amount of 0.1% to 30%. % (Volume concentration) is used.

The invention described in claim 4 is the soil elution simple test method for heavy metals and the like described in claim 1 or 2,
When the measurement target is lead, the filtrate obtained by filtration under reduced pressure with a filter can be selected from simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, ICP emission analysis, or fluorescent X-ray analysis. It is characterized by quantifying lead in the filtrate.

The invention described in claim 5 is the soil elution simple test method for heavy metals and the like described in claim 1 or 2,
When the measurement target is arsenic, the filtrate obtained by filtration under reduced pressure with a filter can be selected from simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, ICP emission analysis, or fluorescent X-ray analysis. It is characterized by quantifying arsenic in the filtrate.

The invention described in claim 6 is the soil elution simple test method for heavy metals and the like described in claim 1 or 2,
When the measurement target is fluorine, the filtrate obtained by filtration under reduced pressure with a filter can be used to quantify fluorine in the filtrate by one of the simple analysis method, ion electrode method, absorptiometry, or fluorescent X-ray analysis method. Features.

In the soil elution simple test method for heavy metals and the like according to the present invention, the air drying that required many days in the official method is omitted, and the contaminated soil uses the solid soil as it is as the unair-dried soil, so the time required for air drying is reduced. It can be eliminated. Instead, in the case of the present invention, the moisture content of the contaminated soil is measured, and based on the measurement result, the weight is adjusted to 50 g in terms of dry soil, and the solvent is added to this and mixed. ing.
In the official method, elution of heavy metals and the like is performed by extraction with pure water of soil: solvent = 1: 10, but in the case of the present invention, organic solvents, that is, components such as heavy metals adsorbed by coordination bonds are extracted. Without being able to extract a part of components such as exchangeable heavy metals and components such as water-soluble heavy metals in a short period of time, a solvent having a high correlation with the official method, Specifically, it can be expected to increase the permeability of the solvent to the soil particles due to the decrease in viscosity or surface-active effect, and the elution effect using organic solvents such as methanol, ethanol, acetone, etc. that do not change the soil pH To increase.
Therefore, in the official method, where continuous shaking for 6 hours is specified, the elution test result of heavy metals and the like having a high correlation with the official method is obtained by shaking operation by extremely short hand shaking for about 1 minute. be able to. This is a shaking operation by hand and does not require a shaker, which is a large analyzer, making it possible to perform simple and quick low-cost elution operations locally.

Using the filtered sample solution obtained by the above elution operation as an elution test solution, it is sufficient to select an optimal analysis method for the target component of measurement and quantitatively measure heavy metals, etc. Quantitative measurement of heavy metals in liquids by ion electrode method, absorptiometry, atomic absorption spectrometry, ICP emission analysis, or fluorescent X-ray analysis, etc. A rapid survey that adapts to progress can be realized.
Incidentally, when the official method is used, it takes about 2 to 8 days for the whole process. However, according to the method of the present invention, the time required for the whole process is only 2 hours and 30 minutes. It has a special effect on shortening the required time.

  As shown in the process chart in Fig. 1, we measured the moisture content of the undried soil that was passed through a 2mm sieve after debris from the polluted soil (solid soil) to be investigated, and based on the moisture content. Weigh the soil equivalent to 50 g of dry soil and place it in a polyethylene container. To this, 500 ml of an organic solvent is added and mixed, and shaken by shaking for about 1 minute. After standing for about 30 minutes, centrifugation at about 3000 rpm is performed for about 10 minutes. The supernatant liquid is filtered under reduced pressure with a membrane filter having a pore size of 0.45 μm, and the obtained filtrate is used as an elution test solution. The simple analysis method, ion electrode method, absorptiometry, atomic absorption analysis, which are widely known as on-site measurement methods. Quantitative measurement of heavy metals and the like in the liquid by the method, ICP emission analysis method or fluorescent X-ray analysis method.

  As already known, the simple analysis method is a method using various measurement kits such as test papers and ampoules. The ion electrode method uses a JIS standard ion electrode and measures the ion concentration by a potential difference. Absorptiometry is a JIS standard method called colorimetric analysis, which is known as a method for quantifying and qualifying target components by adding a reagent to a solution to cause color development, and measuring the absorbance by applying light to the solution. It is. The atomic absorption analysis method is roughly divided into a flame method and a flameless method according to a method of atomizing elements, and is an analysis method using light absorption by atoms (JIS K 0121). The ICP emission analysis method is a method in which atoms are emitted when a sample is introduced into an argon plasma. Therefore, the atomic and ion spectrum lines unique to the element are dispersed with a spectroscope, and the emission intensity is measured for each wavelength (JIS). K 0116). X-ray fluorescence analysis is known as the most suitable method for rapid analysis because it can simultaneously analyze multiple elements. However, the analysis method is not limited to the above examples. As other simple analytical methods to be performed on site, simple water quality inspection instruments such as pack test (Kyoritsu) or "Kyoritsu" rapid water quality testing reagent-method using spectrophotometer, Yoshitest (Yoshitomi Fine Chemical), etc. You can also.

  As an organic solvent that facilitates elution, methanol, ethanol, acetone, etc., which can be expected to decrease viscosity or increase permeability to soil particles due to surface-active effects and do not change soil PH, are added as 0 It is preferable to use in the range of 1% to 30% (volume concentration).

  Lead contaminated soil containing lead A and one non-contaminated soil (volcanic ash soil topsoil and volcanic ash soil subsoil alone or in combination), Wako Pure Chemical Industries, Ltd. In addition, using the simulated lead-contaminated soil prepared, the amounts of lead eluted by the method according to the present invention and the method by the official method were compared.

(Example of the present invention)
Nine air-dried sample soils whose moisture content was measured in advance were weighed using an electronic balance so as to be 50 g in terms of dry soil based on the moisture content. On the other hand, 5 ml of special grade reagent methanol manufactured by Wako Pure Chemical Industries, Ltd. was added to 995 ml of pure water to prepare an extraction solvent, and the 50 g sample soil and 500 ml of extraction solvent were put into a 1 L polyethylene container and mixed. . The polyethylene container was shaken by hand for 1 minute and allowed to stand for 30 minutes. Then, after centrifuging at 3000 rpm for 15 minutes, the supernatant was subjected to vacuum filtration using an ADVANTEC membrane filter having a pore diameter of 0.45 μm. After the obtained filtrate was diluted so as to be suitable for quantification, the lead in the test solution was quantitatively measured using an Optima 2000 DV ICP emission spectrophotometer manufactured by Perkinelmer.

(Comparative example = official method)
For each of the nine sample soils that had been air-dried, 50 g was weighed using an electronic balance and mixed with 500 ml of pure water in a 1 L polyethylene container. The polyethylene container was shaken continuously for 6 hours with a reciprocating shaker. After leaving still for 30 minutes, centrifugation at 3000 rpm was performed for 15 minutes. Thereafter, the supernatant was filtered under reduced pressure using a membrane filter manufactured by ADVANTEC having a pore diameter of 0.45 μm. After the obtained filtrate was diluted so as to be suitable for quantification, the lead in the test solution was quantitatively measured using an Optima 2000 DV ICP emission spectrophotometer manufactured by Perkinelmer.

(Contrast and examination)
There is a high correlation between the amount of lead eluted in the above comparative example by the official method and the amount of lead eluted by the method of the above embodiment of the present invention, as shown in FIG. 2 and FIG. Was confirmed. That is, the correlation coefficient (R) was a high value of 0.976 (indicated by the contribution rate R ² in FIG. 3). The regression line y in FIG. 3 was calculated using the least square method, and was calculated by the following equation.
[Equation 1]
y = (Σxi · yi−1 / nΣxi · Σyi) / (Σxi−1 / n (Σxi) ² ) x

Moreover, the contribution rate R ² were determined by the following equation. R is a correlation coefficient.
[Equation 2]
R ² = (Σxi · yi−Σxi · Σyi / n) ² / (Σxi ² − (Σxi) ² ) / n)
(Σyi ² − (Σyi) ² / n)
The calculated value of R is 0.8 or more, and it is determined that there is a strong correlation. Further, in the determination of significance using the F test, F = 159.26 is calculated and is larger than the rejection value F (1.φ) = 12.55. Therefore, the present invention is statistically detected at a significance level of 1%. It was proved that the elution value of lead in the official method can be estimated in a very short time with the simple method of.
That is, by measuring the amount of lead eluted by the method of the present invention, it is possible to estimate the result of the amount of lead eluted by an official dissolution method in a short time.

  One arsenic-contaminated B factory soil, one C-contaminated soil, one D-contaminated soil, two E-contaminated soils, and uncontaminated soil (volcanic ash soil topsoil and volcanic ash soil Using the simulated arsenic contaminated soil prepared by adding disodium hydrogen arsenate, a special grade reagent manufactured by Wako Pure Chemical Industries, Ltd. to 8 points, the method according to the present invention and the method according to the official method The amount of lead eluted was compared.

(Example of the present invention)
Nine air-dried sample soils whose moisture content was measured in advance were weighed using an electronic balance so that the soil content was 50 g in terms of dry soil based on the moisture content. On the other hand, 5 ml of a special grade reagent methanol manufactured by Wako Pure Chemical Industries, Ltd. was added to 995 ml of pure water to prepare an extraction solvent, and the 50 g sample soil and 500 ml of extraction solvent were put into a 1 L polyethylene container. Mixed. The polyethylene container was shaken by hand for 1 minute and allowed to stand for 30 minutes. Then, after centrifuging at 3000 rpm for 15 minutes, the supernatant was filtered under reduced pressure using a membrane filter manufactured by ADVANTEC having a pore diameter of 0.45 μm. After the obtained filtrate was diluted so as to be suitable for quantification, arsenic in the test solution was quantitatively measured using an Optima 2000 DV ICP emission spectrophotometer and a hydride generator manufactured by Perkinelmer.

(Comparative example = official method)
For each of the nine sample soils that had been air-dried, 50 g was weighed using an electronic balance and mixed with 500 ml of pure water in a 1 L polyethylene container. The polyethylene container was shaken continuously for 6 hours with a reciprocating shaker. After leaving still for 30 minutes, centrifugation at 3000 rpm was performed for 15 minutes. Thereafter, the supernatant was filtered under reduced pressure using a membrane filter manufactured by ADVANTEC having a pore diameter of 0.45 μm. The obtained filtrate was diluted so as to be suitable for quantification, and arsenic in the test solution was quantitatively measured using an Optima 2000 DV ICP emission spectrophotometer and a hydride generator manufactured by Perkinelmer.

(Contrast and examination)
There is a high correlation between the amount of arsenic eluted in the above comparative example by the official method and the amount of arsenic eluted by the method of the above embodiment of the present invention, as shown in the comparison results in FIGS. Was confirmed. That is, the correlation coefficient (R) was a high value of 0.998 (indicated by the contribution rate R ² in FIG. 5). The regression line y in FIG. 5 was calculated using the least square method, and was calculated by the following equation.
[Equation 3]
y = (Σxi · yi−1 / nΣxi · Σyi) / (Σxi−1 / n (Σxi) ² ) x

Moreover, the contribution rate R ² were determined by the following equation. R is a correlation coefficient.
[Equation 4]
R ² = (Σxi · yi−Σxi · Σyi / n) ² / (Σxi ² − (Σxi) ² / n)
(Σyi ² − (Σyi) ² / n)
The calculated value of R is 0.8 or more, and it is determined that there is a strong correlation. Further, in the determination of significance using the F test, F = 3339.65 is calculated, and since the rejection value F (1.φ) = 9.65 is greater, the significance level of the present invention is 1%. It was proved that the elution value of lead in the official method can be estimated in a very short time by the simple method by.
Based on the above results, by measuring the amount of arsenic eluted by the method of the present invention, the elution value of arsenic by the official method can be estimated in a very short time.

  The amount of fluorine eluted from the method according to the present invention and the method according to the official method were compared using 4 soils from the F factory and 2 soils from the G factory, which are contaminated soils containing fluorine.

(Example of the present invention)
The five sample soils, which had been measured in advance for moisture content, were weighed using an electronic balance so that the sample soil was 50 g in terms of dry soil. On the other hand, 5 ml of special grade reagent methanol manufactured by Wako Pure Chemical Industries, Ltd. was added to 995 ml of pure water to prepare an extraction solvent, and the 50 g sample soil and 500 ml of extraction solvent were put into a 1 L polyethylene container and mixed. . The polyethylene container was shaken by hand for 1 minute and allowed to stand for 30 minutes. Thereafter, centrifugation at 3000 rpm was performed for 15 minutes. Thereafter, the supernatant was filtered under reduced pressure using a membrane filter manufactured by ADVANTEC having a pore diameter of 0.45 μm. The obtained filtrate was concentrated and distilled so as to be suitable for quantification, and then the fluorine in the filtrate was quantified by absorptiometry using a UV-1600 spectrophotometer manufactured by Shimadzu Corporation.

(Comparative example = official method)
For each of the five sample soils that had been air-dried, 50 g was weighed using an electronic balance, and mixed with 500 ml of pure water in a 1 L polyethylene container for adjustment. The polyethylene container was shaken continuously for 6 hours with a reciprocating shaker. After leaving still for 30 minutes, centrifugation at 3000 rpm was performed for 15 minutes. Thereafter, the supernatant was filtered under reduced pressure using a membrane filter manufactured by ADVANTEC having a pore diameter of 0.45 μm. The obtained filtrate was concentrated and distilled so as to be suitable for quantification, and then the fluorine in the filtrate was quantified by absorptiometry using a UV-1600 spectrophotometer manufactured by Shimadzu Corporation.

(Contrast and examination)
There is a high correlation between the amount of fluorine eluted in the above comparative example by the official method and the amount of fluorine eluted by the method of the above embodiment of the present invention, as shown in the comparison results in FIGS. Was confirmed. That is, the correlation coefficient (R) is 0.999 (indicated by the contribution rate R ² in FIG. 7), which is a high value. The regression line y in FIG. 7 was calculated using the least square method and was obtained by the following equation.
[Equation 5]
y = (Σ (xi · yi−1 / nΣxi · Σyi) / (Σxi−1 / n (Σxi) ² ) x

Moreover, the contribution rate R ² were determined by the following equation. R is a correlation coefficient.
[Equation 6]
R ² = (Σxi · yi−Σxi · Σyi / n) ² / (Σxi ² − (Σxi) ² / n)
(Σyi ² − (Σyi) ² / n)
The calculated value of R is 0.8 or more, and it is determined that there is a strong correlation. Further, in the determination of significance using the F test, F = 256.46 is calculated and is larger than the rejection value F (1.φ) = 34.12. It was proved that the elution value of fluorine by the official method can be estimated in a very short time by the simple method.
Based on the above results, it is possible to estimate the elution value of fluorine by the official method in a very short time by measuring the amount of fluorine eluted by the method of the present invention.

It is process drawing of the soil elution simple test method of heavy metals etc. which concern on this invention. It is a comparison table | surface of the lead elution value of the 1st Example of this invention and the comparative example by an official method. It is a correlation diagram of the lead elution value by the method of this invention and an official method. It is a comparison table of the arsenic elution value of 2nd Example of this invention and the comparative example by an official method. It is a correlation diagram of the arsenic elution value by the method of this invention and an official method. It is a comparison table | surface of the fluorine elution value of 3rd Example of this invention, and the comparative example by an official method. It is a correlation diagram of the fluorine elution value by the method of the present invention and the official method. It is a process figure of elution operation by an official method.

Claims (6)

  Measure the moisture content of undried soil that has been debrised and passed through a sieve from the polluted soil (covered soil) to be investigated, weigh a certain amount of the soil, add an organic solvent to this, mix, and mix for about 1 minute After shaking for about 30 minutes, centrifuge and use the filtrate filtered through a filter as the elution test solution, simple analysis method, ion electrode method, absorptiometry, atomic absorption spectrometry, A simple test method for soil elution of heavy metals and the like, characterized by quantitatively measuring heavy metals and the like in a solution by ICP emission analysis or fluorescent X-ray analysis.   The debris-contaminated soil is passed through a 2 mm sieve, and the undried soil that has passed through is weighed in an amount equivalent to 50 g of dry soil, added with 500 ml of organic solvent, shaken by shaking for about 1 minute, and allowed to stand for 30 minutes. Centrifugation at about 3000 rpm is carried out for about 10 minutes, the supernatant is filtered under reduced pressure through a membrane filter having a pore size of 0.45 μm, and the obtained filtrate is subjected to simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, The simple method for testing soil elution of heavy metals and the like according to claim 1, characterized in that heavy metals and the like in the liquid are quantitatively measured by ICP emission analysis or fluorescent X-ray analysis.   As the organic solvent, methanol, ethanol, acetone or the like that can be expected to decrease the viscosity or increase the permeability to the soil particles due to the surface-active effect and does not change the soil pH, is added in an amount of 0.1% to 30%. % Simple method for soil elution testing of heavy metals and the like according to claim 1, wherein the method is used in a range of% (volume concentration).   When the measurement target is lead, the filtrate obtained by filtration under reduced pressure with a filter can be selected from simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, ICP emission analysis, or fluorescent X-ray analysis. The simple method for soil elution testing of heavy metals and the like according to claim 1 or 2, wherein lead in the filtrate is quantified.   When the measurement target is arsenic, the filtrate obtained by filtration under reduced pressure with a filter can be selected from simple analysis, ion electrode method, absorptiometry, atomic absorption analysis, ICP emission analysis, or fluorescent X-ray analysis. The simple method for soil elution testing of heavy metals and the like according to claim 1 or 2, wherein arsenic in the filtrate is quantified. When the measurement target is fluorine, the filtrate obtained by filtration under reduced pressure with a filter can be used to quantify fluorine in the filtrate by one of the simple analysis method, ion electrode method, absorptiometry, or fluorescent X-ray analysis method. A simple soil elution test method for heavy metals or the like according to claim 1 or 2, characterized by the following.

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