JPH02134563A - Method and apparatus for analyzing insoluble fine particle in water - Google Patents

Abstract

PURPOSE:To make it possible to determine the amounts of various metal ions even if the amounts are very minute by completely dissolving clad by addition of organic acid and heat treatment, and enriching the dissolved component with ion exchange resin. CONSTITUTION:A dissolving agent (complex forming agent) 2 incorporating organic acid is added into specimen water 1 incorporating metal clad. The water is heated, and the metal clad is dissolved 11. Then, a complex decomposing agent 3 such as oxidizing agent or reducing agent is added, and the complex is decomposed 12. Metal ions are enriched 13 by using cation exchange resin 4. Then an eluate 5 is added into the resin, and the metal ions are eluted 14. The ions are further separated into metal ions for every kind of metal 15 by using a cation exchange resin 6. A coloring agent 7 is added into the solution incorporating the separated metal ions. The absorbance after coloring 16 is detected 17. In this way, the amount of the respective metal ions which are separated for every metal is detected. As the dissolving agent 2 described above, it is desirable to use dicarboxylic acid and oxycarboxylic acid forming 5- and 6-membered-ring complexes together with the metal.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method and apparatus for analyzing insoluble particulates in water, and in particular to an automatic monitoring system for water used in nuclear power plants, thermal power plants, etc. The present invention relates to a method and apparatus for analyzing insoluble particulates in water, which are suitable for use in water.

[Conventional technology] Generally, water supply for nuclear power plants, thermal power plants, etc.

In the condensate, metal components contain ionic and insoluble fine particles (
It exists in trace amounts as a cladding (cladding), and it is necessary to continuously monitor the amount of this metal component in plants.

As a conventional technique for analyzing and monitoring this kind of metal, for example, Japanese Patent Application Laid-Open No. 127152/1983 is disclosed.

A technique described in Japanese Patent Application Laid-Open No. 58-218649 is known. This conventional technology focuses on the iron contained in the sample water to be analyzed, and by adding a thioglycolic acid solution to the sample water and heating it, or adding hydrochloric acid and heating it, the clad iron is dissolved and converted into ionic form. The total amount of iron (total iron) including iron that originally existed in ionic form is analyzed.

In addition, as other conventional techniques, for example, Japanese Patent Laid-Open No. 61-90
A technique described in Publication No. 059 and the like is known. In this conventional technique, insoluble iron is dissolved and analyzed without heating by simply adding an ionizing agent, such as oxalic acid, to water containing a large amount of iron.

In all of the above conventional techniques, after dissolving insoluble iron, a reducing agent is added to equalize the valence of iron ions, and then the p of the solution is
The amount of total iron is determined by adjusting H and reacting with a coloring agent and measuring the absorbance.

[Problems to be Solved by the Invention] In the prior art, the metal to be analyzed is only iron, and other metals such as Co and Ni are analyzed.

It is not possible to analyze Cu, Zn, etc., and it does not involve a concentration operation, so when analyzing high-purity water used in nuclear power plants, etc., it is difficult to determine the amount of metals contained. There is a problem in that the amount is so low that it falls below the lower detection limit and becomes impossible to analyze.

Furthermore, taking iron as an example as a compound state of insoluble fine particles (cladding), α-Fe, 03.03.
y-Fe20. t Fe, O□, a-Fe○OH, γ-
As Fe○OH1 amorphous trade form, a-Fe, 03. Fe
(OH), but with the addition of hydrochloric acid.

There are compound states that cannot be dissolved by heating or addition of an organic acid, and in such cases, the conventional technology
There was a problem in that it was impossible to perform accurate analysis.

The purpose of the present invention is to solve the problems of the prior art described above,
An object of the present invention is to provide a method and apparatus for analyzing insoluble particulates in water, which completely dissolves the cladding and makes it possible to quantify various metal ions even in extremely small amounts.

[Means for Solving the Problems] According to the present invention, the above object is achieved by completely dissolving the cladding by adding an organic acid and heat treatment, and by concentrating the dissolved components with an ion exchange resin, extremely trace amounts of the cladding are dissolved. This is achieved by making it possible to analyze metals such as iron, and quantifying metal ions including iron using a separation column using an ion exchange resin.

According to the means according to the present invention described above, the dissolved state of the metal ions after dissolving the cladding may not be in the optimum state for concentration in the concentration column. In this case, in the present invention, by adding an oxidizing agent or a reducing agent to the solution after heating and dissolving it with an organic acid and heating it, it is possible to convert the metal ion into a dissolved state that can be concentrated.

[Effect] A dicarboxylic acid that reacts with metals to form 5- and 6-membered rings.

Organic acids such as oxycarboxylic acids have a large stability constant of the complex and effectively act on dissolving the cladding.

In order to apply it to an automatic analysis method of metal ions, it is necessary to complete the dissolution of the cladding in a short time, and for this purpose, the present invention provides a method in which the organic acid is added to sample water containing the cladding and then heated. This promotes the complex formation reaction.

The organic acid used to dissolve the cladding dissociates in water to form anions (Ln-). On the other hand, organic acid complexes of metal ions also exist very stably as anions. For this reason, if you try to concentrate the solution after dissolving the crud using a concentration column packed with anion exchange resin, the organic acid ions added in excess during crud dissolution will be concentrated, resulting in the concentration rate of the metal complex. cannot be improved.

In order to concentrate only metal ions, it is necessary to use a concentration column filled with a cation exchange resin that does not concentrate organic acid ions. In the present invention, the metal complex can be decomposed into an organic acid and a metal cation by adding an oxidizing agent or a reducing agent as a complex decomposing agent to the aqueous solution after dissolving the cladding and performing heat treatment. Using a concentration column filled with ion exchange resin, only metal ions can be concentrated without concentrating free organic acids and r-ions.

[Example] Hereinafter, an example of the method and apparatus for analyzing insoluble particulates in water according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram explaining the analysis procedure of the first example of the present invention, FIG. 2(a) is a diagram showing a fine particle dissolution curve of a solution containing Fe, Figure 2 (b)
3 is a diagram illustrating the treatment effect of a complex decomposer, FIG. 3 is a diagram illustrating an example of an analytical chromatogram of metal ions, and FIG. 4 is a block diagram illustrating the configuration of an analysis device according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a metal ion analysis chromatogram according to the first embodiment of the present invention. In Fig. 4, 1 is sample water, 2 is a solubilizer, 3 is a complex decomposer, 5 is an eluent, 7 is a coloring agent, 9, 10, 12, 14, 19゜22 is a pump,
11.13 is a heater, 15.20 is a switching valve, 16.
18 is a concentration column, 17 is a mass flow meter, 21 is a separation column, and 23 is a photometer with a flow cell.

First, the analysis procedure will be explained with reference to FIG.

(1) A dissolving agent 2 containing an organic acid that forms a complex with metal is added to sample water 1 containing metal cladding and heated to form a metal complex and dissolving the metal cladding [Procedure (a)] .

(2) Next, a complex decomposer 3 such as an oxidizing agent or a reducing agent is added to decompose the complex, and at the same time, the ion valence of the metal ions is made uniform, and then a cation exchange resin 4 is used to decompose the metal ions. Concentrate [hand 1'1ff (b).

(c)].

(3) Add the eluent 5 to the cation exchange resin 4 concentrating metal ions to elute the metal ions.

Furthermore, this eluent containing metal ions is separated into metal ions for each metal using a cation exchange resin 6.
Steps (d), (e)].

(4) Detect the amount of each metal ion separated for each metal by adding coloring agent 7 to the solution containing the separated metal ions and detecting the absorbance after color development [Step (f)
, (g)].

The clad dissolving agent 2 used in the above-mentioned analysis procedure (a) is
It is preferable to use dicarboxylic acids and oxycarboxylic acids that form 5- or 6-membered ring complexes with metals.

FIG. 2(a) shows a particle dissolution curve when sample water containing Fe, 04 particles was treated using an oxalic acid solution as a clad dissolving agent. ■The curve shown as 0.05
The case of normal temperature treatment (25° C.) with IloΩ/Q oxalic acid solution is shown, and it is shown that the cladding is hardly dissolved in this case. In addition, the curve indicated by [stock] is 0.0
The case of heat treatment at 70° C. using a 5mo Q /Ω oxalic acid solution is shown, and it can be seen that in this case, the cladding can be completely dissolved in about 10 minutes.

FIG. 2(b) illustrates the treatment effect of using a complex decomposer.

When sample water containing iron ions is treated with oxalic acid at room temperature,
As explained with reference to FIG. 2(a), since iron ions do not form a complex with oxalic acid, iron cations are present in the sample water. Therefore, iron ions are concentrated in the subsequent concentration treatment using a cation exchange resin, and after concentration elution, almost 100% of the iron ions contained in the sample water can be recovered. However, in this case, the iron in the form of cladding is not ionized, so it is not concentrated, and the iron in the form of cladding in the sample water cannot be detected.

Furthermore, when sample water containing iron ions is heat-treated with oxalic acid, the clad iron becomes a complex and the iron ions also form a complex at the same time, as explained in Figure 2 (a). Becomes an anion. Therefore, even if a subsequent concentration treatment using a cation exchange resin is performed in this state, iron ions cannot be concentrated, and iron ions cannot be recovered even by concentration 18.

Therefore, in the present invention, sample water containing iron ions is heat-treated with oxalic acid and then heat-treated with a complex decomposer such as nitric acid. As a result, all the iron ions and cladding contained in the sample water once form a complex, and then are decomposed to become iron ions and contained in the solution. Therefore,
This iron ion is concentrated in the subsequent concentration treatment using a cation exchange resin, and after concentration elution, approximately 97% of the total iron in the sample water is concentrated.
% can be recovered.

The aforementioned complex decomposers include nitric acid, potassium chlorate,
In addition to oxidizing agents, such as potassium persulfate, it is also possible to use reducing agents. However, as shown in the example of the metal ion analytical chromatogram shown in Figure 3, iron ions are
``Fe'' is about 20 times more sensitive than ``Fe'', and when metal ions are separated and quantified, Fe''+ cannot be separated from Mn''+, so iron ions are converted to Fe3+ and the ions are It is desirable to equalize the valence, and it is desirable to use an oxidizing agent as the complex decomposer. By using an oxidizing agent as the complex decomposer, Fe It is possible to make the ionite aperture uniform.

FIG. 4 shows the configuration of an analyzer for actually carrying out the analysis procedure shown in FIG. 1 described above.

In FIG. 4, a sample water 1 containing cladding is sent to the analysis channel by a sample water pump 9, and a solubilizing agent 2 is added to the sample water 1 via a dissolving agent feeding pump 10. be done. The sample water 1 containing the dissolving agent 2 is sent to the heater 11, where the metal cladding and metal ions contained in the sample water 1 are formed into a complex and dissolved. After that, the complex decomposer 3 is added to the sample water 1 that has exited the heater 11 using the liquid feeding pump 1.
Add through 2. When this solution is sent to the heater 13, the dissolved complexes are decomposed into metal ions, and at the same time, the ion valences of the metal ions are made uniform.

The solution treated in this way is further transferred to the liquid feeding pump 1.
4. Concentration column 16 or 18 via switching valve 15
sent to. The concentration columns 16.18 are equipped with a cation exchange resin that concentrates metal ions, and one side is alternately connected to the pump 14 side and the mass flow meter 17 side by switching control of the switching valve 15.20. and the other side is connected to the liquid feeding pump 19 side of the eluent 5 and the separation force ram 21 side. The illustrated state is the concentration column 1.
6 shows a state in which a solution containing ionized metal ions is injected through the switching valve 15, and the metal ions in the solution injected into the concentration column 16 are transferred to the cation exchanger in the concentration column 16. Absorbed and concentrated by resin. As a result, the solution from which metal ions have been removed is transferred to the switching valve 20. It is discharged via the mass flow meter 17.

On the other hand, in the state before the switching valve 15.20, the concentration column 18, which is concentrating metal ions, is connected to the liquid feed pump 1.
9. The eluent 5 is injected through the switching valve 15, and the metal ions concentrated in the cation exchange resin in the concentration column 18 are eluted into the eluent 5, and the eluent containing this metal ion is passed through the switching valve 2o. is sent to the separation column 21 via.

The separation column 21 is composed of a cation exchange resin,
The metal ions contained in the eluent 5 are separated by metal type, and the eluent containing different types of metal ions is discharged along the time axis.

The coloring agent 7 is added to the solution from the separation column 21 containing the metal ions separated in this manner via the liquid feed pump 22. The coloring agent 7 is preferably a reagent capable of reacting with all of the separated metal ions to develop a color, and pyridylazoresorcin and its derivatives are preferable. The color developing agent 7 develops a color in accordance with the amount of metal ions contained in the solution, and its absorbance is measured by a photometer 23 with a flow cell, thereby quantifying the metal ions.

FIG. 5 shows the side of the chromatogram measured according to the first embodiment of the present invention described above. According to this embodiment, all the metals contained in the sample water 1 are reliably separated and quantified. can do.

In addition, in the configuration shown in FIG. 4, the concentration column 16.1
The switching period by the switching valve 15.20 of 8 is set as appropriate depending on the separation time of metal ions by the separation column 21 or the concentration of metal ions in the solution injected into the concentration column 16.18.

FIG. 6 is a diagram explaining the analysis procedure of the second example of the present invention, and FIG. 7 is a diagram showing a dissolution curve of the cladding with hydrochloric acid.

In the second embodiment of the present invention, the cladding is dissolved using an inorganic acid dissolving agent, and is carried out by the following procedure.

(1) A dissolving agent 24 made of an inorganic acid is added to the sample water 1 containing the cladding, and the cladding is dissolved by adding an additive treatment [procedure (a)].

(2) By adding a decomposing agent such as an oxidizing agent or a reducing agent 25 and performing a heat treatment, the ion valence is made uniform [
Step (b)].

(3) Next, this solution is electrodialyzed to remove anions, adjust the pH, and then concentrate the metal ions [Procedure (
0),,(d)].

The subsequent procedure is the same as in the case of the first embodiment of the present invention described above.

As an example of the inorganic acid used as the dissolving agent in the above procedure (a), the dissolution curve of the cladding is shown in FIG. 7 when hydrochloric acid is used.

As can be understood from the solubility curve shown in Figure 7, hydrochloric acid I
In the case of heat treatment at 90° C. with an N solution, as shown in curve 27, Fe, O, and fine particles cannot be completely dissolved. However, when heat-treated at 90° C. with a 2N hydrochloric acid solution, Fs, O, and fine particles can be completely dissolved in about 30 minutes, as shown in curve 28. Even in the case of dissolution with such an inorganic acid, the ionic valence of the metal ions is made uniform as in the case of the first embodiment. Further, it is impossible to concentrate metal ions from such a solution containing 2N hydrochloric acid and an oxidizing agent using a cation exchange resin. Therefore, in the second embodiment of the present invention, after removing anions and adjusting the pH to 2 to 4 by electrodialysis using an anion exchange membrane or an anion exchange tube,
We are trying to concentrate metal ions.

The second embodiment of the present invention as described above can also provide the same effects as the first embodiment of the present invention.

In the first and second embodiments of the present invention described above, it is necessary to add a clad dissolving agent, a complex decomposing agent, etc. to the sample water, but there is a possibility that trace amounts of metal impurities may be mixed into these additives. If this happens, accurate analysis of the sample water cannot be performed.

Therefore, it is necessary to remove impurities from these additives before adding them to sample water.

FIGS. 8 to 10 are diagrams illustrating a method for removing trace impurities contained in the clad dissolving agent and the complex decomposing agent. In Figures 8 to 10, 29 is a cooling tank;
o is a pump, 31 is a heating container, 32 is a heater, 33 is a porous tube, 34 is a cation exchange membrane, 35 is an acid solution,
38 is a cation exchange tube, 39 is a Teflon tube, and other symbols are the same as in FIG. 4.

In the example shown in FIG.
It is sent to a heating container 31 which is heated by a heater 32.

Salt or nitric acid sent into the heating container 31 is heated by the heater 32 and vaporized. The sample water 1 containing the cladding passes through the porous tube 33 within the heating container 31 .

The porous tube 33 allows gas to pass therethrough, and hydrochloric acid or nitric acid is added to the sample water 1 through this porous tube. Metal impurities in hydrochloric acid or nitric acid do not vaporize, so sample water 1
Hydrochloric acid or nitric acid, which does not contain any impurities, can be added.

The example shown in FIG. 9 is an example in which impurities are removed by electrodialysis using a cation exchange membrane. In this example, an acid solution 35 is sent to one side of two tanks separated by a cation exchange membrane 34, an anode 36 is provided in this cypress, and pure water is sent to the other tank. A cathode 37 is provided in this tank. Metal ion impurities in the acid solution sent into the tank in which the anode 36 is provided pass through the cation exchange membrane 34 and move to the pure water side when passing through this tank, and the impurities are removed. In this example, the quasi-solution from which impurities have been removed in this way can be added to the sample water 1 via the liquid feed pump 10 or 12.

The example shown in FIG. 10 is an example in which impurities in an acid solution are removed using a cation exchange tube. In this example, the inner tube has a cation exchange tube 38, and the outer tube has a Teflon tube 3.
The culture solution 35 is sent into the cation exchange tube 38 of the inner tube of the double tube using 9, the cathode 40 and the anode 41 are provided inside the outer tube 39, a potential is applied, and pure water is sent into the outer tube. It is something.

In this example, the inside of the cation exchange tube 38 is filled with acid solution 3.
5, metal ion impurities in the acid solution pass through the cation exchange tube 38 and move to the pure water side, and the impurities in the acid solution 35 are removed.

The acid solution is added to the sample water 1 via pump 10 or 12.

The method of removing impurities in an acid solution by electrodialysis shown in FIGS. 9 and 10 above is applicable even if the acid solution is an inorganic acid.
An organic acid may be used, but when the acid solution is an organic acid, it is more effective to ionize metal impurities by adding an oxidizing agent to the organic acid solution in advance and heat treating it. It is.

In the first and second embodiments of the present invention described above, it is possible to use the clad dissolving agent, complex decomposing agent, etc. added to the sample water after completely removing impurities using the impurity removal method described above. The metals in the sample water can be separated and accurately quantified for each metal.

Further, the procedure for performing electrodialysis in the second embodiment of the present invention described above can be performed in the same manner as in the method for removing impurities by the dialysis method described above. That is, Figures 9 and 10
In the figure, instead of the acid solution 35, a treatment solution that has completed the ion valence equalization procedure is supplied to the cation exchange membrane 35.
In place of the cation exchange tube 38, an anion exchange membrane and an anion exchange tube may be used, and the electric field may be reversed in FIG.

In this way, the anions in the processing solution are
In any case shown in Figure 10, it will be moved into pure water, and the PH of the processing solution will change! ! It is possible to make one adjustment.

[Effects of the Invention] As explained above, according to the present invention, it is possible to completely dissolve and analyze insoluble fine particles (crud) present in trace amounts in water, and it is possible to quantify extremely trace amounts of metal components. Moreover, since the reaction is carried out in a thin tube, accurate automatic continuous analysis of each metal can be performed without external contamination.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the analysis procedure of the first embodiment of the present invention, FIG. 2(a) is a diagram showing a fine particle dissolution curve of a solution containing Fe, O, and fine particles using an oxalic acid solution, Figure 2 (b)
3 is a diagram illustrating the treatment effect of a complex decomposer, FIG. 3 is a diagram illustrating an example of an analytical chromatogram of metal ions, and FIG. 4 is a block diagram illustrating the configuration of an analysis device according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a metal ion analysis chromatogram according to the first embodiment of the present invention, FIG. 6 is a diagram explaining the analysis procedure of the second embodiment of the present invention, and FIG. 7 is a diagram showing the analysis of cladding using hydrochloric acid. Figures 8 and 9 showing dissolution curves. FIG. 10 is a diagram illustrating a method for removing trace impurities contained in the clad dissolving agent and the complex decomposing agent. 1...Sample water, 2...Solubilizing agent, 3...
...Complex decomposer, 5...Eluent, 7...
... Color former, 9, 10, 12° 14.19, 22.3
0...Pump, 11,13...Heater, 15.20...Switching valve, 16°18...
... Concentration column, 17 ... Mass flow meter, 21 ... Separation column, 23. Old ... Photometer with flow cell, 29 ... Cooling tank, 31 ...
... Heating container, 32 ... Heater, 33 ...
... Porous tube, 34 ... Cation exchange membrane, 35 ... Acid solution, 38 ... Cation exchange tube, 39 ... Teflon tube . Figure 1: Clara F° (sakai OL) Figure 2: Dissolution time (system) Figure 2: Figure 4 / /, 13: 3fffiK te;, ta: :@2 Column 21:S NfJ Lamb 23, Flow 7 Ruis Likelihood I Figure 3 to 20 P:I (No.) 5th Expansion Time No. Fig. 6 Fig. 7 mran (separate Fig. 8 Fig. 10 Fig. 38゛Cation exchange 4p + Euph'.

Claims (1)

[Claims] 1. A method for preliminarily dissolving insoluble fine particles in water in an ionic form and then separating and quantifying metal components contained therein,
After adding a solubilizing agent to the sample water and heating it to dissolve insoluble fine particles, a complex decomposer is added to decompose the dissolved complexes, equalize the metal ion valence, concentrate it in a concentration column, and separate each part in a separation column. A method for analyzing insoluble particulates in water, which comprises separating into components, adding a coloring agent, and measuring absorbance. 2. The method for analyzing insoluble fine particles in water according to claim 1, wherein the concentration using the concentration column concentrates only the metal ions without concentrating the solubilizing agent components. 3. The method for analyzing insoluble fine particles in water according to claim 1 or 2, characterized in that an organic acid is used as the dissolving agent. 4. The method for analyzing insoluble fine particles in water according to claim 1, 2 or 3, characterized in that an oxidizing agent or a reducing agent is used as the complex decomposer. 5. In a method of preliminarily dissolving insoluble fine particles in water into ionic form, and then separating and quantifying the metal components contained therein,
After adding hydrochloric acid as a dissolving agent to the sample water and heating it to dissolve insoluble fine particles, an oxidizing agent or reducing agent is added and heat treated to equalize the metal ion valence, and chloride ions are removed by electrodialysis. A method for analyzing insoluble particulates in water, which comprises adjusting the pH of the solution, concentrating it using a concentration column, separating it into each component using a separation column, adding a coloring agent, and measuring the absorbance. 6. Claims 1 to 6, characterized in that the organic acid used as the dissolving agent is heated with an oxidizing agent added thereto in advance, and then subjected to electrodialysis to remove impurities in the organic acid. The method for analyzing insoluble fine particles in water according to item 1 of item 4. 7. Among claims 1 to 5, the inorganic acid used as the solubilizer or complex decomposer is subjected to electrodialysis in advance to remove impurities in the inorganic acid. The method for analyzing insoluble particulates in water according to item 1. 8. Adding the inorganic acid from which impurities have been removed to the sample water by heating and vaporizing the inorganic acid used as the solubilizer or complex decomposer and adding it to the sample water through a porous tube that allows gas to pass through. A method for analyzing insoluble fine particles in water according to one of claims 1 to 5, characterized in that: 9. In an apparatus for preliminarily dissolving insoluble fine particles in water into ionic form and separating and quantifying the metal components contained therein, means for adding a solubilizing agent to the sample water and means for heating the solution to which the solubilizing agent has been added. a means for adding a decomposing agent to the solution; a means for concentrating metal ions in the solution; a means for dissolving and separating the concentrated metal ions; and a means for adding a coloring agent.
1. A device for analyzing insoluble particulates in water, comprising means for measuring absorbance. 10. The apparatus for analyzing insoluble fine particles in water according to claim 9, further comprising means for performing electrodialysis to adjust the pH of the solution to be concentrated.