JPH05256835A - Chromatograph - Google Patents

Abstract

PURPOSE:To reduce the size of a system and improve the safety of the system by reducing the cost and amount of waste liquids of ordinary chromatographic processes and the amounts of acid and alkali stored in the closed space of a spacecraft, etc. CONSTITUTION:This chromatograph is constituted of a separation column 101 which separates a plurality of useful materials from each other, removal column 104 which removes an eluate component from an eluate from the column 101, electric dialyzing section 106 which separates and regenerates the eluate component and regenerated solution component from the regenerated solution used as the regenerated solution of the column 104, electric conductivity meter 119 which detects the useful materials, and a plurality of valves 115 and 116 which separate the useful materials from each other in accordance with information from the meter 119.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chromatographic apparatus for separating a plurality of useful substances contained in a liquid by utilizing the difference in adsorptivity with respect to an adsorbent, and particularly to water treatment in a closed space such as a spacecraft. The present invention relates to an apparatus for separately collecting a plurality of useful substances from post-concentrated waste liquid.

[0002]

2. Description of the Related Art A plurality of useful substances are contained in concentrated waste liquid after wastewater treatment in an enclosed space system, and it is desirable to reuse these. Separation and recovery of potassium and sodium among them is considered to be difficult because the chemical properties of both substances are similar, and as shown in the paper "Closed ecosystem" of the Japan Aeronautical Society of Japan No. 376, there is a difference in solubility. Although a crystallization method utilizing EDTA and an ion chromatography method utilizing the difference in adsorptivity to an ion exchange membrane have been proposed, the problems of eluents have not been investigated.

Further, in the case of detecting the elution of a useful substance which is desorbed from the column also in a general chromatographic apparatus, the regenerant of the removal column, which removes the eluent in order to lower the background at the time of detection, together with the eluent. After use, it is simply discarded.

[0004]

When the above-mentioned potassium and sodium are separated and recovered, a large amount of acid is used as an eluent when the ion chromatography method is used (Japan Aerospace Society Journal No. 376, P288, "closed ecosystem"). According to the results of Bollow et al. Described above, it requires about 40 times as much hydrochloric acid as potassium and sodium to be separated).
Storing a large amount of acid in an enclosed space such as a spacecraft poses safety and space problems.

Further, in a general ion chromatograph used for separating a trace amount of substances, when a substance separated and eluted from a column is detected by an electric conductivity meter, a background due to an eluent component is reduced so that ion exchange is performed. An eluent component is adsorbed and removed by a removal column provided with a membrane, and the regenerant used for the regeneration of this removal column contains the eluent component desorbed from the column and is usually discarded as it is.

In the present invention, in the separation of potassium and sodium, the eluent is regenerated by electrodialysis or the eluent and the removal column regenerant are regenerated, and the storage amount of acid and alkali in a closed space such as a spacecraft is reduced. For the purpose of reducing and reducing the chromatographic apparatus for analysis in general, the eluent used for analysis can be obtained by continuously regenerating the used eluent and regenerant using electrodialysis and analyzing the ions. The purpose is to reduce the amount of liquid / regeneration liquid.

[0007]

In order to achieve the above-mentioned object, the present invention provides a device for separately collecting a plurality of useful substances in a liquid according to a difference in adsorptivity with respect to an adsorbent, wherein the useful substances are adsorbed and separated. A separation column packed with an adsorbent,
A means for supplying an eluent for desorbing the useful substance from the adsorbent to the separation column, a means for injecting a mixed solution of the useful substance to be treated into the eluent, and a method for injecting the useful substance from the separation column. Means for detecting elution by electrical conductivity, a removal column for removing components of the eluent in the eluate prior to detection, means for supplying a regenerant for regenerating the removal column to the removal column, the used An electrodialysis unit that separates and regenerates the eluent component and the regenerant component from the regenerant, and a unit that supplies the used regenerant from the removal column to the electrodialysis unit, and the regenerated eluent and the regenerant liquid. Is provided with an eluent supply means and a regenerant supply means, respectively.

Further, in an apparatus for separating and recovering a plurality of useful substances in a liquid according to the difference in adsorptivity to the adsorbent, a separation column filled with the adsorbent for adsorbing the useful substance, and the useful substance from the adsorbent Means for supplying an eluent for desorbing to the separation column and means for mixing the eluent with a mixed solution of the useful substance to be treated, wherein the eluate from the separation column is mixed with the useful substance and the eluent. Electrodialysis means for separating and concentrating into components, means for distributing to the electrodialysis means each of the useful substances containing the eluate from the separation column, collecting and storing the useful substances concentrated by each electrodialysis means And a means for reducing the eluent component regenerated by electrodialysis to a means for supplying the eluent to the column.

[0009]

By using the means according to the present invention, the storage amount of the acid / alkali used and the amount of the waste liquid can be reduced, so that the safety aspect in the closed space system can be improved, the waste of space can be omitted, and the processing cost can be reduced. It will be possible.

Further, by reducing the amounts of the eluent and the regenerant in a general chromatographic apparatus, it is possible to reduce the cost of analysis and the amount of waste liquid.

[0011]

Embodiments of the present invention will be described in detail with reference to FIGS.

FIG. 1 shows an example of an eluent / regeneration liquid regeneration type potassium / sodium fractional recovery ion chromatograph according to the present invention. This device is a chromatographic device that regenerates the regenerant and the eluent of the eluent removal column by using electrodialysis simultaneously with the ion analysis process. This apparatus comprises a separation column 101 for separating useful substances, a line 102 for supplying the separation column eluent, a line 103 for supplying a useful substance mixed liquid to be treated to the line 102, and an eluent component in the eluate from the column. Removal column 1
04, a line 105 for supplying a regenerant for regenerating the removal column, an electrodialysis tank 106 for separating a regenerant component and an eluent component from a used regenerant, a line 107 for supplying a used regenerant to the dialysis tank , And regenerant and eluent regenerated in the dialysis tank, respectively, regenerant supply line 10
5 and a line 108 for returning to the eluent supply line 102,
109, an electric conductivity meter 119 for detecting ions, and a valve 11 for sorting the detected useful substances by useful substances
5, 116, potassium recovery line 117, and sodium recovery line 118. The useful substance (potassium or sodium) separated by the separation column elutes in the state of a mixture with the eluent component, and therefore the background of the eluent component is unsuitable for detection by a conductivity meter, and the removal column At 104, the eluent component is removed and then detected. The detected useful substance is distributed by the valves 115 and 116 to the potassium or sodium recovery line according to the detection data and collected. At this time, in consideration of the capacity of the removal column, the regeneration solution (alkaline solution in this case) is passed through at the same time as the adsorption of the eluent to regenerate the column. In addition, since the eluent component desorbed from the removal column is included,
It is usually disposed of. In the present invention, at the same time as the separation process, the eluent and the regenerated liquid are separated and regenerated from the used regenerated liquid in the electrodialysis tank 106 having the ion exchange membrane, and these liquids are reused for the analytical treatment, thereby reducing the analysis cost. Aim to reduce the amount of waste liquid. For example, when sulfuric acid is used as the eluent and sodium hydroxide is used as the regenerant, the used regenerant 107 after regenerating the removal column 104 having the anion exchange membrane is a mixed solution of sodium sulfate and sodium hydroxide, This is passed through the electrodialysis tank 106, and the cathode 110 and the anode 111
When a voltage is applied to the sulfate ion, the sulfate ion moves to the eluent regeneration chamber 114 through the anion exchange membrane 112 and is combined with hydrogen ion in the water to be sulfuric acid. On the other hand, sodium ions, which are cations, cannot pass through the anion exchange membrane, and the regenerant regeneration chamber 1
It remains in 13 and combines with hydroxide ion in water to regenerate sodium hydroxide. Regeneration processing of these eluents / regeneration liquids shall be continuously performed in parallel with the separation analysis processing. Then, the regenerated sulfuric acid is reduced by the line 109 to the eluent supply line 102, and the similarly regenerated sodium hydroxide is reduced from the line 108 to the regenerant supply line 105 for reuse. As a result, the eluent / regeneration liquid can be used repeatedly, so that the processing cost can be reduced, and the amount of acid / alkali stored and the amount of waste liquid can be reduced, improving the safety in the enclosed space and downsizing the system. It will be possible.
In addition, this method of regenerating and reusing the eluent and the regenerant can be applied to general analytical chromatography.

FIG. 2 shows an example of the arrangement of ion exchange membranes in the electrodialysis tank of the eluent / regenerant regenerated ion chromatographic apparatus of the present invention. The unit cell of this device consists of two regenerant regeneration chambers and two eluent regeneration chambers, a total of four chambers.
-4 chambers, a cation exchange membrane is arranged between the first and second chambers, a third chamber and a fourth chamber, and a composite membrane is arranged between the second and third chambers. First, when the used regenerant solution is passed through the second and fourth chambers from the line 206 and an electric current is applied with the electrode 206 as a cathode and the electrode 207 as an anode, sodium ions in the used regenerant solution are converted into cation exchange membrane 201. , 203 to the first and third chambers, and the sulfate ion, which is an anion, is blocked by the cation exchange membrane and the composite membrane and remains in the second and fourth chambers. Therefore, sodium hydroxide is separated and regenerated in the first and third chambers and sulfuric acid is separated and regenerated in the second and fourth chambers. The regenerated sodium hydroxide is reduced from the line 209 to the regenerant supply line 104 in FIG. 1 and used again as a regenerant. Similarly, the regenerated sulfuric acid is reduced from the line 208 to the eluent supply line of FIG. 1 and reused as an eluent.

FIG. 3 shows an example of an eluent regeneration type chromatographic apparatus for separating potassium and sodium according to the present invention. This device has a separation column 301 for separating a plurality of useful substances, and an eluent (sulfuric acid here) in the separation column.
302 for supplying a mixture of useful substances to be treated to the eluent supply line, electrodialysis tanks 304, 305 for separating and concentrating the eluent components and useful substances from the eluate from the column, and the column 306, 307, 308 for allocating the eluate of (1) to the electrodialysis tank according to useful substances contained in the solution, and a line for reducing the eluent components regenerated in each electrodialysis tank to the eluent supply line 302 again. It is composed of 309 and 310. Here, a sodium-potassium mixed solution extracted from the concentrated wastewater after water treatment in the spacecraft is supplied to the eluent supply line 302 by line 3
It is injected from 03 and is passed through the separation column 301.
The potassium / sodium ions in the mixed solution are adsorbed by the monovalent selective ion exchange resin in the column and then desorbed by the eluent, but they are different because the desorption rate is different due to the difference in the adsorption property to the ion exchange membrane. It can be eluted and separated. This eluate is a separated useful substance and eluent component (sulfate ion)
Since it is a mixed liquid with the useful substance, it is distributed to the electrodialysis tank 304 or 305 depending on the type of the useful substance contained therein, and the useful substance and the eluent substance are separated there. Electrodialysis layer 30
4, 305 are anodes 311, 313 and cathode 31 respectively.
2, 314 with an ion exchange membrane. When the eluate is passed through the eluate regeneration chambers 317 and 319 of the electrodialysis layer, and a direct current voltage is applied to both electrodes to pass an electric current, potassium ions which are cations through the cation exchange membranes 315 and 316.
Sodium ions move to the cathode-side concentration chambers 318 and 320 and are concentrated. On the other hand, since the eluent component (sulfate ion) cannot pass through the cation exchange membrane, the eluent regeneration chamber 31
Remains at 7,319 and is combined with hydrogen ions in water to regenerate sulfuric acid. Regenerated sulfuric acid is in lines 309 and 3
It is reduced from 10 to the eluent supply line 302 and reused as an eluent. As a result, a small amount of eluent can be continuously used, and the storage amount of the eluent acid can be minimized.

FIG. 4 shows the eluent regenerating type potassium of the present invention.
The arrangement example of the ion exchange membrane of the electrodialysis tank of the sodium fractionation recovery ion chromatograph is shown. In this case, one cell has a four-chamber structure, and assuming that the chambers are the first to fourth chambers in order from the left side of the figure, the anion exchange membrane 401, between the first chamber and the second chamber,
The composite membrane 402 is arranged between the second chamber and the third chamber, and the anion exchange membrane 403 is arranged between the third chamber and the fourth chamber. The eluate 404 from the separation column is flowed into the first and third chambers,
When pure water or a part of the eluent in the eluent supply line is passed through the second chamber and the fourth chamber through the line 407 and a DC voltage is applied to the cathode 405 and the anode 406, the second chamber and the fourth chamber are eluted. Anions (sulfate ions) in the liquid move to regenerate and concentrate sulfuric acid. On the other hand, in the first chamber and the third chamber, the cations (potassium or sodium ions) in the eluate are blocked by the anion exchange membranes 401 and 403 and the composite membrane 402 and remain and are concentrated. The cations thus concentrated are in line 408.
The sulfuric acid that has been collected and stored for each ion and then regenerated is regenerated from the line 409 to the eluent supply line for reuse. As a result, the purity and concentration of the recovered potassium ion and sodium ion can be increased, and the amount of the eluent stored can be reduced by reusing and reusing the used eluent.

[0016]

The chromatographic apparatus according to the present invention can reduce the storage amount of acid / alkali and the amount of waste liquid produced in the closed space, so that the system can be downsized, the safety can be improved, and the processing cost can be reduced. is there.

Further, in the general analytical ion chromatography, the eluent and the regenerant can be repeatedly used, so that the analysis cost and the amount of waste liquid can be reduced.

[Brief description of drawings]

FIG. 1 is a system diagram of a chromatography device according to the present invention.

FIG. 2 is an explanatory diagram of an electrodialysis unit according to the present invention.

FIG. 3 is a system diagram of a chromatography device according to the present invention.

FIG. 4 is an explanatory diagram of an electrodialysis unit according to the present invention.

[Explanation of symbols]

101 ... Separation column, 102 ... Eluent supply line, 10
4 ... Removal column, 105 ... Regeneration liquid supply line, 106 ... Electrodialysis part, 108 ... Regeneration liquid reduction line, 109 ... Eluent reduction line, 110, 111 ... Electrode, 119 ... Electrical conductivity meter.

Claims (4)

[Claims] 1. An apparatus for separately collecting a plurality of useful substances in a liquid according to the difference in adsorptivity with respect to the adsorbent, and a separation column filled with the adsorbent for adsorbing / separating the useful substances; Means for supplying an eluent for desorbing a useful substance to the separation column, means for injecting a mixed solution of the useful substance to be treated into the eluent, and elution of the useful substance from the separation column with electric conductivity. Means for removing the components of the eluent in the eluent prior to detection, means for supplying a regenerant for regenerating the removal column to the removal column, and elution from the used regenerant An electrodialysis means for separating and regenerating a liquid component and the regenerated liquid component, a means for supplying the used regenerated liquid from the removal column to the electrodialysis means, and the regenerated eluent. Chromatographic apparatus characterized by comprising means for reducing said regenerant to each eluent feed means regeneration liquid supply means. 2. The method according to claim 1, further comprising means for sorting the detected useful substance according to the type of the useful substance, if necessary, to separate the useful substance by the separation column and to elute from the separation column. Detection of useful substances,
Distribution of the detected useful substance, removal of the eluent component in the eluate of the separation column by the removal column, regeneration of the removal column, and separation and regeneration of the eluent / regeneration liquid component from the regenerant component used in the removal column. , And a chromatography device that continuously reuses the regenerated eluent and regenerated liquid. 3. An apparatus for separating and recovering a plurality of useful substances in a liquid according to the difference in adsorptivity with respect to the adsorbent, a separation column filled with the adsorbent for adsorbing the useful substance, and the useful substance from the adsorbent. Means for supplying an eluent for desorbing to the separation column and means for mixing the eluent with a mixed solution of the useful substance to be treated, wherein the eluate from the separation column is mixed with the useful substance and the eluent. Electrodialysis means for separating and concentrating into components, means for distributing to the electrodialysis means each of the useful substances containing the eluate from the separation column, collecting and storing the useful substances concentrated by each electrodialysis means A chromatograph having means and means for reducing an eluent component regenerated by electrodialysis to a means for supplying an eluent to a column. 4. The supply of the eluent and the useful substance mixed solution to the separation column, the separation of the useful substance by the adsorbent, and the useful substance / eluent component separated and eluted from the separation column according to claim 3. Distribution of the mixed solution to the electrodialysis means for each useful substance, separation and concentration of the eluent component and the useful substance in the electrodialysis means, and recovery of the concentrated useful substance and regeneration eluent to the eluent supply means. Chromatography equipment that continuously supplies.