CN1665961A - Process for producing alkali metal chlorate - Google Patents
Process for producing alkali metal chlorate Download PDFInfo
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- CN1665961A CN1665961A CN03815960.0A CN03815960A CN1665961A CN 1665961 A CN1665961 A CN 1665961A CN 03815960 A CN03815960 A CN 03815960A CN 1665961 A CN1665961 A CN 1665961A
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- alkali metal
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/24—Halogens or compounds thereof
- C25B1/26—Chlorine; Compounds thereof
- C25B1/265—Chlorates
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/34—Simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine, e.g. by chlor-alkali electrolysis
- C25B1/46—Simultaneous production of alkali metal hydroxides and chlorine, oxyacids or salts of chlorine, e.g. by chlor-alkali electrolysis in diaphragm cells
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Abstract
The invention relates to a process for producing alkali metal chlorate in an electrolytic cell that is divided by a cation selective separator into an anode compartment in which an anode is arranged and a cathode compartment in which a gas diffusion electrode is arranged. The process comprises introducing an electrolyte solution containing alkali metal chloride into the anode compartment and an oxygen-containing gas into the cathode compartment. The invention also relates to an electrolytic cell for the production of alkali metal chlorate comprising a cation selective separator dividing the cell into an anode compartment in which an anode is arranged and a cathode compartment in which a gas diffusion electrode is arranged. An inlet for electrolyte solution and an outlet for electrolysed solution are provided in the anode compartment and an inlet for introducing oxygen-containing gas is provided in the gas chamber. The invention also relates to a plant comprising the electrolytic cell and the use thereof for the production of alkali metal chlorate and/or chlorine dioxide.
Description
The present invention relates to a process for the production of alkali metal chlorate, and an electrolytic cell and an apparatus for carrying out the process. The invention furthermore relates to the use of the electrolytic cell and the apparatus for the production of alkali metal chlorate and/or chlorine dioxide.
Background
Alkali metal chlorate, especially sodium chlorate, is an important chemical in the cellulose industry where it is used as a raw material in the production of chlorine dioxide, an important bleaching chemical for cellulose fibers. Alkali metal chlorate is usually produced by electrolysis of alkali metal chloride in an open non-isolated electrolytic cell equipped with a hydrogen evolving cathode. The overall chemical reaction taking place in such cells is Wherein Me is an alkali metal. The reaction has an electrolyzer voltage of 3V.
In the past, attempts have also been made to produce chlorate using electrolytic cells equipped with oxygen-consuming gas diffusion electrodes. The English chemical abstracts of Chinese patent application No.1076226 (AN 1994: 421025) discloses such AN electrolytic cell for the production of sodium chlorate. The gas diffusion electrode may reduce oxygen supplied to a gas chamber adjacent to the gas diffusion electrode. The reduction reaction at the gas diffusion electrode (gas diffusion cathode) is . The oxidation reaction at the anode is . The cell voltage for the total chemical reaction in this gas diffusion electrode cell is about 2V, which means that considerable operating costs can be saved by replacing the above-mentioned hydrogen evolving cathode with a gas diffusion electrode as cathode.
However, the operation of the cell disclosed in the english abstract of chinese patent application No.1076226 immediately leads to poisoning of the gas diffusion electrode, because of the reaction products HClO, ClO formed on the anode-And ClO3 -Will diffuse freely into the electrolyte and unwanted side reactions will inevitably occur at the gas diffusion electrode according to the following formula:
in many alkali metal chlorate processes, alkali metal chromates are used to inhibit reactions 1-3. However, alkali chromates also adversely affect the gas diffusion electrode, which rapidly deactivates when in contact with the chromate ions.
The production of chlorate may require large amounts of hydrochloric acid and alkali metal hydroxide, which also means considerable costs. Furthermore, the handling of these chemicals is complicated by the strict safety requirements involved in transport, storage and use.
It is an object of the present invention to overcome the above mentioned problems while providing an energy efficient electrolytic process for the production of alkali metal chlorate. It is another object of the invention to provide a process in which most of the added pH adjusting chemicals can be eliminated from the process.
The invention
The invention relates to a process for the production of alkali metal chlorate in an electrolytic cell which is divided by a cation selective separator into an anode compartment in which an anode is placed and a cathode compartment in which a gas diffusion electrode is placed. The process comprises introducing an electrolyte solution containing an alkali metal chloride into the anode chamber and introducing an oxygen-containing gas into the cathode chamber; electrolyzing the electrolyte solution to produce an electrolyzed solution in the anode compartment, the electrolysis of the oxygen introduced into the cathode compartment resulting in the formation of alkali metal hydroxide in the cathode compartment; the electrolyzed solution is transferred from the anode chamber to a chlorate reactor for reacting the electrolyzed solution to further form a concentrated alkali metal chlorate electrolyte.
In this process, the same cathode compartment space functions both as a gas chamber for oxygen-containing gas and as a chamber for alkali metal hydroxide production.
According to a preferred embodiment, the gas diffusion electrode is placed on the cation selective separator in order to minimize the ohmic resistance.
According to another preferred embodiment, the process is carried out in an electrolytic cell in which the gas diffusion electrode divides the cathodic compartment into a gas compartment on one side of the gas diffusion electrode and an alkali metal hydroxide compartment defined on the other side of the electrode between the gas diffusion electrode and a cation selective separator. The process includes introducing an electrolyte solution comprising an alkali chloride into the anode chamber, introducing an alkali hydroxide solution into an alkali hydroxide chamber and introducing an oxygen-containing gas into the gas chamber; thereby electrolyzing the electrolyte solution to produce an electrolyzed solution in the anode chamber, the electrolysis of the oxygen introduced into the gas chamber resulting in the formation of additional alkali metal hydroxide in the alkali metal hydroxide chamber; the electrolyzed solution is transferred from the anode chamber to a chlorate reactor for reacting the electrolyzed solution to further form a concentrated alkali metal chlorate electrolyte.
Preferably, a pressure of up to about 10 bar, preferably up to about 5 bar, may be applied to the cell. This can be achieved by applying a suitable overpressure to the oxygen-containing gas in the gas chamber and the inert gas in the anode chamber.
The cation selective separator is preferably substantially resistant to chlorine and alkali metal hydroxides, and enables efficient production of the electrolyzed solution and concentrated alkali metal hydroxide to occur with low levels of chlorate ions and chloride ions in the alkali metal hydroxide chamber. The cation selective separator is preferably a cation selective membrane. The cation selective membrane may suitably be made of an organic material, for example a fluoropolymer, such as a perfluorinated polymer. Other suitable membranes may be made from polyethylene, polypropylene and sulfonated polyvinyl chloride, polystyrene or teflon based polymers or ceramics. In addition, there are suitable usesCommercially available membranes such as Nafion manufactured by Du PontTM324，NafionTM550 and NafionTM961, and Flemion manufactured by Asahi GlassTM。
Suitably, a support may be placed on the anode and/or cathode side to support the cation selective separator.
The anode may be made of any suitable material, such as titanium. May be made of, for example, RuO2/TiO2Or Pt/Ir suitably coats the anode. The anode is preferably a DSA (dimensionally stable anode) with a expanded mesh substrate.
The gas diffusion electrode may be a liquid-leaking (weeping) gas diffusion electrode, a semi-hydrophobic gas diffusion electrode or any other gas diffusion electrode, such as those described in european patent applications No.01850109.8, No.00850191.8, No.00850219.7 and US patents US5,938,901 and US5,766,429. There is no particular limitation on the gas diffusion electrode. For example, a gas diffusion electrode comprising only a reaction layer and a gas diffusion layer may be used. The gas diffusion layer may be made of a mixture of carbon and PTFE resin. The reactive layer may suitably have a content of hydrophobic material such as fluorocarbon in order to maintain suitable water repellency and hydrophilicity. In addition, a protective layer may be formed on the surface of the gas diffusion layer to more effectively prevent the gas diffusion layer from becoming hydrophilic.
The process of the invention can be described as a cyclic process, since in the first step the electrolyte solution comprising the alkali chloride solution is passed into an electrolysis cell, wherein at least a part of the chloride is electrolyzed to form inter alia hypochlorite and chlorate. The electrolysed solution is suitably discharged to a conventional chlorate reactor, such as the reactor described in US5,419,818, for further reaction to produce chlorate. The chlorate reactor may comprise several chlorate vessels. The chlorate electrolyte may then be transferred to a crystalliser where the alkali metal chlorate in solid state is separated by crystallisation and the mother liquor containing inter alia unreacted chloride ions, hypochlorite,chlorate may be returned to the electrolytic cell for further electrolysis. It is also possible to use an alkali metal hydroxide scrubber as chlorate reactor, wherein chlorate is formed by reacting alkali metal hydroxide provided, for example, from an alkali metal hydroxide chamber with chlorine gas discharged from the anode chamber. According to a preferred embodiment, an alkali metal hydroxide scrubber to which chlorine gas is supplied and a chlorate reactor to which the electrolysed solution is supplied are used simultaneously in the process.
The concentrated chlorate electrolyte may comprise from about 200 to about 1200g/l, and preferably from about 650 to about 1200 g/l.
The electrolyte solution introduced into the anode compartment may suitably contain at least some chlorate, suitably in the range of from about 1 to about 1000g/l, preferably from about 300 to about 650g/l, and most preferably from about 500 to about 650g/l, calculated as sodium chlorate. Suitably, the electrolyte solution may contain chloride ions in a concentration range of about 30 to about 300g/l, preferably about 50 to about 250g/l, and most preferably about 80 to about 200g/l, calculated as sodium chloride.
According to another preferred embodiment, the concentration of chlorate in the electrolyte solution introduced into the anode compartment is from about 1 to about 50g/l, preferably from about 1 to about 30 g/l.
Suitably, the chlorine gas generated in the anode compartment is largely dissolved into the solution to be electrolysed. The dissolved chlorine undergoes automatic partial hydrolysis to form hypochlorous acid according to the following formula:
in a buffer or hydroxide ion (B)-) In the presence of (a) hypochlorous acid dissociates to hypochlorite according tothe formula:
the pH of the electrolyzed solution in the anode chamber is preferably above 4 in order to promote dissolution of chlorine. The electrolyzed solution containing chlorine and/or hypochlorous acid may be transferred to a chlorate reactor. A suitable range for the pH of the electrolyzed solution provided to the anode compartment is from about 2 to about 10, preferably from about 5.5 to about 8. A suitable range for the concentration of alkali metal hydroxide in the alkali metal hydroxide compartment is from about 10 to about 500g/l, preferably from about 10 to about 400g/l, more preferably from about 20 to about 400g/l, and most preferably from about 40 to about 160g/l, calculated as sodium hydroxide. The alkali metal hydroxide produced can be directly discharged or recycled to the alkali metal hydroxide chamber for further electrolysis until the desired concentration is reached. The alkali metal hydroxide produced may be used for alkalisation of the chlorate electrolyte in a chlorate reactor prior to crystallization of chlorate. The alkali metal hydroxide may also be used to precipitate hydroxides of alkaline earth metals, iron and aluminum in order to purify the new alkali metal chloride used in the electrolyte solution. It is also possible to use the alkali metal hydroxide for absorbing chlorine from the process outlet of the chlorate reactor and, as mentioned before, for absorbing chlorine discharged from the anode compartment for the direct production of alkali metal chlorate in the alkali metal hydroxide scrubber.
According to a preferred embodiment, an alkali metal chromate is added to the electrolyte solution as a pH buffer and suppresses unwanted reactions. Chromate is added in an amount of about 0.01 to about 10g/l, preferably up to about 6 g/l. According to another preferred embodiment, no chromate is added to the electrolyte solution.
A suitable range of temperature in the cell is from about 20 to about 105 c, preferably from about 40 to about 100 c.
The chlorate is preferably produced by a continuous process, but a discontinuous process may also be used. Preferably, the process of the invention can be combined with the production of chlorine dioxide, using chlorate electrolyte or alkali metal chlorate as starting material.
The invention also relates to an electrolytic cell for the production of alkali metal chlorate comprising a cation selective separator dividing the cell into an anode compartment in which an anode is positioned and a cathode compartment in which a gas diffusion electrode is positioned. An inlet for an electrolyte solution and an outlet for an electrolyzed solution are provided in the anode chamber, and an inlet for introducing an oxygen-containing gas is provided in the cathode chamber.
According to a preferred embodiment, the gas diffusion electrode is arranged on the separator in order to minimize the ohmic resistance.
According to another preferred embodiment, the gas diffusion electrode divides the cathode compartment into a gas compartment on one side of the gas diffusion electrode and an alkali metal hydroxide compartment on the other side of the electrode defined between the gas diffusion electrode and the cation selective separator. An inlet and an outlet for an alkali metal hydroxide solution are provided in the alkali metal hydroxide chamber.
Preferably, the cation selective separator may be any of the cation selective membranes described above. It is furthermore preferred to provide an outlet for the oxygen-containing gas in the gas chamber. Preferably a separate outlet for chlorine gas is provided in the anode compartment and/or the chlorate reactor. Chlorine gas may also leave the anode compartment through the outlet for the electrolyzed solution. According to one embodiment of the invention, the anode compartment is not provided with a separate chlorine outlet.
The structure of the above-described embodiment of the electrolytic cell is so robust that the electrolytic cell can withstand the flow and other physical conditions of electrolytes conventional in the field of chlorate production. Preferably, the cell is configured to withstand preferably at least about 0.5m in the anode and/or cathode compartments3h-1m-2More preferably at least about 1m3h-1m-2Still more preferably at least about 3m3h-1m-2And most preferably at least about 5m3h-1m-2. Preferably, the inlet and outlet are also designed so as to meet these conditions.
The invention furthermore relates to an apparatus comprising an electrolytic cell as described above, wherein the outlet of the anode compartment is suitably connected to the chlorate reactor via the outlet of the electrolyzed solution. The chlorate reactor may accordingly be connected to a crystallizer for transferring chlorate electrolyte, which can be precipitated in the crystallizer and separated from the mother liquor. The chlorate reactor may be suitably connected to the anode compartment so that part of the alkali metal chlorate electrolyte can be recycled to the anode compartment.
The apparatus may suitably comprise a storage vessel for alkali metal chloride and/or electrolyte treatment agent such as alkali metal chromate.
The reactor may also be an alkali metal hydroxide scrubber to which chlorine gas may be withdrawn from the anode compartment and reacted with alkali metal hydroxide to produce alkali metal chlorate. Suitably, an alkali metal hydroxide vessel may be connected to the alkali metal hydroxide chamber for providing and recycling alkali metal hydroxide. The container may be a suitable reservoir to which water and circulating alkali metal hydroxide may be continuously supplied to adjust the concentration of alkali metal hydroxide supplied to the alkali metal hydroxide chamber. The outlet of the alkali metal hydroxide chamber may be connected to several units for alkalization in the chlorate plant, e.g. to the inlet of an alkali metal hydroxide scrubber or other chlorate reactor, or to a crystallizer for transferring alkali metal hydroxide. Preferably, not only an alkali metal hydroxide scrubber but also a conventional chlorate reactor receiving the electrolyzed solution is arranged in the apparatus.
The invention also relates to the use of the electrolytic cell and the apparatus, including for the production of alkali metal chlorate, preferably sodium chlorate, further e.g. potassium chlorate. Sodium chlorate can be produced in the form of solid sodium chlorate salt or sodium chlorate electrolyte, which can be used for the production of chlorine dioxide, preferably by an on-site chlorine dioxide generator.
Brief Description of Drawings
FIG. 1 schematically illustrates an electrolytic cell according to one embodiment of the invention. Fig. 2 schematically illustrates a plant for the production of sodium chlorate according to the invention.
Description of the embodiments
Fig. 1 shows an electrolytic cell 1 for sodium chlorate production. The electrolytic cell comprises an anode chamber 2 in which an anode 2a is placed, a cation selective membrane 3, and a cathode chamber 5 partitioned by a gas diffusion electrode into an alkali metal hydroxide chamber 4 and a gas chamber 6. The inlet and outlet of sodium chloride and electrolyte in the anode compartment 2 are indicated by arrows 7. A separate outlet for chlorine gas (not shown) may be provided in the anode compartment. The inlet and outlet of sodium hydroxide in the alkali metal hydroxide chamber are indicated by arrows 8. The inlet and outlet of oxygen in the gas chamber 6 are indicated by arrows 9. Other configurations of the cell (not shown) include two separate cells, i.e., no separate gas chambers, in which the gas diffusion electrodes are positioned directly on the cation selective separator.
Fig. 2 schematically illustrates a plant for producing sodium chlorate. An electrolyte solution 7 containing sodium chloride and chlorate electrolyte obtained from a chlorate reactor 10 are introduced into the anode compartment 2 of the electrolytic cell 1. The electrolyte solution is electrolyzed to form an electrolyzed solution, which is pumped through the anode compartment 2 to the chlorate reactor 10 where chlorate continues to be formed. The chlorate electrolyte in the chlorate reactor 10 is alkalized with alkali hydroxide produced in the cathode compartment 4 before being discharged to the crystallizer 12 where sodium chlorate crystallizes. The chlorate electrolyte may also be discharged into a reaction vessel (not shown) for the production of chlorine dioxide. In the anode compartment 2, a certain amount of chlorine gas is generated during electrolysis. The chlorine gas produced can be transferred to a sodium hydroxide scrubber 11, where it is absorbed in sodium hydroxide, which can lead to the formation of sodium chlorate. The sodium hydroxide scrubber can therefore also be used as a sodium chlorate reactor. Sodium chloride may be added continuously to the electrolyte solution 7 prior to introduction into the anode compartment. Water may be continually added to the sodium hydroxide tank 4a to maintain the proper concentration of sodium hydroxide passing through the sodium hydroxide chamber. Sodium hydroxide may also be used in the crystallizer 12 for alkalization.
Example 1
The test was carried out in a discontinuous process with an initial volume of 2 litres for the reactor vessel. The initial concentration of electrolyte in the anode compartment was 110g NaCl per liter, 550g NaClO per liter3And 3gNa per liter2Cr2O7. The solution was pumped through the anode compartment of the cell at a rate of 25l/h, which corresponds to a linear velocity across the anode of approximately 2 cm/s. Linear speed across the cathode of 2cm/sA sodium hydroxide solution with a concentration of 50g/l was pumped through the cathode compartment. Excess oxygen is fed into the gas chamber. The cell was a pilot cell comprising an anode chamber having a Dimensionally Stable (DSA) chlorine anode and a cathode chamber having a non-catalytic carbon loaded (5-6 mg/cm) cathode chamber2) The silver-plated nickel wire gas diffusion electrode. The area of each electrode was 21.2cm2. The anode and cathode chambers are separated by a cation selective membrane, Nafion450Spaced apart and the distance between each electrode and the membrane was 8 mm.
At 0.71 g.a-1h-1The solid sodium chloride is fed into the reactor vessel and into the anode chamber to maintain the concentration of sodium chloride in the reactor vessel constant. At 0.5 ml.ampere-1min-1Water was added to the cathode chamber at a rate to maintain the concentration of sodium hydroxide constant. At a temperature of 70 ℃ of 0.2-3kA/m2And a pH of 6.2 in the electrolytic cell. The current varied between 0.5-6.3A. The electrolysis was carried out for 30 h.
The current efficiency of the electrolysis was 92% calculated on hydroxide ions produced in the cathode compartment. The current efficiency was calculated as the quotient of the actual and theoretical maximum production of sodium hydroxide. The hydroxide ion production was determined by analyzing the hydroxide ion content of the catholyte and multiplying it by the collected flow rate. NaClO formed in the anode compartment according to the whole electrolysis process3To calculate the NaClO3The yield of (2). It is estimated that the current efficiency for chlorine formation is close to 100%. The current efficiency for chlorate production is 95% calculated as the quotient of the actual recovered and the theoretical maximum production of sodium chlorate.
Example 2
The test was carried out in a discontinuous process with a starting volume of 2 litres for the reactor vessel. The initial concentration of electrolyte in the anode compartment was 110g NaCl per liter, 550g NaClO per liter3And 3gNa per liter2Cr2O7. The solution was pumped through the anode compartment of the cell at a rate of 25l/h, which corresponds to a linear velocity across the cathode of approximately 2 cm/s. Excess oxygen is passed into the gas chamber. The cell was a pilot cell comprising an anode chamber with a Dimensionally Stable (DSA) chlorine anode and a cathode chamber with a gas diffusion electrode made of silver, PTFE and carbon on silver mesh (screen). The area of each electrode was 21.2cm2. The anode compartment and the gas diffusion electrode are separated by a cation selective membrane (Nafion 450). The distance between the anode and the membrane was 8 mm. There is no distance between the membrane and the gas diffusion electrode. To be provided with0.71g*A-1h-1The solid sodium chloride is fed into the reactor vessel and into the anode chamber to maintain the concentration of sodium chloride in the reactor vessel constant. At a temperature of 70 ℃ of 0.2-3kA/m2And a pH of 6.2 at the electric currentAnd electrolyzing in the electrolytic bath. The current varied between 0.5-6.3A. The electrolysis was carried out for 30 h. NaClO formed in the anode compartment according to the whole electrolysis process3Total amount calculation of NaClO3The yield of (2). It is estimated that the current efficiency for chlorine formation is close to 100%. The current efficiency for chlorate production was 97% calculated as the quotient of the actual recovered and the theoretical maximum production of sodium chlorate.
Claims (23)
1. Process for the production of alkali metal chlorate in an electrolytic cell (1) divided by a cation selective separator (3) into an anode compartment (2) in which an anode (2a) is positioned and a cathode compartment (5) in which a gas diffusion electrode (5a) is positioned, said process comprising introducing an electrolyte solution comprising alkali metal chloride into the anode compartment (2) and introducing an oxygen containing gas into the cathode compartment (5); electrolyzing the electrolyte solution to produce an electrolyzed solution in the anode compartment (2), electrolyzing oxygen introduced into the cathode compartment (5) resulting in the formation of alkali metal hydroxide in the cathode compartment (5); the electrolyzed solution is transferred from the anode chamber (2) to a chlorate reactor (10, 11) for reacting the electrolyzed solution to further produce a concentrated alkali metal chlorate electrolyte.
2. A process according to claim 1, wherein the gas diffusion electrode (5a) divides the cathode compartment (5) into a gas chamber (6) on one side of the gas diffusion electrode (5a) and an alkali metal hydroxide chamber (4) on the other side of the electrode defined between the gas diffusion electrode (5a) and the cation selective separator (3), an alkali metal hydroxide solution being introduced into the alkali metal hydroxide chamber (4) and an oxygen-containing gas being introduced into the gas chamber (6).
3. A process according to claim 1 or any one of the preceding claims, wherein the cation selective separator (3) is a cation selective membrane.
4. A process as claimed in any one of the preceding claims, wherein the electrolyte solution has a pH of from about 5.5 to about 8.
5. A process as claimed in any one of the preceding claims, wherein the electrolyte solution has an alkali chloride concentration of from about 50 to about 250 g/l.
6. A process as claimed in any one of the preceding claims, wherein the electrolyte solution introduced into the anode compartment (2) has a concentration of alkali metal chlorate of from about 300 to about 650 g/l.
7. A process as claimed in any one of the preceding claims, wherein the electrolyte solution has an alkali metal chlorate concentration of from about 1 to about 50 g/l.
8. A process as claimed in any one of the preceding claims, wherein the electrolyte solution has an alkali chromate concentration of about 0.01 to about 10 g/l.
9. A process as claimed in any one of the preceding claims, wherein the electrolyte solution does not contain an alkali metal chromate.
10. A process as claimed in any one of claims 1 to 9 wherein the cathode compartment has an alkali metal hydroxide concentration of from about 10 to about 400 g/l.
11. A process as claimed in any one of the preceding claims, wherein the electrolytic cell (1) has a temperature of from about 40 to about 100 ℃.
12. The process as claimed in any of the preceding claims, wherein alkali metal hydroxide is transferred from the alkali metal hydroxide chamber (4) to the chlorate reactor (10, 11).
13. An electrolytic cell (1) for the production of alkali metal chlorate, the electrolytic cell comprisingA cation selective separator (3) dividing the electrolytic cell (1) into an anode chamber (2) in which an anode (2a) is disposed and a cathode chamber (5) in which a gas diffusion electrode (5a) is disposed, an inlet for an electrolyte solution and an outlet for a solution to be electrolyzed being provided in the anode chamber (2), and an inlet for introducing an oxygen-containing gas being provided in the cathode chamber (5), wherein the electrolytic cell can withstand at least about 0.5m3h-1m-2The flow rate through the anode chamber.
14. An electrolytic cell (1) according to claim 13, wherein said gas diffusion electrode (5a) divides the cathode compartment (5) into a gas chamber (6) on the side of the gas diffusion electrode (5a) and an alkali metal hydroxide chamber (4) defined between the gas diffusion electrode (5a) and the cation selective separator (3) on the other side thereof, an inlet and an outlet for the alkali metal hydroxide being provided in the alkali metal hydroxide chamber (4), and an inlet for introducing the oxygen-containing gas being provided in the gas chamber (6).
15. An electrolytic cell (1) according to either one of claims 13 or 14, wherein the cation selective separator (3) is a cation selective membrane.
16. An electrolysis cell (1) according to any of claims 13 to 15 wherein a separate outlet for chlorine gas is provided in the anode compartment (2).
17. A cell (1) according to any one of claims 13 to 16 wherein no outlet for chlorine gas is provided in the anode compartment (2).
18. A cell (1) according to any one of claims 13 to 17 wherein an outlet for oxygen containing gas is provided in the cathode compartment (5).
19. An apparatus comprising an electrolytic cell (1) according to any one of claims 13-18, wherein the electrolytic cell (1) is connected to the chlorate reactor (10, 11) through an outlet of the anode compartment (2)
20. The apparatus according to claim 19, wherein the reactor (10, 11) has an outlet for the alkali metal chlorate electrolyte connected to the crystallizer (12).
21. An apparatus according to claims 19-20, wherein the alkali metal chlorate reactor (10, 11) is connected to the anode compartment (2) so that part of the alkali metal chlorate solution can be recycled to the anode reaction chamber (2).
22. An apparatus according to any one of claims 19 to 21, which comprises a storage vessel for alkali metal chloride and/or electrolyte treatment reagents.
23. Use of an electrolytic cell (1) according to any one of claims 13-18, or an apparatus according to any one of claims 19-22, for the production of alkali metal chlorateand/or chlorine dioxide.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP02445094.2 | 2002-07-05 | ||
| EP02445094 | 2002-07-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1665961A true CN1665961A (en) | 2005-09-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN03815960.0A Pending CN1665961A (en) | 2002-07-05 | 2003-06-19 | Process for producing alkali metal chlorate |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP1527209A1 (en) |
| CN (1) | CN1665961A (en) |
| AU (1) | AU2003239065B2 (en) |
| BR (1) | BR0312387B1 (en) |
| CA (1) | CA2490737A1 (en) |
| RU (1) | RU2317351C2 (en) |
| WO (1) | WO2004005583A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107004929A (en) * | 2014-08-19 | 2017-08-01 | 乔米莱曼 | The method for storing the electrochemical appliance and production hydrogen of electric energy and production hydrogen |
| CN109415823A (en) * | 2016-06-24 | 2019-03-01 | 东亚合成株式会社 | The method of operation of alkali metal hydroxide manufacturing device and alkali metal hydroxide manufacturing device |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8034227B2 (en) | 2005-06-30 | 2011-10-11 | Akzo Nobel N.V. | Chemical process |
| ITMI20061374A1 (en) * | 2006-07-14 | 2008-01-15 | Uhdenora Spa | CHLORINE-SODA ELECTROLYZER EQUIPPED WITH OXYGEN DIFFUSION CATHODE |
| DE102009023539B4 (en) * | 2009-05-30 | 2012-07-19 | Bayer Materialscience Aktiengesellschaft | Method and device for the electrolysis of an aqueous solution of hydrogen chloride or alkali chloride in an electrolytic cell |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL256163A (en) * | 1959-09-28 | |||
| US4269675A (en) * | 1978-07-13 | 1981-05-26 | The Dow Chemical Company | Electrolyte series flow in electrolytic chlor-alkali cells |
| US4364805A (en) * | 1981-05-08 | 1982-12-21 | Diamond Shamrock Corporation | Gas electrode operation |
| FR2691479B1 (en) * | 1992-05-20 | 1994-08-19 | Atochem Elf Sa | Method of manufacturing alkali metal chlorate and device for its implementation. |
| BR9401547A (en) * | 1993-04-26 | 1994-11-22 | Eka Nobel Ab | Process for the production of alkali metal chlorate |
| JP3553775B2 (en) * | 1997-10-16 | 2004-08-11 | ペルメレック電極株式会社 | Electrolyzer using gas diffusion electrode |
| JP3437127B2 (en) * | 1999-07-07 | 2003-08-18 | 東亞合成株式会社 | Operating method of alkaline chloride electrolytic cell |
-
2003
- 2003-06-19 AU AU2003239065A patent/AU2003239065B2/en not_active Ceased
- 2003-06-19 CA CA002490737A patent/CA2490737A1/en not_active Abandoned
- 2003-06-19 RU RU2005102827/15A patent/RU2317351C2/en not_active IP Right Cessation
- 2003-06-19 WO PCT/SE2003/001062 patent/WO2004005583A1/en not_active Application Discontinuation
- 2003-06-19 BR BRPI0312387-1A patent/BR0312387B1/en not_active IP Right Cessation
- 2003-06-19 EP EP03733780A patent/EP1527209A1/en not_active Withdrawn
- 2003-06-19 CN CN03815960.0A patent/CN1665961A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107004929A (en) * | 2014-08-19 | 2017-08-01 | 乔米莱曼 | The method for storing the electrochemical appliance and production hydrogen of electric energy and production hydrogen |
| CN107004929B (en) * | 2014-08-19 | 2020-10-23 | 乔米莱曼 | Electrochemical device for storing electric energy and producing hydrogen and method for producing hydrogen |
| CN109415823A (en) * | 2016-06-24 | 2019-03-01 | 东亚合成株式会社 | The method of operation of alkali metal hydroxide manufacturing device and alkali metal hydroxide manufacturing device |
| CN109415823B (en) * | 2016-06-24 | 2021-02-26 | 东亚合成株式会社 | Alkali metal hydroxide production apparatus and method for operating alkali metal hydroxide production apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| RU2005102827A (en) | 2005-08-20 |
| BR0312387A (en) | 2005-04-12 |
| RU2317351C2 (en) | 2008-02-20 |
| WO2004005583A1 (en) | 2004-01-15 |
| AU2003239065B2 (en) | 2009-01-08 |
| AU2003239065A1 (en) | 2004-01-23 |
| CA2490737A1 (en) | 2004-01-15 |
| BR0312387B1 (en) | 2013-05-14 |
| EP1527209A1 (en) | 2005-05-04 |
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