CA1056764A - Method for producing hydrogen peroxide - Google Patents
Method for producing hydrogen peroxideInfo
- Publication number
- CA1056764A CA1056764A CA243,512A CA243512A CA1056764A CA 1056764 A CA1056764 A CA 1056764A CA 243512 A CA243512 A CA 243512A CA 1056764 A CA1056764 A CA 1056764A
- Authority
- CA
- Canada
- Prior art keywords
- hydroxide
- alkaline earth
- earth metal
- hydrogen peroxide
- peroxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- 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
- C25B1/28—Per-compounds
- C25B1/30—Peroxides
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Hydrogen peroxide is produced by an improved process in which an aqueous solution of alkali metal hydroxide and hydroperoxide is formed by electrolytic decomposition of aqueous alkali metal hydroxide solution with concurrent feeding of oxygen through a gas electrode cathode. The solution of alkali metal hydroxide and hydroperoxide is treated with alkaline earth metal hydroxide to form alkaline earth metal hydroperoxide which is repre-cipitated as alkaline earth metal carbonate by contact with carbon dioxide and with the simultaneous formation of hydrogen peroxide. The process functions in good yield and employs readily available raw materials without giving rise to harmful by-products.
Hydrogen peroxide is produced by an improved process in which an aqueous solution of alkali metal hydroxide and hydroperoxide is formed by electrolytic decomposition of aqueous alkali metal hydroxide solution with concurrent feeding of oxygen through a gas electrode cathode. The solution of alkali metal hydroxide and hydroperoxide is treated with alkaline earth metal hydroxide to form alkaline earth metal hydroperoxide which is repre-cipitated as alkaline earth metal carbonate by contact with carbon dioxide and with the simultaneous formation of hydrogen peroxide. The process functions in good yield and employs readily available raw materials without giving rise to harmful by-products.
Description
~05676A
The invention relates to a method for producing hydrogen peroxide, according to which an aqueous solution containing an alkali metal hydroxide and an alkali metal hydroperoxide is formed by electrolytic decomposition of an aqueous alkali metal hydroxide solution with concurrent feeding of oxygen through the cathode, which is in the form of a gas electrode.
Hydrogen peroxide has many technological applications, for example as an oxidizing agent and also for producing peroxides. It is also used in the paper-making and textile industries as a bleaching agent.
In one known process for producing hydrogen peroxide, sulphuric acid or an ammonium sulphate solution is anodically oxidi7ed in an electroly-sis cell to form peroxy disulphuric acid or a peroxy disulphate, which is then hydrolytically decomposed at increased temperatures. The resulting hydrogen peroxide is separated from the other products of the reaction by vacuum distillation. However, the disadvantage of this process is that it requires consumption of relatively large amounts of power. In addition to this, the aggressiveness of the medium, and the necessary very positive anode potential, mean that the anodes must be made of highly resistant material, platinum being practically the only material that can be used for these anodes. Finally, corrosion arising from hydrolytic decomposition in this known process, and the need for separation from the hot sulphuric acid by distillation, make high demands on the material used for the equipment for carrying out the process.
Also known is a method whereby hydrogen peroxide is produced in addition to the quinone formed by oxidizing hydroquinones with atmospheric oxygen. Although this method does not have the disadvantages of the electro-lytic process method above, it has the disadvantage that the catalysts used in the necessary recovery of the hydroquinone by hydrating the quinone are not sufficiently selective. In this method, the said catalysts are suspended in the reaction solution and they can only be made of very expensive metals such as platinum, raney nickel, or the like. As a result, the method is very costly. In addition, prior to oxidizing the hydroquinone, the catalysts suspended in the solution must be separated from the working solution. This makes the method cumbersome and, since it also produces by-products, laborious cleaning operations are required in order to remove the hydrogen peroxide from the reaction process which operates in a circuit.
Also known is a method according to which hydrogen peroxide is produced by cathodic reduction of oxygen, using an aqueous solution of potas-sium chloride as the electrolyte liquid. According to this method, the electrolyte liquid containing the hydroperoxide ions is removed from the electrolysis and neutralized with hydrochloric acid, the hydrogen peroxide thus formed being recovered by distillation (cf. ~. Berl, Trans. Electrochem.
Soc. 76 (1939), page 359). This method, however, has been found unsuitable for practical purposes, since the presence of chloride ions in the electro-lyte liquid resulted in highly inefficient distillation, thus making the recovery of hydrogen peroxide unecono~ical.
It is the purpose of the invention to provide a method for the production of hydrogen peroxide which is not only easy to carry out but also ensures a high yield. This method is rendered even more economical by the fact the raw materials used are easily obtainable and there are no harmful by-products.
Accordingly, the invention provides a method for producing hydrogen peroxide, which comprises forming an aqueous solution containing an alkali hydroxide and an alkali hydroperoxide by the electrolytic decomposi-tion of an aqueous alkali-hydroxide solution while feeding of oxygen through the cathode which is in the form of a gas electrode, treating the aqueous solution with a concentrated alkaline earth metal hydroxide solution, or a suspension of alkaline earth metal hydroxide in water, or solid alkaline-earth metal hydroxide or oxide, so as to form alkaline earth metal perox-ide, lOS6764 and reprecipitating this peroxide as aIkaline earth metal carbonate with simultaneous formation of hydrogen peroxide, by reacting an aqueous suspension of the peroxide with carbon dioxide and separating the hydrogen peroxide.
Thus,the alkaline earth metal peroxide formed by the reaction of the aIkaline earth metal hydroxide and ~he alkali metal hydroperoxide is drawn off, after precipitation and filtering out of the aIkali hydroxide formed at the same time and contained in the aqueous solution, is suspended in water, and is reprecipitated as alkaline earth metal carbonate by introducing carbon dioxide, with simultaneous formation of hydrogen peroxide, the alkaline earth metal carbonate then being filtered out and drawn off.
The hydrogen peroxide is present dissolved in water. Thus, with the method according to the invention, although the hydrogen peroxide appears dissolved in water, there is no contamination by by-products. The desired concentration is easily obtained by distillation. When compared with the yield, the power consumed in carrying out the method according to the inven-tion is low. Another considerable advantage is that relatively inexpensive materials may be used for the electrocles. If potassium hydroxide is used as the aIkaline-earth metal hydroxide, this produces a highly economical method, since adequate quantities of potassium hydroxide are available in the form of slaked lime. Still another advantage of the method according to the in~ention is that any calcium carbonate arising can be calcined into calcium oxide which produces carbon dioxide. This carbon dioxide may be utilized in carrying out the method according to the invention. The resulting calcium oxide is suspended in water and may also be circulated in the form of cal-cium hydroxide.
In the method according to the invention, it is preferable that the alkali metal compound used be potassium hydroxide, since potassium peroxide does not crystallize out of the solution onto the cathode. The advantage of this is the cathode remains serviceable over relatively long pericds of time. According to an advantageous embodiment of the method according to the invention, the solution containing alkali metal hydroxide formed by filtering out and drawing off the alkaline earth metal peroxide can be returned to the electrolysis cell. The advantage of this is that the alkali metal hydroxide produced in the method according to the invention may be reused in the said method, making it still more economical, Sodium hydroxide can also be used as the aIkali metal hydroxide, while calcium and magnesium hydroxides are examples of suitable alkaline earth metal hydroxides.
An embodiment of the method of the invention will now be described by way of example with reference to the drawing which is a flow chart.
Referring to the drawing, an aqueous potassium-hydroxide solution is fed into an anode chamber 1 of an electrolysis cell 4 divided by a diaphragm 2, into the anode chamber 1 and a cathode chamber 3. The oxygen formed on the anode la is removed from the upper part of the anode chamber and may be passed to a cathode 5 located in the cathode chamber 3.
Oxygen or air is fed from above, under slight positive pressure, to the cathode 5, which is in the form of a gas electrode. Any unused oxygen or air is drawn off again from the upper part of the cathode chamber 3. Potassium hydroperoxide formed by reaction in the electrolysis cell 4, and the potassium hydroxide also produced, are passed to a container 6, con-nected to the electrolysis cell 4, and mixed therein with calcium hydroxide.
The potassium peroxide thus formed is filtered out by filter 7 and is passed to a pressure-tight reaction vessel 8. The filtrate consisting of potassium-hydroxide solution, is returned to the anode chamber of the electrolysis cell 4. In the reaction vessel 8, the peroxide is suspended in water and mixed under pressure with carbon dioxide, the calcium peroxide being repre-cipitated as calciwm carbonate. The suspension is then filtered out by means of a filter 9 disposed in the reaction vessel 8. The filtrate thus lOS6764 produced is an aqueous solution of hydrogen peroxide. If necessary, this may be concentrated by distillation (not shown in the flow chart3. It is also possible (but not shown in the chart) to calcine the calcium carbonate left as a residue during filtration, whereby to form calcium oxide and thus to release carbon dioxide. The calcium oxide and carbon dioxide thus obtained may be used again in carrying out the method.
EXample For the purpose of producing hydrogen peroxide, use was made of an electrolysis cell divided into an anode and a cathode chamber by a diaphragm made of porous polyvinyl chlorideO The electrode area was about 50 cm . The amount of electrolyte liquid passing through the cell was about 40 litres of liquid per square metre of electrode area per hour. The electro-lyte liquid passed to the anode chamber was a four molar potassium-hydroxide solution. The difference between the level of the solution in the anode chamber and that in the cathode chamber was such that the amount of solution corresponding to the throughput flowed through the said diaphragm into the cathode chamber.
The voltage between the anode and cathode was maintained at 2,4 V, the resulting current density amounting to approximately 2000 amps/m of electrode area.
Oxygen formed on the graphite anode was removed from the top of the anode chamber. Oxygen at a positive pressure of about 0.1 atm. was fed to the cathode, the active constituent of which consisted of activated charcoal, bonded with rubber, of a quality suitable for the formation of hydrogen peroxide. The amount of oxygen supplied, when converted, was approximately 1250 litres/m of electrode area/hour, this being about 1.5 times the amount that could theoretically be consumed. The excess oxygen was used to mix the solution in the cathode chamber and to accelerate the releaseof heat from the solution to a coil carrying cooling waterO This produced a cathode chamber temperature of between 20 and 25 C, which largely prevented any automatic decomposition of the hydrogen peroxide. The tempera-ture in the anode chamber adjusted itself to about 50 C.
An aqueous suspension of calcium hydroxide in an approximately stoichiometric volume was added to the electrolyte solution containing potassium hydroxide and potassium hydroperoxide, removed from the cathode chamber. The amount of calcium hydroxide needed for this amounted, when converted, to about 2,78 kg/m2 of electrode area/hour. Some calcium per-oxide, containing a small amount of calcium hydroxide, was precipitated. In relation to the current flowing, the amount of calcium peroxide corresponded to a yield of about 90~ of the theoretically possible amount. The re-formed four molar potassium-hydroxide solution filtered out of the precipitate was returned to the anode chamber of the electrolysis cell.
The calcium peroxide obtained as a filtration residue was suspend-ed in a pressure-tight reaction vessel with about 20 litres of water/m of electrode area/hour, the said suspension being mixed with carbon dioxide gas at a pressure of 7 atm. This reprecipitated the calcium peroxide, and the small amount of calcium hydroxide present, as calcium carbonate, whereupon the suspension was filteredO The filtrate was a dilute solution of 5% hydro-gen peroxide by weight in water. The calcium carbonate obtained as a filtra-tion residue was discarded. The amount of hydrogen peroxide formed corres-ponded to a yield of 82~ in relation to the closed flow.
The invention relates to a method for producing hydrogen peroxide, according to which an aqueous solution containing an alkali metal hydroxide and an alkali metal hydroperoxide is formed by electrolytic decomposition of an aqueous alkali metal hydroxide solution with concurrent feeding of oxygen through the cathode, which is in the form of a gas electrode.
Hydrogen peroxide has many technological applications, for example as an oxidizing agent and also for producing peroxides. It is also used in the paper-making and textile industries as a bleaching agent.
In one known process for producing hydrogen peroxide, sulphuric acid or an ammonium sulphate solution is anodically oxidi7ed in an electroly-sis cell to form peroxy disulphuric acid or a peroxy disulphate, which is then hydrolytically decomposed at increased temperatures. The resulting hydrogen peroxide is separated from the other products of the reaction by vacuum distillation. However, the disadvantage of this process is that it requires consumption of relatively large amounts of power. In addition to this, the aggressiveness of the medium, and the necessary very positive anode potential, mean that the anodes must be made of highly resistant material, platinum being practically the only material that can be used for these anodes. Finally, corrosion arising from hydrolytic decomposition in this known process, and the need for separation from the hot sulphuric acid by distillation, make high demands on the material used for the equipment for carrying out the process.
Also known is a method whereby hydrogen peroxide is produced in addition to the quinone formed by oxidizing hydroquinones with atmospheric oxygen. Although this method does not have the disadvantages of the electro-lytic process method above, it has the disadvantage that the catalysts used in the necessary recovery of the hydroquinone by hydrating the quinone are not sufficiently selective. In this method, the said catalysts are suspended in the reaction solution and they can only be made of very expensive metals such as platinum, raney nickel, or the like. As a result, the method is very costly. In addition, prior to oxidizing the hydroquinone, the catalysts suspended in the solution must be separated from the working solution. This makes the method cumbersome and, since it also produces by-products, laborious cleaning operations are required in order to remove the hydrogen peroxide from the reaction process which operates in a circuit.
Also known is a method according to which hydrogen peroxide is produced by cathodic reduction of oxygen, using an aqueous solution of potas-sium chloride as the electrolyte liquid. According to this method, the electrolyte liquid containing the hydroperoxide ions is removed from the electrolysis and neutralized with hydrochloric acid, the hydrogen peroxide thus formed being recovered by distillation (cf. ~. Berl, Trans. Electrochem.
Soc. 76 (1939), page 359). This method, however, has been found unsuitable for practical purposes, since the presence of chloride ions in the electro-lyte liquid resulted in highly inefficient distillation, thus making the recovery of hydrogen peroxide unecono~ical.
It is the purpose of the invention to provide a method for the production of hydrogen peroxide which is not only easy to carry out but also ensures a high yield. This method is rendered even more economical by the fact the raw materials used are easily obtainable and there are no harmful by-products.
Accordingly, the invention provides a method for producing hydrogen peroxide, which comprises forming an aqueous solution containing an alkali hydroxide and an alkali hydroperoxide by the electrolytic decomposi-tion of an aqueous alkali-hydroxide solution while feeding of oxygen through the cathode which is in the form of a gas electrode, treating the aqueous solution with a concentrated alkaline earth metal hydroxide solution, or a suspension of alkaline earth metal hydroxide in water, or solid alkaline-earth metal hydroxide or oxide, so as to form alkaline earth metal perox-ide, lOS6764 and reprecipitating this peroxide as aIkaline earth metal carbonate with simultaneous formation of hydrogen peroxide, by reacting an aqueous suspension of the peroxide with carbon dioxide and separating the hydrogen peroxide.
Thus,the alkaline earth metal peroxide formed by the reaction of the aIkaline earth metal hydroxide and ~he alkali metal hydroperoxide is drawn off, after precipitation and filtering out of the aIkali hydroxide formed at the same time and contained in the aqueous solution, is suspended in water, and is reprecipitated as alkaline earth metal carbonate by introducing carbon dioxide, with simultaneous formation of hydrogen peroxide, the alkaline earth metal carbonate then being filtered out and drawn off.
The hydrogen peroxide is present dissolved in water. Thus, with the method according to the invention, although the hydrogen peroxide appears dissolved in water, there is no contamination by by-products. The desired concentration is easily obtained by distillation. When compared with the yield, the power consumed in carrying out the method according to the inven-tion is low. Another considerable advantage is that relatively inexpensive materials may be used for the electrocles. If potassium hydroxide is used as the aIkaline-earth metal hydroxide, this produces a highly economical method, since adequate quantities of potassium hydroxide are available in the form of slaked lime. Still another advantage of the method according to the in~ention is that any calcium carbonate arising can be calcined into calcium oxide which produces carbon dioxide. This carbon dioxide may be utilized in carrying out the method according to the invention. The resulting calcium oxide is suspended in water and may also be circulated in the form of cal-cium hydroxide.
In the method according to the invention, it is preferable that the alkali metal compound used be potassium hydroxide, since potassium peroxide does not crystallize out of the solution onto the cathode. The advantage of this is the cathode remains serviceable over relatively long pericds of time. According to an advantageous embodiment of the method according to the invention, the solution containing alkali metal hydroxide formed by filtering out and drawing off the alkaline earth metal peroxide can be returned to the electrolysis cell. The advantage of this is that the alkali metal hydroxide produced in the method according to the invention may be reused in the said method, making it still more economical, Sodium hydroxide can also be used as the aIkali metal hydroxide, while calcium and magnesium hydroxides are examples of suitable alkaline earth metal hydroxides.
An embodiment of the method of the invention will now be described by way of example with reference to the drawing which is a flow chart.
Referring to the drawing, an aqueous potassium-hydroxide solution is fed into an anode chamber 1 of an electrolysis cell 4 divided by a diaphragm 2, into the anode chamber 1 and a cathode chamber 3. The oxygen formed on the anode la is removed from the upper part of the anode chamber and may be passed to a cathode 5 located in the cathode chamber 3.
Oxygen or air is fed from above, under slight positive pressure, to the cathode 5, which is in the form of a gas electrode. Any unused oxygen or air is drawn off again from the upper part of the cathode chamber 3. Potassium hydroperoxide formed by reaction in the electrolysis cell 4, and the potassium hydroxide also produced, are passed to a container 6, con-nected to the electrolysis cell 4, and mixed therein with calcium hydroxide.
The potassium peroxide thus formed is filtered out by filter 7 and is passed to a pressure-tight reaction vessel 8. The filtrate consisting of potassium-hydroxide solution, is returned to the anode chamber of the electrolysis cell 4. In the reaction vessel 8, the peroxide is suspended in water and mixed under pressure with carbon dioxide, the calcium peroxide being repre-cipitated as calciwm carbonate. The suspension is then filtered out by means of a filter 9 disposed in the reaction vessel 8. The filtrate thus lOS6764 produced is an aqueous solution of hydrogen peroxide. If necessary, this may be concentrated by distillation (not shown in the flow chart3. It is also possible (but not shown in the chart) to calcine the calcium carbonate left as a residue during filtration, whereby to form calcium oxide and thus to release carbon dioxide. The calcium oxide and carbon dioxide thus obtained may be used again in carrying out the method.
EXample For the purpose of producing hydrogen peroxide, use was made of an electrolysis cell divided into an anode and a cathode chamber by a diaphragm made of porous polyvinyl chlorideO The electrode area was about 50 cm . The amount of electrolyte liquid passing through the cell was about 40 litres of liquid per square metre of electrode area per hour. The electro-lyte liquid passed to the anode chamber was a four molar potassium-hydroxide solution. The difference between the level of the solution in the anode chamber and that in the cathode chamber was such that the amount of solution corresponding to the throughput flowed through the said diaphragm into the cathode chamber.
The voltage between the anode and cathode was maintained at 2,4 V, the resulting current density amounting to approximately 2000 amps/m of electrode area.
Oxygen formed on the graphite anode was removed from the top of the anode chamber. Oxygen at a positive pressure of about 0.1 atm. was fed to the cathode, the active constituent of which consisted of activated charcoal, bonded with rubber, of a quality suitable for the formation of hydrogen peroxide. The amount of oxygen supplied, when converted, was approximately 1250 litres/m of electrode area/hour, this being about 1.5 times the amount that could theoretically be consumed. The excess oxygen was used to mix the solution in the cathode chamber and to accelerate the releaseof heat from the solution to a coil carrying cooling waterO This produced a cathode chamber temperature of between 20 and 25 C, which largely prevented any automatic decomposition of the hydrogen peroxide. The tempera-ture in the anode chamber adjusted itself to about 50 C.
An aqueous suspension of calcium hydroxide in an approximately stoichiometric volume was added to the electrolyte solution containing potassium hydroxide and potassium hydroperoxide, removed from the cathode chamber. The amount of calcium hydroxide needed for this amounted, when converted, to about 2,78 kg/m2 of electrode area/hour. Some calcium per-oxide, containing a small amount of calcium hydroxide, was precipitated. In relation to the current flowing, the amount of calcium peroxide corresponded to a yield of about 90~ of the theoretically possible amount. The re-formed four molar potassium-hydroxide solution filtered out of the precipitate was returned to the anode chamber of the electrolysis cell.
The calcium peroxide obtained as a filtration residue was suspend-ed in a pressure-tight reaction vessel with about 20 litres of water/m of electrode area/hour, the said suspension being mixed with carbon dioxide gas at a pressure of 7 atm. This reprecipitated the calcium peroxide, and the small amount of calcium hydroxide present, as calcium carbonate, whereupon the suspension was filteredO The filtrate was a dilute solution of 5% hydro-gen peroxide by weight in water. The calcium carbonate obtained as a filtra-tion residue was discarded. The amount of hydrogen peroxide formed corres-ponded to a yield of 82~ in relation to the closed flow.
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method for producing hydrogen peroxide, which comprises forming an aqueous solution containing an alkali hydroxide and an alkali hydroperoxide by the electrolytic decomposition of an aqueous alkali-hydroxide solution while feeding of oxygen through the cathode which is in the form of a gas electrode, treating the aqueous solution with a concentrated alkaline earth metal hydroxide solution, or a suspension of alkaline earth metal hydroxide in water, or solid alkaline earth metal hydroxide or oxide, so as to form alkaline earth metal peroxide, and reprecipitating this peroxide as alkaline earth metal carbonate with simultaneous formation of hydrogen peroxide, by reacting an aqueous suspension of the peroxide with carbon dioxide and separating the hydrogen peroxide.
2. A method according to claim 1, wherein potassium hydroxide is used as the alkali metal hydroxide.
3. A method according to claim 1 or 2, wherein calcium oxide or hydroxide is used as the alkaline earth metal oxide or hydroxide.
4. A method according to claim 1 or 2, wherein the solution formed by filtering out and drawing off the alkaline earth metal peroxide and con-taining alkali metal hydroxide is returned to the electrolysis step.
5. A method according to claim 1 or 2, wherein the oxygen formed on the anode of the electrolysis cell is used as a portion of the oxygen fed to the cathode.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2501342A DE2501342C3 (en) | 1975-01-15 | 1975-01-15 | Process for the production of hydrogen peroxide |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1056764A true CA1056764A (en) | 1979-06-19 |
Family
ID=5936462
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA243,512A Expired CA1056764A (en) | 1975-01-15 | 1976-01-14 | Method for producing hydrogen peroxide |
Country Status (10)
| Country | Link |
|---|---|
| JP (1) | JPS5835271B2 (en) |
| BE (1) | BE837300A (en) |
| CA (1) | CA1056764A (en) |
| CH (1) | CH595460A5 (en) |
| DE (1) | DE2501342C3 (en) |
| FR (1) | FR2297929A1 (en) |
| GB (1) | GB1529382A (en) |
| IT (1) | IT1079101B (en) |
| NL (1) | NL177701C (en) |
| SE (1) | SE7513805L (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4317349C1 (en) * | 1993-05-25 | 1994-10-13 | Metallgesellschaft Ag | Process for preparing alkali metal peroxide/percarbonate solutions |
| DE19516304C1 (en) * | 1995-05-04 | 1996-07-25 | Metallgesellschaft Ag | Economical prepn. of alkali peroxide hydrate useful as oxidant and bleach |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2331296C3 (en) * | 1973-06-20 | 1976-01-02 | Kernforschungsanlage Juelich Gmbh, 5170 Juelich | Process for the production of hydrogen peroxide |
| DE2453739C3 (en) * | 1974-11-13 | 1980-03-27 | Kernforschungsanlage Juelich Gmbh, 5170 Juelich | Process for the production of hydrogen peroxide |
-
1975
- 1975-01-15 DE DE2501342A patent/DE2501342C3/en not_active Expired
- 1975-11-18 NL NLAANVRAGE7513441,A patent/NL177701C/en not_active IP Right Cessation
- 1975-12-05 CH CH1583575A patent/CH595460A5/xx not_active IP Right Cessation
- 1975-12-08 SE SE7513805A patent/SE7513805L/en unknown
-
1976
- 1976-01-05 BE BE163302A patent/BE837300A/en not_active IP Right Cessation
- 1976-01-09 FR FR7600477A patent/FR2297929A1/en active Granted
- 1976-01-14 CA CA243,512A patent/CA1056764A/en not_active Expired
- 1976-01-14 GB GB1469/76A patent/GB1529382A/en not_active Expired
- 1976-01-14 JP JP51002889A patent/JPS5835271B2/en not_active Expired
- 1976-01-14 IT IT19230/76A patent/IT1079101B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| NL177701C (en) | 1985-11-01 |
| NL177701B (en) | 1985-06-03 |
| SE7513805L (en) | 1976-07-16 |
| DE2501342C3 (en) | 1979-05-17 |
| BE837300A (en) | 1976-05-03 |
| JPS5835271B2 (en) | 1983-08-01 |
| DE2501342B2 (en) | 1978-09-14 |
| FR2297929B1 (en) | 1979-08-31 |
| FR2297929A1 (en) | 1976-08-13 |
| GB1529382A (en) | 1978-10-18 |
| JPS5196797A (en) | 1976-08-25 |
| NL7513441A (en) | 1976-07-19 |
| IT1079101B (en) | 1985-05-08 |
| DE2501342A1 (en) | 1976-07-22 |
| CH595460A5 (en) | 1978-02-15 |
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