ZA200209366B - Method for making anhydrous sodium perchlorate. - Google Patents
Method for making anhydrous sodium perchlorate. Download PDFInfo
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- ZA200209366B ZA200209366B ZA200209366A ZA200209366A ZA200209366B ZA 200209366 B ZA200209366 B ZA 200209366B ZA 200209366 A ZA200209366 A ZA 200209366A ZA 200209366 A ZA200209366 A ZA 200209366A ZA 200209366 B ZA200209366 B ZA 200209366B
- Authority
- ZA
- South Africa
- Prior art keywords
- sodium perchlorate
- anhydrous sodium
- process according
- crystals
- silica
- Prior art date
Links
- 229910001488 sodium perchlorate Inorganic materials 0.000 title claims description 62
- BAZAXWOYCMUHIX-UHFFFAOYSA-M sodium perchlorate Chemical compound [Na+].[O-]Cl(=O)(=O)=O BAZAXWOYCMUHIX-UHFFFAOYSA-M 0.000 title claims description 61
- 238000000034 method Methods 0.000 title claims description 16
- 239000013078 crystal Substances 0.000 claims description 43
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 28
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 27
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 claims description 15
- 239000000377 silicon dioxide Substances 0.000 claims description 14
- XTEGARKTQYYJKE-UHFFFAOYSA-M Chlorate Chemical compound [O-]Cl(=O)=O XTEGARKTQYYJKE-UHFFFAOYSA-M 0.000 claims description 13
- 238000005868 electrolysis reaction Methods 0.000 claims description 13
- 239000000725 suspension Substances 0.000 claims description 10
- VLTRZXGMWDSKGL-UHFFFAOYSA-M perchlorate Inorganic materials [O-]Cl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-M 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 238000001704 evaporation Methods 0.000 claims description 6
- 230000008020 evaporation Effects 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 claims description 5
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 4
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 4
- 238000010586 diagram Methods 0.000 claims description 4
- 229910052708 sodium Inorganic materials 0.000 claims description 4
- 239000011734 sodium Substances 0.000 claims description 4
- 238000010936 aqueous wash Methods 0.000 claims description 3
- 238000002425 crystallisation Methods 0.000 claims description 3
- 230000008025 crystallization Effects 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 230000002209 hydrophobic effect Effects 0.000 claims description 2
- 239000011780 sodium chloride Substances 0.000 claims description 2
- 238000007738 vacuum evaporation Methods 0.000 claims description 2
- 239000000243 solution Substances 0.000 description 18
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 14
- 238000001914 filtration Methods 0.000 description 9
- 239000007787 solid Substances 0.000 description 9
- 239000007864 aqueous solution Substances 0.000 description 5
- 238000003860 storage Methods 0.000 description 5
- 238000005406 washing Methods 0.000 description 5
- 238000001816 cooling Methods 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 2
- -1 chlorate ions Chemical class 0.000 description 2
- YADSGOSSYOOKMP-UHFFFAOYSA-N dioxolead Chemical compound O=[Pb]=O YADSGOSSYOOKMP-UHFFFAOYSA-N 0.000 description 2
- 239000008151 electrolyte solution Substances 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000001117 sulphuric acid Substances 0.000 description 2
- 235000011149 sulphuric acid Nutrition 0.000 description 2
- 239000004698 Polyethylene Substances 0.000 description 1
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 150000004683 dihydrates Chemical class 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 150000004682 monohydrates Chemical class 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- AIUIJBDEQKTMHT-UHFFFAOYSA-N perchloric acid;hydrate Chemical compound O.OCl(=O)(=O)=O AIUIJBDEQKTMHT-UHFFFAOYSA-N 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 239000012429 reaction media Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 235000019333 sodium laurylsulphate Nutrition 0.000 description 1
- IXGNPUSUVRTQGW-UHFFFAOYSA-M sodium;perchlorate;hydrate Chemical compound O.[Na+].[O-]Cl(=O)(=O)=O IXGNPUSUVRTQGW-UHFFFAOYSA-M 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B11/00—Oxides or oxyacids of halogens; Salts thereof
- C01B11/16—Perchloric acid
- C01B11/18—Perchlorates
-
- 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
-
- 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
- C25B15/00—Operating or servicing cells
- C25B15/08—Supplying or removing reactants or electrolytes; Regeneration of electrolytes
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Description
® 1
The present invention relates to a process for the manufacture of anhydrous sodium perchlorate.
It is known to manufacture sodium perchlorate by electrolysis of an aqueous chlorate solution of the said metal in a single electrolytic stage or a succession of individual electrolytic stages. Reference may be made, on this subject, to Patents EP 368 767,
US 3 518 180 and US 3 475 301.
Thus, Patent EP 368 767 discloses a . 10 continuous process for the manufacture of sodium g perchlorate by electrolysis in a single stage of an electrolyte (liquid comprising sodium chlorate and sodium perchlorate in the dissolved state) kept uniform with a stationary composition, which composition is chosen so that it can directly deposit, by cooling, perchlorate crystals in a monohydrate, dihydrate or anhydrous form.
It is also indicated that, on conclusion of the electrolysis stage, the aqueous sodium perchlorate solution is crystallized by cooling or evaporation of water.
In Example 2 of Patent US 3 518 180, the electrolytic cell fed with a solution comprising 300 g/l of sodium chloride and 700 g/l of sodium perchlorate produces, at the outlet, a solution comprising 80 g/l of sodium chlorate and 1100 g/l of sodium perchlorate. After settling in an intermediate tank, this solution is subsequently evaporated to e 2 result in a suspension of crystals which is then centrifuged to give perchlorate crystals. No information is given regarding the nature of the perchlorate or the evaporation conditions.
Furthermore, the process for the manufacture of sodium perchlorate by oxidation of sodium chlorate, disclosed in Patent US 3 038 782, is carried out in the presence of lead dioxide in a reaction medium comprising sulphuric acid. After the electrolysis ~. 10 stage, the aqueous perchlorate solution is freed from ” lead-based compounds by filtration at approximately 90-100°C and then evaporated at 150°C and subsequently the concentrated aqueous solution comprising 1.32 mol of sodium perchlorate, 2.96 mol of perchloric acid, 0.12 mol of sulphuric acid and 8.45 mol of water is cooled to 25°C to give, after filtration, 0.92 mol of sodium perchlorate crystals accompanied by 0.08 mol of perchloric acid and 0.15 mol of water. The perchloric acid is subsequently removed by neutralization to finally give anhydrous sodium perchlorate comprising approximately 3.3% by weight of water, which, after drying at 105-100°C, results in dry anhydrous sodium perchlorate.
The Applicant Company has now found that the crystallization of anhydrous sodium perchlorate under specific conditions makes it possible to obtain crystals with a high degree of purity.
® 3
A first subject-matter of the present invention is a process for the manufacture of anhydrous sodium perchlorate, according to which an aqueous sodium perchlorate solution, originating directly from an electrolysis stage or from a succession of individual electrolytic stages on an aqueous chlorate solution of the said metal, is subjected to vacuum evaporation at a temperature of between 52 and 75°C, preferably of between 60 and 70°C. The absolute . 10 pressure is preferably between approximately 1500 and - 7000 Pa.
The aqueous sodium perchlorate solution is advantageously chosen so that the anhydrous sodium perchlorate can be isolated directly by crystallization, that is to say a solution which deposits the anhydrous sodium perchlorate by evaporation of water or by cooling; reference may be made, on this subject, to the work published under the direction of Paul Pascal, Nouveau Traité de Chimie
Minerale [New Treatise on Inorganic Chemistry], 1966,
Volume II, Part 1, p. 353 and Figure 37, which shows the NaClO; - NaClO; - H,0 ternary diagram.
The composition of this aqueous solution is preferably that which lies within the region of the
NaCl04 - NaClO; - H;0 ternary diagram delimited by the points: A: 58 g of NaClO;, 270 g of NaClO4; B: 87 g of
NaCl0;, 295 g of NaClOg, C: 280 g of NaClOs and D: 300 g of NaClO4 per 100 g of water.
® 4
The aqueous sodium perchlorate solution, originating from the electrolysis of an aqueous sodium chlorate solution, can be obtained by keeping the concentration of the sodium chlorate and of the sodium perchlorate constant in the single electrolysis stage by continuous addition of sodium chlorate and water simultaneously, each in an amount equal respectively to the amount of sodium chlorate and to the amount of water which, in the free state or in the combined form, . 10 are withdrawn continuously from the said stage. - Sodium bichromate can be added to the electrolytic solution to inhibit cathodic side reactions, such as, for example, the reduction of hypochlorite and chlorate ions.
The temperature of the electrolysis is generally between 40 and 90°C and the pH of the electrolytic solution is between 6 and 10.
Platinum-based anodes are advantageously used.
After the evaporation stage, the suspension of anhydrous sodium perchlorate crystals is filtered and then the crystals can subsequently be washed with water to remove the residual impurities.
The Applicant Company has noticed that, when the aqueous wash liquor is brought to a temperature of between 55 and 80°C, preferably of between 55 and 65°C, the washed crystals are composed essentially of anhydrous sodium perchlorate (devoid of sodium
® 5 perchlorate monohydrate) and exhibit good flowability.
In addition, the degree of purity of the anhydrous sodium perchlorate is improved.
The anhydrous sodium perchlorate crystals, thus filtered and washed, generally comprise 1 to 2% by weight of water.
A simplified diagram of a specific embodiment of the invention is given in Figure 1. A crystallizer 1, fed with aqueous sodium perchlorate solution ~. 10 originating directly from the electrolysis of sodium . chlorate 2, is placed under vacuum and then heated to a temperature of between 52 and 75°C. The evaporated water 3 leaves the crystallizer and a suspension of anhydrous sodium perchlorate crystals is withdrawn via 4. This suspension is subsequently filtered in 5 and wet anhydrous sodium perchlorate crystals are recovered in 6 and the filtrate is recovered in 7. According to an alternative form, after filtering, the anhydrous sodium perchlorate crystals can be washed with water brought to a temperature of 55-80°C.
According to another specific embodiment of the invention (Figure 2), a crystallizer 1 equipped with an elutriation leg 4 is fed continuously with aqueous sodium perchlorate solution originating directly from the electrolysis of sodium chlorate 2.
The crystallizer, placed under vacuum, is heated to and maintained at a temperature of between 52 and 75°C. The
® 6 suspension of the anhydrous sodium perchlorate crystals is subsequently withdrawn in 5 and then filtered in 6.
The wet anhydrous sodium perchlorate crystals are recovered in 7 and can optionally be washed. The aqueous filtration solution 8 can be recycled to the electrolysis and can optionally be injected into the crystallizer in 9.
The choice of the throughput of the loop for recirculation of the aqueous sodium perchlorate . 10 solution of the crystallizer and that of the g elutriation throughput injected in 9 make it possible, by regulating the amount of water evaporated in 3, to obtain the desired size of the crystals.
Another aim of the invention is the production of anhydrous sodium perchlorate crystals which retain good flowability over time. This aim can be achieved by subjecting the filtered (washed or unwashed) anhydrous sodium perchlorate crystals to a drying stage until a residual water content of less than 0.1% by weight and preferably of less than or equal to 0.05% by weight is obtained.
The drying stage can be carried out at a temperature of between 60 and 150°C and for a period of time of between 10 minutes and 1 hour.
Fluidized bed drying is preferred and the temperature is preferably between 100 and 150°C for a period of time of between 15 and 45 minutes in a batchwise process.
: o i
It is also possible to operate with continuous drying.
The Applicant Company has also noticed that the addition of a sufficient amount of finely divided silica to the filtered (washed or unwashed) anhydrous perchlorate crystals, preferably the crystals obtained after filtering and washing, makes it possible to obtain anhydrous sodium perchlorate crystals which retain good flowability over time. . 10 These anhydrous perchlorate crystals have - good flowability even after storage for a few months.
The amount of silica charged generally depends on its nature. An amount of silica of between 0.05 and 0.5% by weight with respect to the anhydrous sodium perchlorate crystals has given highly advantageous results.
Although it is possible to use silica with a hydrophilic nature, it is generally preferable to use hydrophobic silica. The specific surface area of the silica is advantageously between 100 and 300 ml/g.
The addition of the silica to the anhydrous sodium perchlorate crystals can be easily carried out in a mixer, for example a rotary mixer.
The present invention also relates to the anhydrous sodium perchlorate crystals thus obtained.
i. ( .
EXPERIMENTAL PART
~ Example 1
A crystallizer with a capacity of one litre is fed, with a throughput of 300 cm®/h, with an aqueous solution comprising 1100 g/1 of sodium perchlorate and 115 g/1 of sodium chlorate originating directly from a sodium chlorate electrolytic cell.
The crystallizer is placed under an absolute pressure of 5000 Pa and brought to and then maintained at a temperature of 65°C. Under these conditions, to maintain a constant level in the crystallizer, 70 g/h of water are evaporated and a suspension is withdrawn comprising 20 to 30% by weight of anhydrous sodium perchlorate crystals in the form of slightly agglomerated rods with a size of 500 x 100 um.
The suspension is subsequently filtered and then the filter residue is washed with water brought to 65°C.
After filtering, the anhydrous sodium perchlorate crystals comprise 0.8% by weight of sodium chlorate and, after washing, the sodium chlorate content in the crystals is less than 0.2%.
Residual water is present at approximately 2% by weight. - Example 2
A 20 nm’ crystallizer, maintained under an absolute pressure of 4000 Pa and at a temperature of
. ( . 65°C, is continuously fed, via the recirculation loop, with an aqueous sodium perchlorate solution originating from a stage of electrolysis of sodium chlorate and comprising 1110 g/l of perchlorate and 124 g/l of chlorate.
The throughputs for feeding with aqueous sodium perchlorate solution, for evaporating water and for withdrawing suspension via the elutriation leg are adjusted so as to obtain a level of solids of approximately 15% by weight in the crystallizer and 30% by weight in the elutriation leg.
The composition of the aqueous solution in the crystallizer is 295 g of sodium perchlorate and 34 g of sodium chlorate per 100 g of water.
A residence time of the solid in the crystallizer of 5 to 6 h and that of the liquid of approximately 10 h makes it possible to produce approximately 1.2 t/h of dry anhydrous sodium perchlorate.
The suspension withdrawn from the elutriation leg is subsequently filtered and then the filtered residue is washed with water brought to 65°C. The Cr’ content in the crystals after filtering is 7 ppm and, after washing, this content is reduced to less than 1 ppm.
The chlorate (Cl0;") content present in the crystals after filtering is 0.3% by weight and that after washing is less than 0.05% by weight.
od 10
The residual water content in the washed crystals is approximately 1 to 1.5% by weight.
The anhydrous sodium perchlorate crystals have a particle size of 800 um in the elutriation leg. - Example 3
The processing is carried out as described in
Example 2 but with an aqueous wash liquor brought to 35°C. The result of this is that the crystals set solid g 10 during the washing, which even results in the ’ filtration device becoming blocked. - Example 4
The processing is carried out as in Example 1 but while maintaining the crystallizer at 32°C and at an absolute pressure of 500 Pa. Under these conditions, sodium perchlorate monohydrate crystals are obtained. - Example 5 700 g of anhydrous sodium perchlorate crystals originating from Example 1 are introduced into a fluidized bed maintained at 140°C. After 40 minutes, the residual water concent is only 0.05% by weight.
This product retains very good flowability after storage for one month.
- Example 6
Drying is carried out under the same conditions as those described in Example 5 but with 50 kg of anhydrous sodium perchlorate crystals originating from Example 2.
A residual water content of approximately 0.05% by weight is obtained. - Examples 7-11 . 10 50 kg of sodium perchlorate crystals prepared - according to Example 2 are charged to a rotary mixer, they are then stirred for 1 hour and then silica is added over 10 to 15 minutes. Stirring is maintained for 30 to 40 minutes after the addition.
Finally, the resulting solid is packaged in a polyethylene bag and then enclosed in a 50 kg keg for 6 months.
After 3 or 6 months, on opening the keg, the solid retains perfect flowability (see Table I). - Example 12
The sodium perchlorate crystals prepared according to Example 2 and bagged up directly, then enclosed in a keg, set solid after storage for three months.
od 12 - Example 13
The processing is carried out as in Example 7 except that, instead of the silica, 200 ppm of triethanolamine, in the form of an aqueous solution prepared beforehand by dissolution of 10 g in 150 g of water, are added over 10 to 15 minutes.
After opening the keg after storage for three months, the solid has set solid. . 10 - Example 14 “ The processing is carried out as described in
Example 13 except that 200 ppm of sodium dodecyl sulphate are added instead of triethanolamine.
After storage for three months, it is observed, on opening the keg, that the product has set solid.
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Claims (12)
1. Process for the manufacture of anhydrous sodium perchlorate, according to which an aqueous sodium perchlorate solution, originating directly from an electrolysis stage or from a succession of individual electrolytic stages on an aqueous chlorate solution of the said metal, is subjected to vacuum evaporation at a temperature of between 52 and 75°C, . 10 preferably of between 60 and 70°C. g |
2. Process according to Claim 1, characterized in that the absolute pressure is between 1500 and 7000 Pa.
3. Process according to Claim 1 or 2, characterized in that the agueous sodium perchlorate solution is chosen so that the anhydrous sodium perchlorate can be isolated directly by crystallization.
4. Process according to Claim 3, characterized in that the composition of the aqueous sodium perchlorate solution lies within the region of the NaClO; - NaClO; - HO ternary diagram delimited by the points: A: 58 g of NaCl0O;, 270 g of NaClO. B: 87 g of NaClO:, 295 g of NaCloO, C: 280 g of NaCl, D: 300 g of NaClQO, per 100 g of water.
5. Process according to any one of Claims 1 to 4, characterized in that, on conclusion of the od 15 evaporation stage, the suspension of the anhydrous sodium perchlorate crystals is filtered and then the crystals are optionally washed with water.
6. Process according to Claim 5, characterized in that the temperature of the aqueous wash liquor is between 55 and 80°C, preferably between 55 and 65°C.
7. Process according to Claim 5 or 6, characterized in that the filtered anhydrous sodium . 10 perchlorate crystals are subsequently subjected to a “ drying stage until a residual water content of less than 0.1% by weight and preferably of less than or equal to 0.05% by weight is obtained.
8. Process according to Claim 5 or 6, characterized in that a sufficient amount of finely divided silica is added to the filtered anhydrous sodium perchlorate crystals.
9. Process according to Claim 8, characterized in that the amount of silica added is between 0.05 and 0.5% by weight with respect to the anhydrous sodium perchlorate crystals.
10. Process according to Claim 8 or 9, characterized in that the silica is a hydrophobic silica.
11. Process according to any one of Claims 8 to 10, characterized in that the specific surface area of the silica is between 100 and 300 m‘/g.
12. Anhydrous sodium perchlorate crystals which are capable of being obtained according to any cne of Claims 7 to 11.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR0007847A FR2810308B1 (en) | 2000-06-20 | 2000-06-20 | PROCESS FOR PRODUCING ANHYDROUS SODIUM PERCHLORATE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| ZA200209366B true ZA200209366B (en) | 2003-10-16 |
Family
ID=8851439
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| ZA200209366A ZA200209366B (en) | 2000-06-20 | 2002-11-18 | Method for making anhydrous sodium perchlorate. |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US20040011663A1 (en) |
| EP (1) | EP1292532B1 (en) |
| JP (1) | JP4113428B2 (en) |
| KR (1) | KR100498836B1 (en) |
| CN (1) | CN1212967C (en) |
| AU (1) | AU2001262472A1 (en) |
| BR (1) | BR0111783A (en) |
| FR (1) | FR2810308B1 (en) |
| MX (1) | MXPA02012876A (en) |
| NO (1) | NO20025703L (en) |
| TW (1) | TWI234545B (en) |
| WO (1) | WO2001098203A1 (en) |
| ZA (1) | ZA200209366B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080057071A1 (en) * | 2003-10-20 | 2008-03-06 | Watkins David N | Use Of Hedgehog Pathway Inhibitors In Small-Cell Lung Cancer |
| WO2010109922A1 (en) | 2009-03-26 | 2010-09-30 | 株式会社Ihi | Method and apparatus for producing perchlorate |
| CN101941679A (en) * | 2010-10-15 | 2011-01-12 | 茂县鑫盐化工有限公司 | Method for producing sodium chlorate through low-temperature vacuum evaporation and crystallization |
| US10457716B2 (en) | 2014-08-06 | 2019-10-29 | University Of Notre Dame Du Lac | Protein folding and methods of using same |
| CN105116970B (en) * | 2015-09-24 | 2018-08-21 | 环旭电子股份有限公司 | Seat is expanded in lateral docking |
| KR101926619B1 (en) | 2018-03-29 | 2018-12-11 | 금호석유화학 주식회사 | A copolymer comprising a functional monomer and a method for manufacturing the same |
| CN110835096B (en) * | 2019-11-28 | 2023-01-06 | 江西赣锋锂业股份有限公司 | Method for preparing high-purity anhydrous lithium perchlorate by using battery-grade lithium hydroxide monohydrate |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL129924C (en) * | 1964-10-12 | 1970-06-15 | ||
| US3475301A (en) * | 1964-11-25 | 1969-10-28 | Hooker Chemical Corp | Electrolytic preparation of perchlorates |
| FR2638766B1 (en) * | 1988-11-09 | 1990-12-14 | Atochem | CONTINUOUS PROCESS FOR THE MANUFACTURE OF ALKALINE METAL PERCHLORATE |
| SE463626B (en) * | 1988-12-28 | 1990-12-17 | Eka Nobel Ab | PROCEDURE FOR REDUCING PERCLORATE CONTENT IN ELECTROLYTES FOR CHLORATE PREPARATION |
| DE4001247A1 (en) * | 1990-01-18 | 1991-07-25 | Bayer Ag | Improving free-flowing properties of dimerised 2,4-TDI - by adding 0.01-10 wt. per cent pptd. or pyrogenic silica with hydrophobic surface |
-
2000
- 2000-06-20 FR FR0007847A patent/FR2810308B1/en not_active Expired - Fee Related
-
2001
- 2001-05-21 US US10/311,747 patent/US20040011663A1/en not_active Abandoned
- 2001-05-21 BR BR0111783-1A patent/BR0111783A/en active Search and Examination
- 2001-05-21 JP JP2002503649A patent/JP4113428B2/en not_active Expired - Fee Related
- 2001-05-21 MX MXPA02012876A patent/MXPA02012876A/en active IP Right Grant
- 2001-05-21 KR KR10-2002-7017353A patent/KR100498836B1/en not_active IP Right Cessation
- 2001-05-21 EP EP01936596A patent/EP1292532B1/en not_active Expired - Lifetime
- 2001-05-21 CN CNB018113265A patent/CN1212967C/en not_active Expired - Fee Related
- 2001-05-21 AU AU2001262472A patent/AU2001262472A1/en not_active Abandoned
- 2001-05-21 WO PCT/FR2001/001553 patent/WO2001098203A1/en active IP Right Grant
- 2001-05-23 TW TW090112391A patent/TWI234545B/en not_active IP Right Cessation
-
2002
- 2002-11-18 ZA ZA200209366A patent/ZA200209366B/en unknown
- 2002-11-27 NO NO20025703A patent/NO20025703L/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| AU2001262472A1 (en) | 2002-01-02 |
| NO20025703D0 (en) | 2002-11-27 |
| FR2810308A1 (en) | 2001-12-21 |
| CN1436151A (en) | 2003-08-13 |
| EP1292532B1 (en) | 2011-06-22 |
| BR0111783A (en) | 2003-05-27 |
| WO2001098203A1 (en) | 2001-12-27 |
| TWI234545B (en) | 2005-06-21 |
| FR2810308B1 (en) | 2002-07-26 |
| KR20030036235A (en) | 2003-05-09 |
| CN1212967C (en) | 2005-08-03 |
| NO20025703L (en) | 2002-11-27 |
| US20040011663A1 (en) | 2004-01-22 |
| JP4113428B2 (en) | 2008-07-09 |
| EP1292532A1 (en) | 2003-03-19 |
| KR100498836B1 (en) | 2005-07-04 |
| MXPA02012876A (en) | 2003-05-14 |
| JP2003535800A (en) | 2003-12-02 |
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