CN116654889A - Method for preparing ferric phosphate by recycling glyphosate production wastewater - Google Patents
Method for preparing ferric phosphate by recycling glyphosate production wastewater Download PDFInfo
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- CN116654889A CN116654889A CN202310542589.7A CN202310542589A CN116654889A CN 116654889 A CN116654889 A CN 116654889A CN 202310542589 A CN202310542589 A CN 202310542589A CN 116654889 A CN116654889 A CN 116654889A
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- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 title claims abstract description 103
- 239000005955 Ferric phosphate Substances 0.000 title claims abstract description 91
- 229940032958 ferric phosphate Drugs 0.000 title claims abstract description 91
- 229910000399 iron(III) phosphate Inorganic materials 0.000 title claims abstract description 91
- 239000005562 Glyphosate Substances 0.000 title claims abstract description 46
- XDDAORKBJWWYJS-UHFFFAOYSA-N glyphosate Chemical compound OC(=O)CNCP(O)(O)=O XDDAORKBJWWYJS-UHFFFAOYSA-N 0.000 title claims abstract description 46
- 229940097068 glyphosate Drugs 0.000 title claims abstract description 46
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 44
- 239000002351 wastewater Substances 0.000 title claims abstract description 44
- 238000000034 method Methods 0.000 title claims abstract description 37
- 238000004064 recycling Methods 0.000 title claims abstract description 25
- 238000001914 filtration Methods 0.000 claims abstract description 35
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 31
- 239000011574 phosphorus Substances 0.000 claims abstract description 31
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 31
- 230000032683 aging Effects 0.000 claims abstract description 26
- 239000012535 impurity Substances 0.000 claims abstract description 26
- 239000003513 alkali Substances 0.000 claims abstract description 18
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 17
- 238000001035 drying Methods 0.000 claims abstract description 17
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 17
- 239000002253 acid Substances 0.000 claims abstract description 15
- 238000001556 precipitation Methods 0.000 claims abstract description 14
- 238000000498 ball milling Methods 0.000 claims abstract description 11
- 239000007787 solid Substances 0.000 claims abstract description 9
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 7
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 7
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000011575 calcium Substances 0.000 claims abstract description 7
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 7
- 239000011777 magnesium Substances 0.000 claims abstract description 7
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 7
- 230000001502 supplementing effect Effects 0.000 claims abstract description 6
- 230000003213 activating effect Effects 0.000 claims abstract description 3
- 238000002386 leaching Methods 0.000 claims abstract description 3
- 239000002244 precipitate Substances 0.000 claims description 58
- 239000000243 solution Substances 0.000 claims description 35
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 31
- 238000005406 washing Methods 0.000 claims description 24
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 22
- 239000007788 liquid Substances 0.000 claims description 22
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 21
- 239000008367 deionised water Substances 0.000 claims description 18
- 229910021641 deionized water Inorganic materials 0.000 claims description 18
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 16
- 239000000706 filtrate Substances 0.000 claims description 15
- 238000002156 mixing Methods 0.000 claims description 15
- 239000012065 filter cake Substances 0.000 claims description 10
- 229910052742 iron Inorganic materials 0.000 claims description 10
- 229910021578 Iron(III) chloride Inorganic materials 0.000 claims description 8
- 229910000147 aluminium phosphate Inorganic materials 0.000 claims description 8
- 238000004090 dissolution Methods 0.000 claims description 8
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 claims description 8
- 230000008569 process Effects 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 5
- 239000011259 mixed solution Substances 0.000 claims description 3
- 238000002791 soaking Methods 0.000 claims description 3
- 230000004913 activation Effects 0.000 claims description 2
- 238000000926 separation method Methods 0.000 claims description 2
- 230000001376 precipitating effect Effects 0.000 claims 1
- 238000011084 recovery Methods 0.000 abstract description 4
- 238000003756 stirring Methods 0.000 description 17
- 229910000398 iron phosphate Inorganic materials 0.000 description 13
- 238000002360 preparation method Methods 0.000 description 9
- 239000002994 raw material Substances 0.000 description 7
- 239000013078 crystal Substances 0.000 description 6
- 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 description 5
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 239000002002 slurry Substances 0.000 description 5
- 239000011734 sodium Substances 0.000 description 5
- 229910052708 sodium Inorganic materials 0.000 description 5
- DHMQDGOQFOQNFH-UHFFFAOYSA-N Glycine Chemical compound NCC(O)=O DHMQDGOQFOQNFH-UHFFFAOYSA-N 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 230000018109 developmental process Effects 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- 239000004471 Glycine Substances 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 229910019142 PO4 Inorganic materials 0.000 description 2
- 235000011114 ammonium hydroxide Nutrition 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 2
- 239000010452 phosphate Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000002243 precursor Substances 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 239000005696 Diammonium phosphate Substances 0.000 description 1
- 229930040373 Paraformaldehyde Natural products 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 description 1
- 229910000387 ammonium dihydrogen phosphate Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- MNNHAPBLZZVQHP-UHFFFAOYSA-N diammonium hydrogen phosphate Chemical compound [NH4+].[NH4+].OP([O-])([O-])=O MNNHAPBLZZVQHP-UHFFFAOYSA-N 0.000 description 1
- 229910000388 diammonium phosphate Inorganic materials 0.000 description 1
- 235000019838 diammonium phosphate Nutrition 0.000 description 1
- -1 dihydrate ferric phosphate Chemical class 0.000 description 1
- CZHYKKAKFWLGJO-UHFFFAOYSA-N dimethyl phosphite Chemical compound COP([O-])OC CZHYKKAKFWLGJO-UHFFFAOYSA-N 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000032050 esterification Effects 0.000 description 1
- 238000005886 esterification reaction Methods 0.000 description 1
- 229960004887 ferric hydroxide Drugs 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 230000002363 herbicidal effect Effects 0.000 description 1
- 239000004009 herbicide Substances 0.000 description 1
- IEECXTSVVFWGSE-UHFFFAOYSA-M iron(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Fe+3] IEECXTSVVFWGSE-UHFFFAOYSA-M 0.000 description 1
- BMTOKWDUYJKSCN-UHFFFAOYSA-K iron(3+);phosphate;dihydrate Chemical compound O.O.[Fe+3].[O-]P([O-])([O-])=O BMTOKWDUYJKSCN-UHFFFAOYSA-K 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000002503 metabolic effect Effects 0.000 description 1
- CAAULPUQFIIOTL-UHFFFAOYSA-N methyl dihydrogen phosphate Chemical compound COP(O)(O)=O CAAULPUQFIIOTL-UHFFFAOYSA-N 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 235000019837 monoammonium phosphate Nutrition 0.000 description 1
- 239000006012 monoammonium phosphate Substances 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- 239000007773 negative electrode material Substances 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 239000003987 organophosphate pesticide Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229920002866 paraformaldehyde Polymers 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- AWRQDLAZGAQUNZ-UHFFFAOYSA-K sodium;iron(2+);phosphate Chemical compound [Na+].[Fe+2].[O-]P([O-])([O-])=O AWRQDLAZGAQUNZ-UHFFFAOYSA-K 0.000 description 1
- 238000000967 suction filtration Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 230000009466 transformation Effects 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
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/37—Phosphates of heavy metals
- C01B25/375—Phosphates of heavy metals of iron
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides a method for preparing ferric phosphate by recycling glyphosate production wastewater, which comprises the following steps: s1, precipitation; s2, roasting; s3, ball milling and activating; s4, acid leaching; s5, adding alkali to adjust the pH; s6, supplementing phosphorus and aging; s7, removing impurities by nitric acid: transferring the obtained ferric phosphate dihydrate into a dilute nitric acid solution for impurity removal, and removing calcium, magnesium and aluminum in the ferric phosphate dihydrate; s8, secondary roasting: and (3) filtering the solution in the step (S7), drying the washed solid matters, and roasting the dried solid matters in a furnace again to obtain the ferric phosphate. The invention realizes the double recovery of organic phosphorus and inorganic phosphorus, realizes the recovery and utilization of the waste water in the production of glyphosate, and converts the waste water into high-purity battery-grade ferric phosphate.
Description
Technical Field
The invention relates to the technical field of ferric phosphate, in particular to a production process for preparing ferric phosphate by taking glyphosate production wastewater as a raw material. Meanwhile, the invention also belongs to the technical field of waste liquid recycling in glyphosate production.
Background
In recent years, with the rapid development of new energy industries and the increasing improvement of life quality of people, new energy automobiles have come into the public view, and the demands of people for new energy automobiles are increasing. With the rapid development of new energy automobiles and energy storage power stations, the lithium iron phosphate battery which has the characteristics of no noble metal, low price, abundant resources, stable structure, safety, reliability, long charging life and environmental protection and no toxicity is greatly applied. Since iron phosphate is found to be a precursor for preparing lithium iron phosphate, the iron phosphate has received high attention from domestic and foreign scientists, can be used as a precursor for synthesizing lithium iron phosphate, can be directly used as a positive electrode material of a lithium battery, can also be used as a negative electrode material of the lithium battery, and has a rapid increase in demand, and a preparation method thereof is a hot spot of current research.
The existing ferric phosphate takes battery grade or industrial grade monoammonium phosphate, diammonium phosphate or purified phosphoric acid as a phosphorus source, and divalent or trivalent ferric salt as an iron source, and the battery grade ferric phosphate is prepared by a chemical reaction mode. Chinese patent 200810026602.9 discloses a high-density spherical ferric phosphate and a preparation method thereof, wherein an iron source and an additive are used as raw materials, phosphate is used as a phosphorus source, and the high-density spherical ferric phosphate with dispersed particles and uniform size is obtained. The existing phosphorus source generally has the problems of high cost, shortage of phosphorus source and the like, seriously reduces the advantages of lithium iron phosphate, even can directly influence the development of the lithium iron phosphate industry, and the phosphorus source material for preparing the iron phosphate material needs to be continuously developed.
Glyphosate is one of the most mainstream herbicides, and has the chemical name of N- (methyl phosphate) glycine, and is a broad-spectrum organophosphorus pesticide with higher herbicidal activity. The production process generally adopts an alkyl esterification process which takes glycine, paraformaldehyde and dimethyl phosphite as raw materials. Wherein, during the synthesis of glyphosate, a large amount of phosphorus-containing mother liquor (about 1.5 percent of glyphosate, glyphosate and metabolic products thereof and other organic phosphorus) is generated, the salinity is about 15 percent, the Chemical Oxygen Demand (COD) is more than 20000, and the method has the characteristics of complex components, difficult degradation, high treatment difficulty and the like, and the sewage treatment cost is high. If the waste water from the production of glyphosate is used as the raw material for preparing ferric phosphate, the range of the phosphorus source can be enlarged, the utilization rate of the phosphorus resource can be improved, and considerable social benefit and economic benefit can be brought. However, the content of soluble impurities in the waste water of the glyphosate production is higher than that of phosphate, and the product quality cannot meet the standard when the waste water is directly used for producing ferric phosphate, so that a method for preparing ferric phosphate meeting the standard by recycling the waste water of the glyphosate production is necessary to be developed.
Chinese patent application CN 115321736A discloses a method for treating waste water from glyphosate production and high-value reuse of phosphorus-containing waste, and discloses mixing waste water from glyphosate production with iron source to obtain ferrophosphorus complex precipitation solution. On the basis of the method, the invention focuses on the refining impurity removal of crude ferric phosphate, and removes sodium, calcium, magnesium, aluminum and other impurities in the crude ferric phosphate to obtain the high-purity battery-grade ferric phosphate.
Disclosure of Invention
The invention aims to solve the technical problem of providing the method for preparing the ferric phosphate by recycling the waste water of the glyphosate production, which effectively utilizes the phosphorus element in the waste water of the glyphosate production, provides a brand-new raw material source for the preparation of the ferric phosphate, improves the utilization rate and economic benefit of phosphorus resources, and has high purity of the prepared ferric phosphate and environmental friendliness.
In order to solve the technical problems, the invention provides a method for preparing ferric phosphate by recycling waste water from glyphosate production, which comprises the following steps:
(1) Precipitation: mixing the glyphosate production wastewater with ferric chloride, adding hydrochloric acid under a stirring state, and controlling the pH value of the mixed solution to be 2-3, preferably 2.5 to obtain a complex precipitation solution of phosphorus and iron;
(2) Roasting: carrying out solid-liquid separation on the complex precipitation solution of phosphorus and iron in the step (1), and placing the separated solid matters into a calcination rotary kiln, and roasting for 4-8 hours in an air atmosphere at a roasting temperature of 400-600 ℃ to obtain crude ferric phosphate;
(3) Ball milling and activating: placing the crude ferric phosphate obtained in the step (2) into a planetary ball mill for ball milling activation, wherein the ball milling time is 0.5-2 hours;
(4) Acid leaching: adding the solid powder obtained in the step (3) into hydrochloric acid, controlling the solid-liquid ratio to be between 1:10 and 1:20, mixing the solid powder and the hydrochloric acid, and then putting the mixture into an instant magnetic stirrer for heating and dissolving, wherein the stirring speed is 500rpm, the heating temperature is 60-80 ℃, and the acid dissolving time is 4-8 hours; filtering after dissolution is completed;
(5) Adding alkali to adjust pH: adding alkali liquor into the filtrate obtained in the step (4) to adjust the pH value to 1.5-2.5, such as 1.5, 2.0 or 2.5, controlling the temperature of the filtrate to be 60-105 ℃ when the alkali liquor is added, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate, washing the precipitate with deionized water, and removing sodium impurities;
(6) Supplementing phosphorus and aging: mixing the precipitate obtained in the step (5) with water in proportion, adding dilute acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, filtering after aging to obtain a light pink filter cake, washing and drying to obtain ferric phosphate dihydrate;
(7) Removing impurities by nitric acid: transferring the obtained ferric phosphate dihydrate into a dilute nitric acid solution for impurity removal, removing impurities such as calcium, magnesium, aluminum and the like in the ferric phosphate dihydrate, and filtering to obtain high-purity ferric phosphate dihydrate;
(8) And (3) secondary roasting: roasting the dihydrate ferric phosphate in a muffle furnace at 600-800 ℃ for 2-4 h under the air atmosphere to obtain the high-purity ferric phosphate.
According to the invention, after ferric chloride is added, the pH value of the mixed solution is ensured to be about 2.5, and the complexing of both organic phosphorus and inorganic phosphorus in the glyphosate production wastewater with an iron source can be realized at the same time, so that the recycling of phosphorus is effectively realized, and the recovery rate is high.
In the invention, the pH value of the glyphosate production wastewater is 9.14, and the total phosphorus content is 12269ppm.
In the invention, in the step (2), before roasting, the ferrophosphorus complex precipitate is washed and dried, deionized water is adopted for washing for 3 times, and then the precipitate is dried for 8 hours at the normal pressure at the temperature of 105 ℃ to remove free water.
In the invention, the concentration of hydrochloric acid used in the step (4) is 5mol/L to 12mol/L.
In the invention, undissolved sediment in the step (4) can enter the step (1) again for circulation.
In the present invention, the alkali liquor mentioned in the step (5) is a sodium hydroxide solution, and the concentration thereof is 6mol/L to 14mol/L.
In the invention, the filtering process in the step (5) comprises the steps of carrying out suction filtration on the precipitation solution, and then washing the filter cake for 1-3 times by deionized water with the mass of 3-5 times of the filter cake.
In the invention, the dilute acid in the step (6) is phosphoric acid, the aging temperature is 50-100 ℃, and the aging time is 3-6 hours; the washing times are 2-4 times.
In the invention, the concentration of the dilute nitric acid in the step (7) is 2% -10%, and the solid-liquid ratio is 1: 2-1: 10, soaking the ferric phosphate dihydrate containing impurities in the nitric acid solution for 0.5-12 h in the impurity removing process.
The method for preparing the ferric phosphate by recycling the glyphosate production wastewater has the following beneficial effects:
1. according to the preparation method disclosed by the invention, the glyphosate production wastewater is used as a phosphorus source, so that organic phosphorus and inorganic phosphorus in the wastewater are effectively utilized, the source of raw materials for preparing the ferric phosphate is enriched, and the cost of the raw materials for preparing the ferric phosphate is reduced; effectively recycling the waste water of the glyphosate production and reducing the environmental pollution caused by the waste water of the glyphosate production;
2. the method adopts the sodium precipitation to prepare the ferric phosphate, so that the defects of high ammonia water recovery cost, environmental protection and the like caused by the preparation of the ferric phosphate by the traditional ammonia water precipitation method can be effectively avoided, and meanwhile, the influence of the ferric hydroxide generated by partial overbase during the sodium precipitation on a final product is effectively avoided by adopting phosphoric acid aging; the water washing procedure is added between the precipitation reaction and the aging reaction, so that the impurity elements can be obviously prevented from being embedded into crystal lattices in the crystal form transformation process of the aging reaction.
3. According to the invention, the crystal is grown by adopting phosphorus supplementing and aging, and the obtained ferric phosphate has good crystallinity; the impurities such as calcium, magnesium, aluminum and the like which are easy to precipitate simultaneously in the iron phosphate dihydrate are removed by soaking in the nitric acid solution, the purity of the prepared iron phosphate is high and can reach more than 99.5%, and the Fe: P atomic ratio of the prepared iron phosphate product is between 0.968 and 0.993, so that the prepared iron phosphate meets the requirements of battery grade iron phosphate.
Drawings
Fig. 1 is a process flow diagram for preparing iron phosphate by recycling glyphosate production wastewater provided in example 1.
Fig. 2 is an XRD pattern of iron phosphate prepared in example 2.
FIG. 3 is a scanning electron microscope image of the iron phosphate prepared in example 2.
Detailed Description
The technical scheme of the invention is described in detail below with reference to the accompanying drawings and examples.
Comparative example 1
A method for preparing ferric phosphate by recycling glyphosate production wastewater comprises the following steps:
(1) Adding ferric chloride into 2000mL of glyphosate production wastewater, adding hydrochloric acid, stirring for 10min, standing for 30min, wherein the pH value of the solution is 2.5, and performing centrifugal filtration on the milky slurry solution to obtain a white precipitated ferrophosphorus complex;
(2) Washing the precipitate with deionized water for 3 times, and drying in an oven at 105 ℃ under normal pressure for 8 hours to remove free water. Placing the dried precipitate into a rotary kiln, and roasting for 8 hours at 400 ℃ in an air atmosphere to obtain crude ferric phosphate;
(3) Adding the crude ferric phosphate into 5mol/L hydrochloric acid, wherein the solid-liquid ratio is 1:10, mixing and then placing the mixture into an instant magnetic stirrer, wherein the temperature is 60 ℃, the stirring speed is 500rpm, the acid dissolution time is 8 hours, and filtering is carried out after the sample is dissolved;
(4) Adding 6mol/L sodium hydroxide solution into the filtrate obtained in the step (3) to adjust the pH value to 1.5, adding alkali liquor while stirring, controlling the temperature at 60 ℃ when adding alkali to adjust the pH value, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate and washing the precipitate with deionized water for 3 times;
(5) And (3) drying the precipitate, and roasting the precipitate in a muffle furnace at 600 ℃ for 4 hours in an air atmosphere to obtain the ferric phosphate.
Example 1
As shown in figure 1, the method for preparing the ferric phosphate by recycling the glyphosate production wastewater comprises the following steps:
(1) Adding ferric chloride into 2000mL of glyphosate production wastewater, adding hydrochloric acid, stirring for 10min, standing for 30min, wherein the pH value of the solution is 2.5, and performing centrifugal filtration on the milky slurry solution to obtain a white precipitated ferrophosphorus complex;
(2) Washing the precipitate with deionized water for 3 times, and drying in an oven at 105 ℃ under normal pressure for 8 hours to remove free water. Placing the dried precipitate into a rotary kiln, and roasting for 8 hours at 400 ℃ in an air atmosphere to obtain crude ferric phosphate;
(3) Placing the crude ferric phosphate obtained in the step (2) into a planetary ball mill, and ball milling for 2 hours;
(4) Adding the crude ferric phosphate into 5mol/L hydrochloric acid, wherein the solid-liquid ratio is 1:10, mixing and then placing the mixture into an instant magnetic stirrer, wherein the temperature is 60 ℃, the stirring speed is 500rpm, the acid dissolution time is 8 hours, and filtering is carried out after the sample is dissolved;
(5) Adding 6mol/L sodium hydroxide solution into the filtrate obtained in the step (4) to adjust the pH value to 1.5, adding alkali liquor while stirring, controlling the temperature at 60 ℃ when the alkali is added to adjust the pH value, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate and washing the precipitate with deionized water for 3 times;
(6) Mixing the precipitate obtained in the step 5 with water according to a solid-to-liquid ratio of 1:10, adding 1.5mol/L phosphoric acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, aging for 4 hours at 90 ℃, filtering to obtain a light pink filter cake, washing with deionized water for 2 times, and drying at 80 ℃ for 8 hours to obtain ferric phosphate dihydrate;
(7) And (3) baking the precipitate for 4 hours in an air atmosphere at 600 ℃ in a muffle furnace to obtain ferric phosphate, wherein an XRD (X-ray diffraction) pattern and a Scanning Electron Microscope (SEM) pattern of the ferric phosphate are shown in fig. 2 and 3 respectively, and the ferric phosphate obtained in the embodiment can be seen from fig. 2 and 3.
Example 2
A method for preparing ferric phosphate by recycling glyphosate production wastewater comprises the following steps:
(1) Adding ferric chloride into 2000mL of glyphosate production wastewater, adding hydrochloric acid, stirring for 10min, standing for 30min, wherein the pH value of the solution is 2.5, and performing centrifugal filtration on the milky slurry solution to obtain a white precipitated ferrophosphorus complex;
(2) Washing the precipitate with deionized water for 3 times, and drying in an oven at 105 ℃ under normal pressure for 8 hours to remove free water. Placing the dried precipitate into a rotary kiln, and roasting for 8 hours at 400 ℃ in an air atmosphere to obtain crude ferric phosphate;
(3) Placing the crude ferric phosphate obtained in the step (2) into a planetary ball mill, and ball milling for 2 hours;
(4) Adding the crude ferric phosphate into 5mol/L hydrochloric acid, wherein the solid-liquid ratio is 1:10, mixing and then placing the mixture into an instant magnetic stirrer, wherein the temperature is 60 ℃, the stirring speed is 500rpm, the acid dissolution time is 8 hours, and filtering is carried out after the sample is dissolved;
(5) Adding 6mol/L sodium hydroxide solution into the filtrate obtained in the step (4) to adjust the pH value to 1.5, adding alkali liquor while stirring, controlling the temperature at 60 ℃ when the alkali is added to adjust the pH value, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate and washing the precipitate with deionized water for 3 times;
(6) Mixing the precipitate obtained in the step 5 with water according to a solid-to-liquid ratio of 1:10, adding 1.5mol/L phosphoric acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, aging for 4 hours at 90 ℃, filtering to obtain a light pink filter cake, washing with deionized water for 2 times, and drying at 80 ℃ for 8 hours to obtain ferric phosphate dihydrate;
(7) Transferring the obtained ferric phosphate dihydrate into 2% dilute nitric acid solution for impurity removal, wherein the solid-to-liquid ratio is 1:5, filtering to obtain high-purity ferric phosphate dihydrate;
(8) And (3) drying the precipitate, and roasting the precipitate in a muffle furnace at 600 ℃ for 4 hours in an air atmosphere to obtain the ferric phosphate.
Example 3
A method for preparing ferric phosphate by recycling glyphosate production wastewater comprises the following steps:
(1) Adding ferric chloride into 2000mL of glyphosate production wastewater, adding hydrochloric acid, stirring for 10min, standing for 30min, wherein the pH value of the solution is 2.5, and performing centrifugal filtration on the milky slurry solution to obtain a white precipitated ferrophosphorus complex;
(2) Washing the precipitate with deionized water for 3 times, and drying in an oven at 105 ℃ under normal pressure for 8 hours to remove free water. Placing the dried precipitate into a rotary kiln, and roasting for 8 hours at 400 ℃ in an air atmosphere to obtain crude ferric phosphate;
(3) Placing the crude ferric phosphate obtained in the step (2) into a planetary ball mill, and ball milling for 2 hours;
(4) Adding the crude ferric phosphate into 5mol/L hydrochloric acid, wherein the solid-liquid ratio is 1:15, mixing and then placing the mixture into an instant magnetic stirrer, wherein the temperature is 60 ℃, the stirring speed is 500rpm, the acid dissolution time is 6 hours, and filtering is carried out after the sample is dissolved;
(5) Adding 8mol/L sodium hydroxide solution into the filtrate obtained in the step (4) to adjust the pH value to 1.5, adding alkali liquor while stirring, controlling the temperature at 60 ℃ when the alkali is added to adjust the pH value, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate and washing the precipitate with deionized water for 3 times;
(6) Mixing the precipitate obtained in the step 5 with water according to a solid-to-liquid ratio of 1:10, adding 1.5mol/L phosphoric acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, aging for 4 hours at 90 ℃, filtering to obtain a light pink filter cake, washing with deionized water for 2 times, and drying at 80 ℃ for 8 hours to obtain ferric phosphate dihydrate;
(7) Transferring the obtained ferric phosphate dihydrate into 2% dilute nitric acid solution for impurity removal, wherein the solid-to-liquid ratio is 1:5, filtering to obtain high-purity ferric phosphate dihydrate;
(8) And (3) drying the precipitate, and roasting the precipitate in a muffle furnace at 600 ℃ for 4 hours in an air atmosphere to obtain the ferric phosphate.
Example 4
A method for preparing ferric phosphate by recycling glyphosate production wastewater comprises the following steps:
(1) Adding ferric chloride into 2000mL of glyphosate production wastewater, adding hydrochloric acid, stirring for 10min, standing for 30min, wherein the pH value of the solution is 2.5, and performing centrifugal filtration on the milky slurry solution to obtain a white precipitated ferrophosphorus complex;
(2) Washing the precipitate with deionized water for 3 times, and drying in an oven at 105 ℃ under normal pressure for 8 hours to remove free water. Placing the dried precipitate into a rotary kiln, and roasting for 8 hours at 400 ℃ in an air atmosphere to obtain crude ferric phosphate;
(3) Placing the crude ferric phosphate obtained in the step (2) into a planetary ball mill, and ball milling for 2 hours;
(4) Adding the crude ferric phosphate into 5mol/L hydrochloric acid, wherein the solid-liquid ratio is 1:12.5, mixing, putting into an instant magnetic stirrer, stirring at 80 ℃ and 500rpm for 8 hours, and filtering after the sample is dissolved;
(5) Adding 8mol/L sodium hydroxide solution into the filtrate obtained in the step (4) to adjust the pH value to 1.5, adding alkali liquor while stirring, controlling the temperature at 80 ℃ when the alkali is added to adjust the pH value, gradually generating light yellow flocculent precipitate in the filtrate, filtering the precipitate and washing the precipitate with deionized water for 3 times;
(6) Mixing the precipitate obtained in the step 5 with water according to a solid-to-liquid ratio of 1:10, adding 2.0mol/L phosphoric acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, aging for 4 hours at 95 ℃, filtering to obtain a light pink filter cake, washing with deionized water for 2 times, and drying at 80 ℃ for 8 hours to obtain ferric phosphate dihydrate;
(7) Transferring the obtained ferric phosphate dihydrate into 2% dilute nitric acid solution for impurity removal, wherein the solid-to-liquid ratio is 1:5, filtering to obtain high-purity ferric phosphate dihydrate;
(8) And (3) drying the precipitate, and roasting the precipitate in a muffle furnace at 600 ℃ for 4 hours in an air atmosphere to obtain the ferric phosphate.
Example 5
The difference between this example and example 2 is that the solid-to-liquid ratio in step (4) of this example is 1:20 and the acid dissolution time is 4 hours. The remaining preparation methods and parameters were consistent with example 2.
Example 6
The difference between this example and example 2 is that the pH in step (5) of this example was 2.5. The remaining preparation methods and parameters were consistent with example 2.
Example 7
The difference between this example and example 2 is that the baking temperature in step (8) of this example was 800℃and the baking time was 2 hours. The remaining preparation methods and parameters were consistent with example 2.
The iron phosphate components and Fe: P atomic ratios obtained by the preparation methods provided in comparative example 1 and examples 1 to 7, respectively, were measured, and the results are shown in Table 1.
TABLE 1
As can be seen from comparative example 1, the impurity contents of sodium, calcium, magnesium and aluminum in the prepared iron phosphate sample do not meet the requirement of battery grade iron phosphate without the processes of phosphorus supplementing, aging and crystal growing and nitric acid impurity removing, and the embodiment 1 performs the aging and crystal growing on the basis of comparative example 1, so that the content of the obtained iron sodium phosphate is reduced, the national standard requirement is met, and the improvement of crystallinity is proved to be helpful for reducing the impurity content; example 2 was further subjected to nitric acid impurity removal based on example 1, with reduced levels of calcium, magnesium, and aluminum impurities. FePO 4 XRD (prepared in example 2) showed that the sample was substantially identical to that of the standard card (PDF # 01-071-3497), and the diffraction peak was high, the peak width was narrow, indicating that the sample was complete in crystal structure and high in crystallinity, as shown in FIG. 2. FIG. 3 is FePO 4 The scanning electron microscope (prepared in example 2) is in a sphere-like shape, each sphere-like particle is formed by stacking a plurality of smaller irregular granular particles, and the grain size is relatively uniform, so that the method is beneficial to subsequent processing.
The method can be realized by the upper and lower limit values of the interval and the interval value of the process parameters (such as temperature, time and the like), and the examples are not necessarily listed here.
The invention may be practiced without these specific details, using any knowledge known in the art.
Finally, it should be noted that the above embodiments are only for illustrating the technical solution of the present invention and are not limiting. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the present invention, which is intended to be covered by the appended claims.
Claims (9)
1. A method for preparing ferric phosphate by recycling glyphosate production wastewater, which comprises the following steps:
s1 precipitation: mixing the glyphosate production wastewater with an iron source, and controlling the pH value of the mixed solution to be 2-3 to obtain a complex precipitation solution of phosphorus and iron;
s2, roasting: carrying out solid-liquid separation on the complex precipitation solution of phosphorus and iron obtained in the step S1 to obtain separated liquid substances and solid substances, and roasting the separated solid substances to obtain crude ferric phosphate;
s3, ball milling and activating: placing the crude ferric phosphate obtained in the step S2 into a planetary ball mill for ball milling activation, wherein the ball milling time is 0.5-2 hours;
s4 acid leaching: adding the ball-milled crude ferric phosphate of the step S3 into hydrochloric acid according to a certain solid-to-liquid ratio, putting the hydrochloric acid into an instant magnetic stirrer for dissolving a sample, and then filtering;
s5, adding alkali to adjust pH: adding alkali liquor into the filtrate obtained after filtering in the step S4 to adjust the pH value, filtering and precipitating until light yellow flocculent precipitate appears in the filtrate, and washing;
s6, supplementing phosphorus and aging: mixing the precipitate obtained in the step S5 with water in proportion, adding dilute acid, aging after the yellow flocculent precipitate is converted into white flocculent precipitate, filtering after aging to obtain a light pink filter cake, washing and drying to obtain ferric phosphate dihydrate;
s7, removing impurities by nitric acid: transferring the obtained ferric phosphate dihydrate into a dilute nitric acid solution for impurity removal, and removing calcium, magnesium and aluminum in the ferric phosphate dihydrate;
s8, secondary roasting: and (3) filtering the solution in the step (S7), drying the washed solid matters, and roasting the dried solid matters in a furnace again to obtain the ferric phosphate.
2. The method for preparing ferric phosphate by recycling glyphosate production wastewater according to claim 1, wherein the iron source in S1 is ferric chloride.
3. The method for preparing ferric phosphate by recycling waste water in glyphosate production according to claim 1, wherein the roasting temperature of S2 is 400-600 ℃, the roasting atmosphere is air atmosphere, the roasting time is 4-8 h, and the equipment used for roasting is a roasting rotary kiln.
4. The method for preparing ferric phosphate by recycling the glyphosate production wastewater according to claim 1, wherein the solid-to-liquid ratio of S4 is 1:10-1: 20, the concentration of hydrochloric acid is 5mol/L to 12mol/L, the acid dissolution temperature is 60 ℃ to 80 ℃ and the acid dissolution time is 4 to 8 hours.
5. The method for preparing ferric phosphate by recycling waste water in glyphosate production according to claim 1, wherein the alkali solution in S5 is sodium hydroxide solution with the concentration of 6 mol/L-14 mol/L and the pH value is adjusted to be 1.5-2.5.
6. The method for preparing ferric phosphate by recycling waste water in glyphosate production according to claim 1, wherein the filtering in S6 comprises suction filtering the precipitation solution, and then washing the filter cake with deionized water 3-5 times the mass of the filter cake for 2-4 times.
7. The method for preparing ferric phosphate by recycling the waste water generated in the production of glyphosate according to claim 1, wherein in the S6 phosphorus supplementing and aging process, the dilute acid is phosphoric acid, the aging temperature is 50-100 ℃, and the aging time is 3-6 hours; the washing times are 2-4 times.
8. The method for preparing ferric phosphate by recycling the glyphosate production wastewater according to claim 1, wherein in the S7 nitric acid impurity removal, the concentration of the dilute nitric acid is 2% -10%, and the solid-to-liquid ratio is 1: 2-1: 10, soaking the ferric phosphate dihydrate containing impurities in the nitric acid solution for 0.5-12 h in the impurity removing process.
9. The method for preparing ferric phosphate by recycling waste water in glyphosate production according to claim 1, wherein the secondary roasting temperature of S8 is 600-800 ℃, the roasting atmosphere is air atmosphere, and the roasting time is 2-4 h.
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