CN117550575A - Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite - Google Patents
Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite Download PDFInfo
- Publication number
- CN117550575A CN117550575A CN202311745620.3A CN202311745620A CN117550575A CN 117550575 A CN117550575 A CN 117550575A CN 202311745620 A CN202311745620 A CN 202311745620A CN 117550575 A CN117550575 A CN 117550575A
- Authority
- CN
- China
- Prior art keywords
- solution
- phosphate
- phosphorite
- crude acid
- ferric phosphate
- 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.)
- Pending
Links
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 title claims abstract description 87
- 239000005955 Ferric phosphate Substances 0.000 title claims abstract description 76
- 229940032958 ferric phosphate Drugs 0.000 title claims abstract description 76
- 229910000399 iron(III) phosphate Inorganic materials 0.000 title claims abstract description 76
- 239000002253 acid Substances 0.000 title claims abstract description 68
- 239000002367 phosphate rock Substances 0.000 title claims abstract description 62
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical compound OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 44
- 239000000243 solution Substances 0.000 claims abstract description 83
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims abstract description 53
- 239000010452 phosphate Substances 0.000 claims abstract description 53
- 229910019142 PO4 Inorganic materials 0.000 claims abstract description 52
- 239000011790 ferrous sulphate Substances 0.000 claims abstract description 40
- 235000003891 ferrous sulphate Nutrition 0.000 claims abstract description 40
- 229910000359 iron(II) sulfate Inorganic materials 0.000 claims abstract description 40
- 239000007788 liquid Substances 0.000 claims abstract description 33
- 238000005406 washing Methods 0.000 claims abstract description 33
- 238000000926 separation method Methods 0.000 claims abstract description 26
- 239000011259 mixed solution Substances 0.000 claims abstract description 25
- 239000011268 mixed slurry Substances 0.000 claims abstract description 21
- 239000012065 filter cake Substances 0.000 claims abstract description 20
- 239000007800 oxidant agent Substances 0.000 claims abstract description 20
- 230000032683 aging Effects 0.000 claims abstract description 19
- 238000001354 calcination Methods 0.000 claims abstract description 19
- 238000003756 stirring Methods 0.000 claims abstract description 19
- 239000007864 aqueous solution Substances 0.000 claims abstract description 18
- 230000001590 oxidative effect Effects 0.000 claims abstract description 18
- 238000001035 drying Methods 0.000 claims abstract description 16
- 238000010438 heat treatment Methods 0.000 claims abstract description 15
- 230000001105 regulatory effect Effects 0.000 claims abstract description 11
- 238000002156 mixing Methods 0.000 claims abstract description 8
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims abstract 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 17
- 239000002002 slurry Substances 0.000 claims description 17
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 14
- 239000011574 phosphorus Substances 0.000 claims description 14
- 229910052698 phosphorus Inorganic materials 0.000 claims description 14
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 13
- 239000001099 ammonium carbonate Substances 0.000 claims description 13
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical group OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 12
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 12
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 12
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 11
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 11
- 229910000013 Ammonium bicarbonate Inorganic materials 0.000 claims description 7
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 claims description 7
- 235000012538 ammonium bicarbonate Nutrition 0.000 claims description 7
- 239000011736 potassium bicarbonate Substances 0.000 claims description 7
- 235000015497 potassium bicarbonate Nutrition 0.000 claims description 7
- 229910000028 potassium bicarbonate Inorganic materials 0.000 claims description 7
- TYJJADVDDVDEDZ-UHFFFAOYSA-M potassium hydrogencarbonate Chemical compound [K+].OC([O-])=O TYJJADVDDVDEDZ-UHFFFAOYSA-M 0.000 claims description 7
- 235000012501 ammonium carbonate Nutrition 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 6
- 239000003002 pH adjusting agent Substances 0.000 claims description 6
- 229910000027 potassium carbonate Inorganic materials 0.000 claims description 6
- 235000011181 potassium carbonates Nutrition 0.000 claims description 6
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 6
- 235000017550 sodium carbonate Nutrition 0.000 claims description 6
- 239000003513 alkali Substances 0.000 claims description 4
- 239000002585 base Substances 0.000 claims description 4
- PFUVRDFDKPNGAV-UHFFFAOYSA-N sodium peroxide Chemical compound [Na+].[Na+].[O-][O-] PFUVRDFDKPNGAV-UHFFFAOYSA-N 0.000 claims description 4
- 238000004321 preservation Methods 0.000 claims description 2
- 239000002686 phosphate fertilizer Substances 0.000 abstract description 6
- 239000002910 solid waste Substances 0.000 abstract description 4
- 239000012535 impurity Substances 0.000 description 37
- SURQXAFEQWPFPV-UHFFFAOYSA-L iron(2+) sulfate heptahydrate Chemical compound O.O.O.O.O.O.O.[Fe+2].[O-]S([O-])(=O)=O SURQXAFEQWPFPV-UHFFFAOYSA-L 0.000 description 37
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 20
- 238000006243 chemical reaction Methods 0.000 description 19
- 239000000047 product Substances 0.000 description 17
- 239000002245 particle Substances 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 13
- 239000013078 crystal Substances 0.000 description 12
- 229910000398 iron phosphate Inorganic materials 0.000 description 11
- 238000003786 synthesis reaction Methods 0.000 description 11
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 10
- 238000001514 detection method Methods 0.000 description 9
- 230000015572 biosynthetic process Effects 0.000 description 8
- 230000001276 controlling effect Effects 0.000 description 8
- 238000001914 filtration Methods 0.000 description 7
- 238000002360 preparation method Methods 0.000 description 7
- 239000000203 mixture Substances 0.000 description 6
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 5
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- 239000012266 salt solution Substances 0.000 description 5
- 238000001878 scanning electron micrograph Methods 0.000 description 5
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 4
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 4
- 238000010009 beating Methods 0.000 description 4
- 229910001416 lithium ion Inorganic materials 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000006227 byproduct Substances 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 239000012452 mother liquor Substances 0.000 description 3
- 230000006911 nucleation Effects 0.000 description 3
- 238000010899 nucleation Methods 0.000 description 3
- 238000001556 precipitation Methods 0.000 description 3
- 238000004537 pulping Methods 0.000 description 3
- 235000010215 titanium dioxide Nutrition 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- LFVGISIMTYGQHF-UHFFFAOYSA-N ammonium dihydrogen phosphate Chemical compound [NH4+].OP(O)([O-])=O LFVGISIMTYGQHF-UHFFFAOYSA-N 0.000 description 2
- 229910000387 ammonium dihydrogen phosphate Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 229960004887 ferric hydroxide Drugs 0.000 description 2
- -1 iron furan phosphate Chemical compound 0.000 description 2
- IEECXTSVVFWGSE-UHFFFAOYSA-M iron(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Fe+3] IEECXTSVVFWGSE-UHFFFAOYSA-M 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- 235000019837 monoammonium phosphate Nutrition 0.000 description 2
- 239000006012 monoammonium phosphate Substances 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 230000001376 precipitating effect Effects 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 239000004408 titanium dioxide Substances 0.000 description 2
- 229910017119 AlPO Inorganic materials 0.000 description 1
- 239000005696 Diammonium phosphate Substances 0.000 description 1
- 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 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 238000007259 addition reaction Methods 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 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
- 238000007865 diluting Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- YWEUIGNSBFLMFL-UHFFFAOYSA-N diphosphonate Chemical compound O=P(=O)OP(=O)=O YWEUIGNSBFLMFL-UHFFFAOYSA-N 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000000921 elemental analysis Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 229940116007 ferrous phosphate Drugs 0.000 description 1
- 230000002431 foraging effect Effects 0.000 description 1
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical class [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000155 iron(II) phosphate Inorganic materials 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000010413 mother solution Substances 0.000 description 1
- 150000003017 phosphorus Chemical class 0.000 description 1
- DLYUQMMRRRQYAE-UHFFFAOYSA-N phosphorus pentoxide Inorganic materials O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 235000015424 sodium Nutrition 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 239000002351 wastewater Substances 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
- C01P2004/61—Micrometer sized, i.e. from 1-100 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
- C01P2006/40—Electric properties
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Iron (AREA)
Abstract
The invention provides a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite, which belongs to the technical field of batteries and comprises the following steps: providing an aqueous solution of crude acid of phosphorite and a ferrous sulfate solution; regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution; mixing the phosphate solution with an oxidant to obtain a mixed solution; dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake; and sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate. The invention has the following advantages: (1) the crude acid price of phosphorite is low; (2) the process is simple, the filter residue can be used as phosphate fertilizer for sale treatment, and solid waste is not worried about; (3) the specific surface area of the anhydrous ferric phosphate can be increased.
Description
Technical Field
The invention belongs to the technical field of batteries, and particularly relates to a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite.
Background
Iron phosphate is a multipurpose compound, which can exist in various forms, such as iron phosphate, iron furan phosphate and the like, and battery grade iron phosphate is a novel lithium ion battery material and belongs to a phosphate positive electrode material.
Compared with the traditional lithium ion battery, the battery-level ferric phosphate has a plurality of excellent characteristics, so that the battery-level ferric phosphate occupies important positions in the battery production and battery charging fields, the battery-level ferric phosphate can effectively prevent the corrosion inside the battery, effectively prolong the service life of the battery, and maintain the optimal running performance of the battery; the lithium ion battery has excellent electrochemical activity, can be used for manufacturing lithium ion batteries and lead-acid batteries, can realize quick charge, has good recycling performance, and is widely applied to the field of electric automobiles.
The existing preparation method of the ferric phosphate adopts the procedures of preparing ferrous sulfate heptahydrate as a titanium dioxide byproduct, preparing an iron source through procedures of dissolving pure water, adjusting pH, and the like, preparing a phosphate solution required by synthesizing the ferric phosphate as a phosphorus source through procedures of dissolving industrial-grade monoammonium phosphate, diammonium phosphate or purified phosphoric acid by pure water, adjusting pH, and the like, and preparing the battery-grade ferric phosphate through a chemical reaction mode, wherein the process has higher raw material cost, and the overall production cost of the ferric phosphate is extremely high. Therefore, there is a need to develop a new process study for producing battery grade iron phosphate from raw materials at low cost.
Disclosure of Invention
In view of the technical problems in the background art, the invention provides a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite, and the method has the advantages of low cost, good impurity removal effect and higher specific surface area of the prepared ferric phosphate.
The invention provides a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite, which comprises the following steps:
providing an aqueous solution of crude acid of phosphorite and a ferrous sulfate solution;
regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution;
mixing the phosphate solution with an oxidant to obtain a mixed solution;
dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake;
and sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate.
In some embodiments of the invention, the pH of the aqueous solution of crude acid of phosphorite is adjusted to 3-4.5 using a pH adjuster comprising one or more of ammonia, liquid base, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate, and potassium bicarbonate.
In some embodiments of the invention, the temperature of the heat treatment is 70-90 ℃; the heating treatment time is 0.5-2 h. Through pretreatment, al in crude acid of phosphorite can be removed 3+ 。
In some embodiments of the invention, the oxidizing agent is capable of oxidizing ferrous iron to ferric iron, the oxidizing agent being hydrogen peroxide and/or sodium peroxide;
the mol ratio of the oxidant to the ferrous sulfate is (1.15-1.25): 2, the ferrous iron can be oxidized more fully by the proper excessive oxidant.
In some embodiments of the invention, the molar ratio of iron in the ferrous sulfate solution to phosphorus in the mixed solution is (1-1.02): 1.
in some embodiments of the present invention, the drop time of the mixed solution is 10 to 40 minutes, and the nucleation state of the iron phosphate in the solution can be controlled by controlling the drop time of the mixed solution.
In some embodiments of the present invention, in the step C), after the mixed solution is completely added dropwise, a pH adjustor is added from the bottom of the slurry, and the pH of the mixed slurry is adjusted to 2.0 to 2.25; the pH regulator is added at the bottom, so that the particle size distribution of the product is finer.
The pH regulator comprises one or more of ammonia water, liquid alkali, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate and potassium bicarbonate.
In some embodiments of the invention, a pH regulator is added from the bottom to control the pH of the mixed slurry to be 2.0-2.25, and the mixed slurry is stirred for 45-55 min and then subjected to solid-liquid separation. The addition of the pH regulator after the synthesis reaction can lead the precipitated and nucleated ferric phosphate to be adsorbed and aggregated into a group, so that the crystal nucleus which does not grow completely is continuously extended until the crystal nucleus is complete. The specific surface area of the anhydrous ferric phosphate is increased,
in some embodiments of the invention, the aging temperature is 80 to 95 ℃; the heat preservation time of the aging is 1-3 h.
In some embodiments of the invention, the temperature of the calcination is 580-600 ℃; the calcination time is 1-3 h.
The invention provides a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite, which comprises the following steps: providing an aqueous solution of crude acid of phosphorite and a ferrous sulfate solution; regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution; mixing the phosphate solution with an oxidant to obtain a mixed solution; dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake; and sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate. The invention adopts the phosphorite crude acid to prepare a phosphate solution after a purification and one-time impurity removal process, then the pH value of the phosphorite crude acid is regulated to 3-4.5, most of Al impurities in the phosphorite crude acid are removed, the Al removal efficiency reaches 99.9%, and the phosphate solution is obtained after filtration and reacts with ferrous sulfate to prepare the ferric phosphate. The invention has the following advantages: (1) the crude acid price of phosphorite is low; (2) the filter residue can be used as phosphate fertilizer sales treatment without worrying about solid waste; (3) in the invention, the original dropping mode is changed in the synthesis process, firstly, the phosphate solution (phosphate pH 4.2) is dropped to react with the ferric salt solution completely, and then the pH regulator is added to enable the crystal nucleus which does not grow completely to extend continuously until the crystal nucleus is complete. The purpose is to make a part of phosphate react with ferric salt solution to precipitate at lower pH to form crystal nucleus, then adding pH regulator to nucleate and grow up rapidly, thus improving specific surface area of anhydrous ferric phosphate.
The foregoing description is only an overview of the technical solutions of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the above-mentioned and other objects, features and advantages of the present application more clearly understood, the following detailed description of the present application will be given.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic structural diagram of a synthetic dropping device for preparing battery grade ferric phosphate by using crude acid of phosphorite in the invention;
FIG. 2 is a schematic flow chart of the preparation of battery grade ferric phosphate by using crude acid of phosphorite;
FIG. 3 is a process flow diagram of the invention for preparing battery grade ferric phosphate from crude acid of phosphate rock;
FIG. 4 is an SEM image of anhydrous ferric phosphate prepared in example 1 of the present invention;
FIG. 5 is an SEM image of anhydrous ferric phosphate prepared in example 2-1 of the present invention;
FIG. 6 is an SEM image of anhydrous ferric phosphate prepared in example 3 of the invention;
FIG. 7 is an XRD diffraction pattern of anhydrous ferric phosphate prepared in example 1 (curve 1), example 2-1 (curve 2) and example 3 (curve 3) of the present invention;
FIG. 8 is an XRD diffraction pattern of anhydrous ferric phosphate prepared in comparative example 1 (curve 1) and comparative example 2 (curve 2) of the present invention;
FIG. 9 is an SEM image (100K) of the anhydrous ferric phosphate prepared in comparative example 1 of the present invention;
FIG. 10 is an SEM image (50K) of the anhydrous ferric phosphate prepared in comparative example 2 of the present invention;
reference numerals illustrate: 1 is a phosphate solution storage tank, 2 is a pH regulator storage tank, 3 is a stirring paddle, and 4 is a temperature sensor.
Detailed Description
Embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical solutions of the present application, and thus are only examples, and are not intended to limit the scope of protection of the present application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions.
In the description of the embodiments of the present application, the technical terms "first," "second," etc. are used merely to distinguish between different objects and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, a particular order or a primary or secondary relationship. In the description of the embodiments of the present application, the meaning of "plurality" is two or more unless explicitly defined otherwise.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
In the description of the embodiments of the present application, the term "and/or" is merely an association relationship describing an association object, which means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.
In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural sheets" refers to two or more (including two).
In the description of the embodiments of the present application, the orientation or positional relationship indicated by the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of describing the embodiments of the present application and for simplifying the description, rather than indicating or implying that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present application.
In the description of the embodiments of the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured" and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally formed; or may be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the embodiments of the present application will be understood by those of ordinary skill in the art according to the specific circumstances.
In the existing preparation method of the battery-grade ferric phosphate, the preparation process is often complex, more solid waste is generated, the treatment production cost is high, the impurity removal time is prolonged, the production efficiency is influenced, the phosphorus loss is large, or the obtained product has more impurities and the morphology, the specific surface area and the like of the product are suboptimal, so that the battery prepared from the ferric phosphate is also poor in performance.
In order to solve the technical problems in the preparation of the battery-grade ferric phosphate, the invention provides a method for preparing the battery-grade ferric phosphate by using crude acid of phosphorite, the preparation method is low in cost and good in impurity removal effect, and the prepared battery-grade ferric phosphate has higher specific surface area, so that the battery using the battery-grade ferric phosphate is better in performance.
Referring to fig. 2, the present invention provides a method for preparing battery grade iron phosphate using crude acid of phosphate ore, comprising the steps of:
s10, providing an aqueous solution of crude phosphorite acid and a ferrous sulfate solution;
s20, regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution;
s30, mixing the phosphate solution with an oxidant to obtain a mixed solution;
s40, dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake;
and S50, sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate.
In some embodiments of the present invention, in step S10, the crude phosphate rock acid is crude phosphoric acid obtained by leaching phosphate rock with sulfuric acid, and the crude phosphate rock acid is not subjected to an extraction process, wherein the content of phosphoric acid is about 65%, and the content of phosphorus pentoxide is about 46%, and contains a plurality of impurity elements such as aluminum, magnesium, manganese, sodium and iron.
In step S20, the method first needs to remove impurities from crude acid of phosphorite, and specifically adopts the following steps:
diluting coarse phosphorite acid with water to obtain coarse phosphorite acid water solution, dropping pH regulator into coarse phosphorite acid water solution to regulate pH to 3-4.5, heating to pre-treat, and adding Al 3+ Precipitating, and removing precipitated aluminum salt through solid-liquid separation to obtain a phosphate solution.
In this process, the reaction equation that mainly occurs is as follows:
①H 3 PO 4 +Al 3+ ＝AlPO 4 +3H + ；
②H 3 PO 4 +NH 3 ·H 2 O＝NH 4 H 2 PO 4 +H 2 O；
③NH 3 ·H 2 O+H + ＝NH 4 + +H 2 O；
in some embodiments of the invention, the mass ratio of the crude acid of the phosphate rock to the water is 1: (1-2), preferably 1:1, wherein the pH regulator is one or more of ammonia water, liquid alkali, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate and potassium bicarbonate, the dropping time of the pH regulator is controlled to be 30-50 min, preferably 35-45 min, such as 35min,40min,45min and the like, or a range value with any of the above values as an upper limit or a lower limit; the pH regulator is added dropwise to regulate the pH of the solution to 3-4.5, preferably 4-4.5, and the dosage of the pH regulator is not particularly limited, so that the pH value of the aqueous solution of the crude acid of the phosphorite can be regulated within a required range.
In step S20 of the present invention, after the adjustment of the pH of the aqueous solution of the crude acid of the phosphorus ore is completed, the aqueous solution of the crude acid of the phosphorus ore is subjected to a heat treatment to remove Al in the aqueous solution of the crude acid of the phosphorus ore 3+ After the precipitation is finished, carrying out solid-liquid separation to obtain a phosphate solution after impurity removal.
In some embodiments of the invention, the temperature of the heat treatment is 70 to 90 ℃, preferably 75 to 85 ℃, such as 75 ℃,80 ℃,85 ℃, etc., or ranges from any of the above values to an upper or lower limit; the time of the heating treatment is 0.5 to 2 hours, preferably 1 to 1.5 hours.
It is understood that in the present invention, the phosphate solution after solid-liquid separation can be diluted by adding pure water to control the mass content of phosphorus in the solution to 5-8%, and in this concentration range, the phosphate and ferrous sulfate have a good reaction effect, while in the case of too low a concentration, the reaction rate of ferrous sulfate and phosphate in the solution is insufficient, and in the case of too high a concentration, the phosphorus salt is liable to crystallize, which is unfavorable for pipeline transportation.
After the impurity removal of the phosphorite crude acid is completed, the invention takes ferrous sulfate solution as base solution and peroxide as oxidant, and the mixed solution of phosphate solution and oxidant is dripped into the ferrous sulfate solution for reaction.
In some embodiments of the present invention, the ferrous sulfate solution may be prepared by conventional methods, for example, using a ferrous sulfate heptahydrate crystal as a titanium white byproduct as an iron source raw material, dissolving in pure water, adding a pH adjustor, adjusting the pH of the ferrous sulfate solution to 3-5 to remove impurity titanium and aluminum ions in the ferrous sulfate solution, and then performing solid-liquid separation to obtain a ferrous sulfate solution;
in some embodiments of the present invention, the pH adjuster is preferably one or more of reduced iron powder, ammonia water, sodium bicarbonate, caustic soda flakes, ammonium bicarbonate, and potassium bicarbonate.
In some embodiments of the invention, the ferrous sulfate solution is used at a mass concentration of 180 to 230g/kg, preferably 190 to 220g/kg, such as 190g/kg,200g/kg,210g/kg,220g/kg, etc., or a range value having any of the above values as an upper or lower limit; when the concentration is too high, the temperature is lower than 20 ℃ and is easy to crystallize, so that the pipeline transportation is not facilitated, and impurity ions in the ferrous sulfate solution with too low concentration are relatively high, so that the impurity ions of the anhydrous ferric phosphate are relatively high. When the concentration of the purified ferrous sulfate solution is not within the above range, pure water may be added for dilution.
In the steps S30 and S40, firstly, mixing a phosphate solution and an oxidant under stirring to obtain a mixed solution, then, dripping the mixed solution into a ferrous sulfate solution, carrying out a synthetic reaction to obtain a mixed slurry, oxidizing a ferrous iron source, then, precipitating to prepare ferric phosphate, controlling the time of dripping synthesis, adding a pH regulator after the dripping is finished, controlling the pH of the slurry to be 2.0-2.25, continuing stirring, and then, carrying out solid-liquid separation to obtain a filter cake.
The pH value of the slurry after the phosphate and ferrous sulfate react is controlled to be 3-4.5, so that the pH value of the slurry after the phosphate and ferrous sulfate react is ensured to be 1.2-1.5, the phosphate and ferrous sulfate react to form precipitation nucleation at the lower pH value, then the time for dropwise addition is controlled, a pH regulator is dropwise added after the completion of dropwise addition of the phosphate, the pH value of the slurry is regulated to be 2.0-2.25, and the precipitation nucleation ferric phosphate is adsorbed and aggregated to form clusters, so that the incompletely grown crystal nuclei extend continuously until the complete crystal nuclei are obtained. The specific surface area of the anhydrous ferric phosphate is increased, and the performance of the anhydrous ferric phosphate is improved.
In some embodiments of the invention, the oxidizing agent is a peroxide, such as hydrogen peroxide and/or sodium peroxide, for example, in the invention, a hydrogen peroxide solution and/or sodium peroxide solids may be used, wherein the hydrogen peroxide solution has a mass concentration of 20 to 30wt%, preferably 23 to 28%. Adding an excessive amount of 15-25% of oxidant according to the metering ratio of the reaction of the oxidant and ferrous sulfate, namely, the molar ratio of the oxidant to the ferrous sulfate is (1.15-1.25): 2, preferably in a molar ratio of (1.2 to 1.22): 2, such as 1.2:2,1.21:2,1.22:2, etc., or a range value having any of the above values as an upper limit or a lower limit.
In some embodiments of the invention, the molar ratio of iron in the ferrous sulfate solution to phosphorus in the mixed solution is (1-1.02): 1, preferably (1 to 1.01): 1.
in some embodiments of the invention, the dropwise addition of the pH adjuster to the mixed slurry is a process of conversion of ferric iron to ferric phosphate with concomitant formation of small amounts of ferric hydroxide, as ferric hydroxide on the one hand has the ability to adsorb anions. Therefore, if iron phosphate with higher purity is to be prepared, the synthesis reaction mode and the dripping time are strictly controlled to reduce the generation of iron hydroxide, and the dripping time of the mixed solution is controlled to be 10-40 min, preferably 15-20 min, such as 15min,16min,17min,18min,19min,20min and the like, or a range value with any of the above values as an upper limit or a lower limit.
In step S40, after the addition of the drops is finished to obtain mixed slurry, adding a pH regulator from the bottom of the mixed slurry to enable the particle size distribution of the product to be more uniform and the particle size distribution to be narrower, wherein the pH regulator comprises one or more of ammonia water, liquid alkali, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate and potassium bicarbonate; the molar ratio of the phosphate in the phosphate solution to the pH regulator is (10-15), preferably (11-14): 1, more preferably (12 to 13): 1.
in some embodiments of the invention, the pH of the slurry is controlled to be 2.0-2.25 after the addition of the pH adjustor is completed, and stirring is continued for 45-55 min, such as 45min,46min,47min,48min,49min,50min,51min,52min,53min,54min,55min, etc., or a range value with any of the above values as an upper or lower limit.
In step S40, the pH is adjusted to 2.0 to 2.25, and then the mixture is stirred, and after completion of the stirring, solid-liquid separation is performed to obtain a cake.
In step S50, a washing, preferably a water washing, is performed on the filter cake obtained in step S40, and solid-liquid separation is performed after the water washing to obtain a washed filter cake; adding pure water and phosphoric acid into the filter cake after primary washing for pulping, dispersing the filter cake uniformly, heating for aging, converting amorphous in the synthetic slurry into stable crystal form ferric phosphate, and carrying out solid-liquid separation to obtain the aged ferric phosphate filter cake.
In some embodiments of the invention, the aging temperature is preferably 80 to 95 ℃, more preferably 85 to 90 ℃, and the aging incubation time is preferably 1 to 3 hours, more preferably 1 to 2 hours. The invention has no special requirement on the adding amount of phosphoric acid, and the initial pH value of aging is controlled to be less than 2.0.
In step S50, the present invention sequentially performs secondary washing, drying and calcination on the aged iron phosphate filter cake to obtain battery-grade anhydrous iron phosphate.
In some embodiments of the invention, the second wash is preferably a water wash, and the solid-liquid separation is performed after the water wash to obtain a filter cake after the second wash.
In some embodiments of the invention, the drying is preferably a drying at a temperature of 90-120 ℃, preferably 100-110 ℃; the drying time is 6-9 h, preferably 7-8 h.
In the present invention, the calcination temperature is 580 to 600 ℃, preferably 590 to 595 ℃, and the calcination time is 1 to 3 hours, preferably 2 to 2.5 hours.
In some embodiments of the present invention, the solid-liquid separation described above may be performed by solid-liquid separation methods commonly used in the art, and the present invention is not described herein.
The battery grade ferric phosphate obtained by the preparation method has the particle size D50 less than 5 mu m; specific surface area of 8-11 m 2 /g。
The invention provides a method for preparing battery-grade ferric phosphate by using crude acid of phosphorite, which comprises the following steps: providing an aqueous solution of crude acid of phosphorite and a ferrous sulfate solution; regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution; mixing the phosphate solution with an oxidant to obtain a mixed solution; dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake; and sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate. The invention adopts the phosphorite crude acid to prepare a phosphate solution after a purification and one-time impurity removal process, then the pH value of the phosphorite crude acid is regulated to 3-4.5, most of Al impurities in the phosphorite crude acid are removed, the Al removal efficiency reaches 99.9%, and the phosphate solution is obtained after filtration and reacts with ferrous sulfate to prepare the ferric phosphate. The invention has the following advantages: (1) the crude acid price of phosphorite is low; (2) the filter residue can be used as phosphate fertilizer sales treatment without worrying about solid waste; (3) in the invention, the original dropping mode is changed in the synthesis process, firstly, the phosphate solution (pH 4.2) is dropped to react with the ferric salt solution completely, and then the pH regulator is added to enable the crystal nucleus which does not grow completely to extend continuously until the crystal nucleus is complete. The purpose is to make a part of phosphate react with ferric salt solution to precipitate at lower pH to form crystal nucleus, then adding pH regulator to nucleate and grow up rapidly, thus improving specific surface area of anhydrous ferric phosphate.
In order to further illustrate the present invention, the following examples are provided to illustrate and not to limit the present application. The examples are not to be construed as limiting the specific techniques or conditions described in the literature in this field or as per the specifications of the product. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
The crude acid components of the phosphorite used in the following examples are shown in Table 1:
TABLE 1 data for detecting the components of crude acid of raw material phosphorite
Example 1
Impurity removal treatment for crude acid of phosphorite
1000g of crude phosphorite acid with the content of 67.83 percent is taken, pure water with the same proportion is added, the mixture is stirred and mixed uniformly, ammonia water is added to adjust the pH value to 4.2, the mixture is reacted at 80 ℃ for 45min and then subjected to solid-liquid separation, clear liquid is obtained as phosphate solution, and 184.3g (dry slag) of filter residue can be used as phosphate fertilizer sales treatment;
impurity removal treatment for ferrous sulfate
Taking 1200g of titanium dioxide byproduct ferrous sulfate heptahydrate, adding 1000g of pure water, stirring in a 45 ℃ water bath for dissolution, adjusting the pH value to 4.2, and filtering to obtain a clear ferrous sulfate solution;
synthesis reaction
Adding pure water into the purified phosphate solution (pH 3.5) to dilute the solution until the phosphorus content is about 5.5%, adding 27% hydrogen peroxide into the phosphate solution, adding the solution in an excess of 20% according to the reaction metering ratio of ferrous iron and hydrogen peroxide, and stirring and uniformly mixing.
Adding pure water into the purified ferrous sulfate solution to dilute to 1mol/L, taking the pure water as a base solution, taking phosphate solution added with oxidant as a drop solution, and dropping the phosphate solution into the ferrous sulfate solution, wherein the addition amounts of the two solutions are as follows n (P): the ratio of n (Fe) =1.02:1 was controlled, and the time of dropwise addition was controlled to be 10min.
Ammonia water is used as a pH regulator, and after the dropwise addition reaction is finished, the pH regulator is dropwise added (the pH regulator is added to the bottom of the solution), and the addition amount of phosphate and ammonia water is controlled according to the proportion of 12:1. And controlling the pH value to 2.0 after the dripping is finished, stirring for 50min, washing, pulping, aging, washing twice, drying to obtain ferric phosphate dihydrate, and calcining to obtain anhydrous ferric phosphate.
Example 2
Anhydrous ferric phosphate was prepared as in example 1, except that in the "crude acid removal of phosphorus ore" step, a pH adjustor was used to control the pH of the slurry to 4.2. After the reaction is finished, dropwise adding a pH regulator (the pH regulator is added to the bottom of the solution) to control the dropwise adding time to be 15min, controlling the synthetic pH to be 2.2 after the dropwise adding is finished, stirring for 50min, and then washing, pulping, aging, washing for two times, drying and calcining to obtain the anhydrous ferric phosphate.
Two parallel experiments (respectively referred to as examples 2-1 and 2-2) were performed according to the technical scheme in example 2, and the particle size detection data of the phosphate mixed solution and the slurry after the dropping of the pH adjustor were detected in the "synthetic reaction" step according to GB-T41949-2022, and the results are shown in tables 2 to 3.
Table 2 detection data of slurry to which phosphate was added dropwise in the synthesis step
TABLE 3 detection data for slurry with pH adjustor added dropwise during Synthesis procedure
From the examination data in tables 2 and 3, it can be seen that the particle size of the pH adjustor after the dropping was significantly finer than that of the phosphate after the dropping. For example, the D50 particle size of the pH regulator after the dripping is 20-40 μm smaller than the D50 particle size of the phosphate after the dripping, and the D100 particle size of the pH regulator after the dripping is 180-400 μm smaller than the D100 particle size of the phosphate after the dripping.
According to the invention, the pH regulator is used after a certain period of synthesis reaction, so that the particle size of the synthesized ferric phosphate particles is obviously reduced, the size difference of the synthesized ferric phosphate particles is larger, and the specific surface area of the anhydrous ferric phosphate product is improved.
Example 3
Anhydrous ferric phosphate is prepared by the method in the embodiment 1, except that in the step of removing impurities from crude acid of phosphorite, a pH regulator is used for controlling the pH value of slurry to be 4.0, the pH regulator is added dropwise after the reaction is finished (the pH regulator is added to the bottom of the solution), the synthetic dropwise adding time is controlled to be 30min, the synthetic pH value is controlled to be 2.2 after the dropwise adding is finished, and then the mixture is stirred for 50min, and then washing, beating, aging, secondary washing, drying and calcining are carried out to obtain anhydrous ferric phosphate.
Example 4
Anhydrous ferric phosphate is prepared by the method in the embodiment 1, except that in the step of removing impurities from crude acid of phosphorite, a pH regulator is used for controlling the pH value of slurry to be 4.2, the pH regulator is added dropwise after the reaction is finished (the pH regulator is added to the bottom of the solution), the synthetic dropwise adding time is controlled to be 30min, the synthetic pH value is controlled to be 2.2 after the dropwise adding is finished, and then the mixture is stirred for 50min, and then washing, beating, aging, secondary washing, drying and calcining are carried out to obtain anhydrous ferric phosphate.
Example 5
Anhydrous ferric phosphate is prepared by the method in the embodiment 1, except that in the step of removing impurities from crude acid of phosphorite, a pH regulator is used for controlling the pH value of slurry to be 4.2, the pH regulator is added dropwise after the reaction is finished (the pH regulator is added to the bottom of the solution), the synthetic dropwise adding time is controlled to be 15min, the synthetic pH value is controlled to be 2.0 after the dropwise adding is finished, and then the mixture is stirred for 50min, and then washing, beating, aging, secondary washing, drying and calcining are carried out to obtain anhydrous ferric phosphate.
Example 6
Anhydrous ferric phosphate was prepared as in example 1, except that in the "crude acid impurity removal from phosphate rock" step, pH of the slurry was controlled to 3.5 using a pH adjustor, and 178.3g (dry residue) of the resulting residue was treated as phosphate fertilizer for sale.
Example 7
Anhydrous ferric phosphate is prepared as in example 1, except that in the "synthetic reaction" step, the pH is controlled to 2.0 after the dropwise addition, and then 30min,40min and 55min are stirred respectively, followed by primary washing, beating, aging, secondary washing, drying and calcination to obtain anhydrous ferric phosphate.
The results are shown in Table 4.
TABLE 4 elemental measurement data for one-wash mother liquor obtained at different agitation times
Note that: the "primary washing mother liquor" refers to washing wastewater generated after the washing step of "primary washing".
As is clear from Table 4, the impurity element was not precipitated during the synthesis and remained in the mother liquor. The Fe element shows that the longer the stirring time is, the Fe in the mother solution is relatively reduced, and the Fe participates in the reaction along with the prolongation of the stirring time. The stirring time after synthesis can influence the reaction rate, the shorter the time is, the reaction is not complete enough, and the long time influences the beat.
Comparative example 1
Anhydrous ferric phosphate was prepared as in example 2, except that in the "synthetic reaction" step, a pH adjuster was added dropwise above the level of the solution.
Comparative example 2
Anhydrous ferric phosphate was prepared as in example 2, except that in the "crude acid impurity removal from phosphate rock" step, the pH of the slurry was controlled to 7.0 using a pH adjustor, and 202.5g (dry residue) of the resulting residue was treated as phosphate fertilizer for sale.
The phosphate solutions and filter residues after the impurity removal in example 1, comparative example 1 and comparative example 3 were subjected to component detection according to GBT 23942-2009, and the results are shown in tables 5 to 6,
TABLE 5 phosphate detection data after impurity removal and filtration of crude acid of phosphate rock at different pH values
TABLE 6 data for detecting residue after impurity removal and filtration of crude acid of phosphorite at different pH values
As can be seen from the detection data in tables 5 and 6, the present invention changes the pH of the crude acid of phosphorite to 3 to 4.5, and first, the present invention can remove the impurity element F, al, mg, mn in the crude acid; second, because Al is amphoteric, too high a pH will form soluble meta-aluminates that are carried into the finished product; thirdly, the pH value is set to be 3-4.5, so that impurities can be removed effectively at one time, the process flow is reduced, and the impurities are removed by twice filtration when the pH is regulated to be 7+/-0.1 in comparative example 2, so that the utilization rate of phosphorus is greatly reduced.
According to the embodiment 1 and the embodiment 6, the efficiency of removing Al impurities reaches more than 99%, the process is simple, the impurities are removed in one step, and the obtained filter residues can be subjected to sales treatment. The content of each impurity in the anhydrous detection data is close to that in the anhydrous ferric phosphate prepared by purifying industrial monoammonium phosphate with high price to obtain a phosphorus source.
The battery grade iron phosphate products prepared in examples 1 to 6 and comparative examples 2 to 3 were examined, and the results are shown in tables 7 to 8.
TABLE 7 component detection data for Battery grade Anhydrous ferric phosphate
Table 8 data for detecting performance parameters of battery grade anhydrous iron phosphate
Note that: in tables 7 and 8, the product corresponding to "example 2" was the anhydrous ferric sulfate product prepared in example 2-1 of two parallel tests.
From the analysis of the detection data in tables 7 to 8, when the impurity removal pH of the crude acid of the phosphorite is adjusted to 3.5, impurity ions in the raw materials are not completely removed, about 300pp of Al in the phosphate solution is introduced into the finished product, and the particle size and specific surface area data of the product are affected to different degrees, so that the control of the impurity removal pH of the crude acid of the phosphorite has an important influence on the performance of the battery-grade ferric phosphate.
In comparative example 1, the pH was adjusted by adding ammonia water after the phosphorous salt solution was added dropwise, and the pH could not be adjusted by adding ammonia water after the phosphate was added dropwise because the elemental analysis of the finished product was performed or some Al was carried into the finished product.
Comparative example 2 when the pH of the crude acid of the phosphorite was adjusted to 7 (comparative example 1), the Al in the finished product had exceeded 100ppm, since Al is amphoteric, and too high a pH would form a soluble meta-aluminate that was carried into the finished product. If the impurity is removed by two times of filtration: 1. the impurity removing procedure is added, and the process time is prolonged; 2. there is a partial loss of phosphorus and increased costs.
The present application is not limited to the above embodiment. The above embodiments are merely examples, and embodiments having substantially the same configuration and the same effects as those of the technical idea within the scope of the present application are included in the technical scope of the present application. Further, various modifications that can be made to the embodiments and other modes of combining some of the constituent elements in the embodiments, which are conceivable to those skilled in the art, are also included in the scope of the present application within the scope not departing from the gist of the present application.
Claims (10)
1. A method for preparing battery grade ferric phosphate by using crude acid of phosphorite, comprising the following steps:
providing an aqueous solution of crude acid of phosphorite and a ferrous sulfate solution;
regulating the pH value of the aqueous solution of the crude acid of the phosphorite to 3-4.5, heating, and carrying out solid-liquid separation to obtain a phosphate solution;
mixing the phosphate solution with an oxidant to obtain a mixed solution;
dropwise adding the mixed solution into the ferrous sulfate solution to obtain mixed slurry, adjusting the pH of the mixed slurry to 2.0-2.25, and carrying out solid-liquid separation after stirring to obtain a filter cake;
and sequentially performing primary washing, aging, secondary washing, drying and calcination on the filter cake to obtain the battery-grade ferric phosphate.
2. The method according to claim 1, characterized in that the pH of the aqueous solution of the crude acid of phosphorite is adjusted to 3-4.5 using a pH adjuster comprising one or several of ammonia water, liquid base, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate and potassium bicarbonate.
3. The method according to claim 2, wherein the temperature of the heat treatment is 70-90 ℃; the heating treatment time is 0.5-2 h.
4. The method according to claim 1, wherein the oxidizing agent is hydrogen peroxide and/or sodium peroxide;
the mol ratio of the oxidant to the ferrous sulfate is (1.15-1.25): 2.
5. the method according to claim 1, wherein the molar ratio of iron in the ferrous sulfate solution to phosphorus in the mixed solution is (1-1.02): 1.
6. the method according to claim 5, wherein the mixed solution is dropped for 10 to 40 minutes.
7. The method according to claim 6, wherein after the completion of the dropwise addition of the mixed solution, a pH adjuster is added from the bottom of the slurry to adjust the pH of the mixed slurry to 2.0 to 2.25;
the pH regulator comprises one or more of ammonia water, liquid alkali, ammonium carbonate, ammonium bicarbonate, sodium carbonate, sodium bicarbonate, potassium carbonate and potassium bicarbonate.
8. The method according to claim 7, wherein the pH of the mixed slurry is controlled to be 2.0-2.25 by adding a pH adjustor from the bottom, stirring for 45-55 min, and then performing solid-liquid separation.
9. The method of claim 1, wherein the aging temperature is 80-95 ℃; the heat preservation time of the aging is 1-3 h.
10. The method of claim 1, wherein the temperature of calcination is 580-600 ℃; the calcination time is 1-3 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311745620.3A CN117550575A (en) | 2023-12-18 | 2023-12-18 | Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311745620.3A CN117550575A (en) | 2023-12-18 | 2023-12-18 | Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117550575A true CN117550575A (en) | 2024-02-13 |
Family
ID=89823238
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311745620.3A Pending CN117550575A (en) | 2023-12-18 | 2023-12-18 | Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117550575A (en) |
-
2023
- 2023-12-18 CN CN202311745620.3A patent/CN117550575A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107720716B (en) | The technique for preparing battery-level lithium carbonate and ferric phosphate from crude product lithium phosphate recycling lithium phosphorus | |
| RU2530126C2 (en) | Production of iron orthophosphate | |
| CN101821197B (en) | Iron(III) orthophosphate for li ion accumulators | |
| CN112645299A (en) | Preparation method and application of iron phosphate | |
| CN110683528B (en) | Regeneration method of iron phosphate waste | |
| US8420215B2 (en) | Cyclic process for the preparation of barium sulphate and lithium metal phosphate compounds | |
| WO2022242186A1 (en) | Method for preparing high-purity iron phosphate by using ferrophosphorus waste | |
| CN108455547A (en) | A kind of low impurity high ferro phosphorus is than greatly than the preparation method of table battery-grade iron phosphate | |
| CN110342483B (en) | Method for preparing battery-grade iron phosphate by using lithium phosphate waste | |
| CN113104827B (en) | Method for preparing battery-grade anhydrous iron phosphate from industrial ammonium phosphate clear solution or industrial ammonium phosphate mother solution | |
| CN113460989B (en) | Battery-grade iron phosphate and preparation method thereof | |
| US20240021904A1 (en) | Recycling method and use of lithium iron phosphate (lfp) waste | |
| CN113353907A (en) | Ferric phosphate precursor and preparation method and application thereof | |
| CN113184819A (en) | Method for preparing iron phosphate by utilizing phosphorite and preparation method of lithium iron phosphate | |
| CN115477293B (en) | Preparation method of anhydrous ferric phosphate with low impurity and high specific surface area | |
| CN113184820A (en) | Method for preparing iron phosphate by using titanium dioxide byproduct ferrous sulfate | |
| CN115043383A (en) | High-tap-density battery-grade iron phosphate and preparation method thereof | |
| CN113772650A (en) | Preparation method and application of lithium iron phosphate | |
| CN113526480A (en) | Method for preparing ferrous phosphate from titanium dioxide byproduct | |
| CN114516625A (en) | Iron phosphate and preparation method and application thereof | |
| CN108557792B (en) | A kind of preparation method of cladded type iron manganese phosphate | |
| CN111792635A (en) | Preparation method of anhydrous iron phosphate | |
| CN117550575A (en) | Method for preparing battery-grade ferric phosphate by using crude acid of phosphorite | |
| CN115799696A (en) | Method for pretreating waste electrolyte after disassembling lithium ion battery and method for fully recovering lithium, fluorine and phosphorus in waste electrolyte | |
| CN114956189B (en) | Preparation method of battery-grade manganese sulfate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |