CN100339299C - Method for purification of phosphoric acid - Google Patents
Method for purification of phosphoric acid Download PDFInfo
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- CN100339299C CN100339299C CNB2005101136508A CN200510113650A CN100339299C CN 100339299 C CN100339299 C CN 100339299C CN B2005101136508 A CNB2005101136508 A CN B2005101136508A CN 200510113650 A CN200510113650 A CN 200510113650A CN 100339299 C CN100339299 C CN 100339299C
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- phosphoric acid
- arsenic
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- acid
- hydrogen halide
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- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 title claims abstract description 259
- 229910000147 aluminium phosphate Inorganic materials 0.000 title claims abstract description 124
- 238000000034 method Methods 0.000 title claims abstract description 106
- 238000000746 purification Methods 0.000 title claims abstract description 26
- 229910052785 arsenic Inorganic materials 0.000 claims abstract description 64
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims abstract description 64
- 229910000039 hydrogen halide Inorganic materials 0.000 claims abstract description 44
- 239000012433 hydrogen halide Substances 0.000 claims abstract description 44
- 150000001875 compounds Chemical class 0.000 claims abstract description 20
- 230000002378 acidificating effect Effects 0.000 claims abstract description 15
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 22
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims description 18
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims description 18
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims description 4
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims description 4
- VMQMZMRVKUZKQL-UHFFFAOYSA-N Cu+ Chemical compound [Cu+] VMQMZMRVKUZKQL-UHFFFAOYSA-N 0.000 claims description 3
- 238000005422 blasting Methods 0.000 claims description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract description 42
- 239000011734 sodium Substances 0.000 abstract description 34
- 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 abstract description 29
- 229910052708 sodium Inorganic materials 0.000 abstract description 29
- DLYUQMMRRRQYAE-UHFFFAOYSA-N phosphorus pentoxide Inorganic materials O1P(O2)(=O)OP3(=O)OP1(=O)OP2(=O)O3 DLYUQMMRRRQYAE-UHFFFAOYSA-N 0.000 abstract description 21
- 239000000377 silicon dioxide Substances 0.000 abstract description 21
- 229920000137 polyphosphoric acid Polymers 0.000 abstract description 17
- 229910001385 heavy metal Inorganic materials 0.000 abstract description 16
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 abstract description 8
- 238000001914 filtration Methods 0.000 abstract description 6
- 238000007872 degassing Methods 0.000 abstract description 3
- 238000001556 precipitation Methods 0.000 abstract description 2
- YWEUIGNSBFLMFL-UHFFFAOYSA-N diphosphonate Chemical compound O=P(=O)OP(=O)=O YWEUIGNSBFLMFL-UHFFFAOYSA-N 0.000 abstract 1
- 235000011007 phosphoric acid Nutrition 0.000 description 116
- 239000002253 acid Substances 0.000 description 46
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 21
- 229960001866 silicon dioxide Drugs 0.000 description 16
- 235000012239 silicon dioxide Nutrition 0.000 description 16
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 15
- 239000007789 gas Substances 0.000 description 12
- 239000011521 glass Substances 0.000 description 12
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 11
- 239000011651 chromium Substances 0.000 description 10
- 239000000047 product Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- 230000015271 coagulation Effects 0.000 description 6
- 238000005345 coagulation Methods 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 6
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 5
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 5
- 229910004298 SiO 2 Inorganic materials 0.000 description 5
- 239000011733 molybdenum Substances 0.000 description 5
- 239000002367 phosphate rock Substances 0.000 description 5
- 230000002829 reductive effect Effects 0.000 description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 150000001495 arsenic compounds Chemical class 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 4
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 4
- 229910001507 metal halide Inorganic materials 0.000 description 4
- 150000005309 metal halides Chemical class 0.000 description 4
- 229910052750 molybdenum Inorganic materials 0.000 description 4
- 229910052759 nickel Inorganic materials 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- -1 Sodium sulfhydrate Chemical class 0.000 description 3
- 238000007664 blowing Methods 0.000 description 3
- 239000003814 drug Substances 0.000 description 3
- 239000012776 electronic material Substances 0.000 description 3
- 230000002349 favourable effect Effects 0.000 description 3
- 230000036571 hydration Effects 0.000 description 3
- 238000006703 hydration reaction Methods 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 238000009616 inductively coupled plasma Methods 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000006068 polycondensation reaction Methods 0.000 description 3
- 239000012488 sample solution Substances 0.000 description 3
- HYHCSLBZRBJJCH-UHFFFAOYSA-M sodium hydrosulfide Chemical compound [Na+].[SH-] HYHCSLBZRBJJCH-UHFFFAOYSA-M 0.000 description 3
- 235000010265 sodium sulphite Nutrition 0.000 description 3
- XPDICGYEJXYUDW-UHFFFAOYSA-N tetraarsenic tetrasulfide Chemical compound S1[As]2S[As]3[As]1S[As]2S3 XPDICGYEJXYUDW-UHFFFAOYSA-N 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 2
- CPELXLSAUQHCOX-UHFFFAOYSA-N Hydrogen bromide Chemical compound Br CPELXLSAUQHCOX-UHFFFAOYSA-N 0.000 description 2
- 229910019142 PO4 Inorganic materials 0.000 description 2
- DPDMMXDBJGCCQC-UHFFFAOYSA-N [Na].[Cl] Chemical compound [Na].[Cl] DPDMMXDBJGCCQC-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- VUEDNLCYHKSELL-UHFFFAOYSA-N arsonium Chemical compound [AsH4+] VUEDNLCYHKSELL-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000005342 ion exchange Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002156 mixing Methods 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
- 238000002360 preparation method Methods 0.000 description 2
- 238000012207 quantitative assay Methods 0.000 description 2
- 150000003388 sodium compounds Chemical class 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- OBSZRRSYVTXPNB-UHFFFAOYSA-N tetraphosphorus Chemical compound P12P3P1P32 OBSZRRSYVTXPNB-UHFFFAOYSA-N 0.000 description 2
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical class Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 description 2
- DJHGAFSJWGLOIV-UHFFFAOYSA-N Arsenic acid Chemical compound O[As](O)(O)=O DJHGAFSJWGLOIV-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910021543 Nickel dioxide Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- IKWTVSLWAPBBKU-UHFFFAOYSA-N a1010_sial Chemical compound O=[As]O[As]=O IKWTVSLWAPBBKU-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 229940000488 arsenic acid Drugs 0.000 description 1
- 229960002594 arsenic trioxide Drugs 0.000 description 1
- GOLCXWYRSKYTSP-UHFFFAOYSA-N arsenic trioxide Inorganic materials O1[As]2O[As]1O2 GOLCXWYRSKYTSP-UHFFFAOYSA-N 0.000 description 1
- 238000011088 calibration curve Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- AYTAKQFHWFYBMA-UHFFFAOYSA-N chromium(IV) oxide Inorganic materials O=[Cr]=O AYTAKQFHWFYBMA-UHFFFAOYSA-N 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 229910003439 heavy metal oxide Inorganic materials 0.000 description 1
- 229910000042 hydrogen bromide Inorganic materials 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- QXYJCZRRLLQGCR-UHFFFAOYSA-N molybdenum(IV) oxide Inorganic materials O=[Mo]=O QXYJCZRRLLQGCR-UHFFFAOYSA-N 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000005416 organic matter Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
Landscapes
- Silicon Compounds (AREA)
- Removal Of Specific Substances (AREA)
Abstract
A method for purification of phosphoric acid, characterized as comprising contacting a crude phosphoric acid containing arsenic with hydrogen halide to remove the arsenic from the crude phosphoric acid; and a method for purification of phosphoric acid, characterized as comprising contacting a crude phosphoric acid containing arsenic with hydrogen halide in the presence of a compound which can produce hydrogen halide under an acidic condition. The above methods provide novel methods for removing arsenic from a crude phosphoric acid which does not require any of a filtering and a degassing processes which are necessary in the sulfide precipitation method, does not give a large amount of residual sodium, can be applied to a crude phosphoric acid having a high concentration of phosphorus pentoxide, particularly to polyphosphoric acid, and can be practiced at a low cost; and thus they can be used for producing a high purity polyphosphoric acid having an arsenic (As) content of 1 ppm or less and also low contents of heavy metals, silica, sodium and the like.
Description
The application is Chinese patent application 99815152.1 (applying date 1999.12.24; Priority date 1998.12.28,1999.8.17, international application no PCT/JP99/07312, exercise question are " method of purification of phosphoric acid and high purity polyphosphoric acid ") divide an application.
Technical field
The present invention relates to the method for purification of phosphoric acid, this method can reduce the content of harmful heavy metal, particularly arsenic effectively, and relates to the high purity polyphosphoric acid that obtains thus, and it is expected at food, and medicine and field of electronic materials are used widely.
Background technology
Produce the method for phosphoric acid, known have wet method and dry method, and one of industrial these methods of employing are produced phosphoric acid.In wet method, Rock Phosphate (72Min BPL) is dissolved in the sulfuric acid, filter out the gypsum composition, obtain the dilute phosphoric acid of lower concentration, and dilute phosphoric acid is concentrated to required level, obtain phosphoric acid.In dry method, Rock Phosphate (72Min BPL) is reduced in electric furnace, obtain yellow phosphorus, its burning obtains phosphoric anhydride, then the phosphoric anhydride hydration is obtained phosphoric acid.Usually, wet method does not need reduction or burning, and it is favourable being considered to aspect production cost.Dry method has reduced the pollution from the impurity of Rock Phosphate (72Min BPL) because produce via phosphoric anhydride, and it is favourable being considered to aspect quality.Yet, in any production method, all containing arsenic in the phosphoric acid that obtains from Rock Phosphate (72Min BPL) or phosphoric anhydride, it is deleterious to human body, is about tens ppm usually, carries out dearsenification according to the purposes employing sulfide agglomerative method of phosphoric acid.Conventional arsenic removing method only is applicable to P
2O
5Concentration is up to about 60% phosphoric acid.
High concentrations of phosphoric acid, particularly Tripyrophosphoric acid (P
2O
5Concentration is not less than 72.4%), as phosphoric acid, also adopt aforesaid wet method or dry production.With the Tripyrophosphoric acid of dry production,, demonstrate lower heavy metal usually, silicon-dioxide and sodium content owing to produce via phosphoric anhydride.Yet because conventional arsenic removing method is not suitable for high concentrations of phosphoric acid, it contains the arsenic from phosphoric anhydride of the 5-100ppm that has an appointment.Tripyrophosphoric acid with wet production demonstrates the low arsenic content that is lower than 1ppm, because can use conventional arsenic removing method before concentrating.On the other hand, demonstrate to its characteristic the high-load heavy metal that derives from Rock Phosphate (72Min BPL), silicon-dioxide and sodium.High concentrations of phosphoric acid, particularly Tripyrophosphoric acid is characterized in that demonstrating low arsenic content and low heavy metal, and silicon-dioxide and sodium content also do not obtain.
As the P that obtains with dry method
2O
5Concentration is up to about 60% phosphoric acid, and when carrying out dearsenification and handle and concentrate with conventional sulfide coagulation method etc., estimation can obtain having the arsenic of low levels, heavy metal, the phosphoric acid of silicon-dioxide and sodium.Yet this production method also is not applied in the practice.This is that this is extremely disadvantageous from economic point of view, because equipment cost and operating cost are all high because need be used to burn and the device of hydration yellow phosphorus and be used for highly concentrating the device of gained phosphoric acid.
The arsenic that in phosphoric acid and Tripyrophosphoric acid, contains, at food, medicine, the highly purified Application for Field of needs such as electronic material is disadvantageous especially.And recent years has been owing to given great attention to environmental problem, need have the phosphoric acid of low arsenic content and Tripyrophosphoric acid as industrialization phosphoric acid, is used for metal finishing, dyestuff processing etc.Therefore, need a kind of arsenic removing method that can effectively turn round with low cost.
Known from phosphoric acid the method for dearsenification comprise: (1) sulfide coagulation, (2) solvent extration and (3) ion exchange method.Wherein the sulfide coagulation is the most general, because required step and equipment are simpler, and this method operating cost is low.This method comprises makes phosphoric acid and hydrogen sulfide, or is dissolved in the sodium sulphite that can produce hydrogen sulfide in the phosphoric acid, and contacts such as Sodium sulfhydrate make the form precipitation of arsenic with arsenic sulfide, separate subsequently and remove.On the contrary, solvent extration and ion exchange method are not too general, because step and equipment complexity, and cost is higher.
Yet the sulfide coagulation also needs filtration unit, vacuum filter for example, pressure filter, centrifuge separator etc.The arsenic sulfide that precipitates tends to form colloid, causes to be difficult to separate and to be difficult to remove arsenic from phosphoric acid.Comprise process activated carbon tower route method (Japanese kokai publication hei 6-48712 communique) and comprise the method (Japanese kokai publication hei 6-100307 communique) that adds resin for ease of separating, having used.These methods are not preferred method, because equipment and processing cost are higher.
And when residual when hydrogen sulfide is arranged in the phosphoric acid, the corrodibility of phosphoric acid strengthens, thereby need slough excessive hydrogen sulfide with air and nitrogen, causes step complicated.When using, during compounds such as Sodium sulfhydrate, in sodium content very important use, can not use this method, because sodium remains in the phosphoric acid in a large number such as sodium sulphite.
When using the sulfide coagulation, when phosphoric acid concentration was higher, particularly under the Tripyrophosphoric acid situation, phosphoric acid itself reached higher viscosity, separated therefore that to remove arsenic sulfide more difficult.Therefore, this method is applicable to P
2O
5The highest 60% the phosphoric acid that is about of concentration.
The method of dearsenification from high-concentration phosphoric acid, Japanese Patent Publication 53-128595 communique disclose the method for wet technique refinement phosphoric acid.According to this method, to P
2O
5Concentration is up in about 82% the phosphoric acid and adds sodium-chlor, makes arsenic and chlorine reaction in the phosphoric acid to separate and to remove.Because this method comprises the sodium-chlor that uses 1000-2000ppm, remaining in the phosphoric acid after dearsenification have a large amount of sodium.
The general arsenic removing method step of need filtering and outgas, this two step is all costly, and remaining in phosphoric acid a large amount of sodium is arranged.They can not be used for P
2O
5Concentration is not less than in 60% the high-concentration phosphoric acid, particularly in the Tripyrophosphoric acid.In addition, also can't obtain having low arsenic, heavy metal, the high-concentration phosphoric acid of silicon-dioxide and sodium content, particularly Tripyrophosphoric acid by practicable low cost method.Therefore, the Application Areas of Tripyrophosphoric acid do not need to be confined to highly purified field.
The invention provides a kind of method of dearsenification from phosphoric acid completely newly, its operating cost is low, and is different with the sulfide coagulation, and it does not need to filter and degassing step, does not have a large amount of remaining sodium, and this method is applicable to high-concentration phosphoric acid, particularly Tripyrophosphoric acid.Also have, the objective of the invention is to obtain having low arsenic, heavy metal, the high purity polyphosphoric acid of silicon-dioxide and sodium content, it can not obtain with ordinary method.
Disclosure of the Invention
The present inventor has carried out intensive research for addressing the above problem, and finds that in the organic synthesis process of the association hydrogenchloride that carries out in high-concentration phosphoric acid, the arsenic content of phosphoric acid obviously reduces.It further be studies show that, this organic synthesis itself does not matter with the dearsenification effect, but by phosphoric acid is contacted with hydrogen halide, the arsenic content of phosphoric acid can be reduced to and be no more than about 1ppm, also finds, when contact is to be that there be following carrying out in the compound that can form hydrogen halide under the acidic conditions, the dearsenification effect improves, and this method is for dearsenification, and particularly dearsenification is that effectively this is accomplished the present invention from Tripyrophosphoric acid.
Therefore, the invention provides:
(1) method of purification of phosphoric acid, this method comprise makes arsenical phosphoric acid contact with hydrogen halide, dearsenification from phosphoric acid thus.
(2) process for purification of above-mentioned (1) wherein makes arsenical phosphoric acid be that the compound existence that can form hydrogen halide under the acidic conditions contacts with hydrogen halide down.
(3) process for purification of above-mentioned (2) wherein can form the compound of hydrogen halide under acidic conditions, be to add with the ratio that is lower than phosphoric acid weight 1%.
(4) process for purification of above-mentioned (2) wherein can form the compound of hydrogen halide under acidic conditions, be iron (II) muriate of copper (I) or tin (II).
(5) process for purification of above-mentioned (1), wherein hydrogen halide is a hydrogenchloride.
(6) process for purification of above-mentioned (1), wherein phosphoric acid has and is not less than 72.4% P
2O
5Concentration.
(7) highly purified Tripyrophosphoric acid, its iron (Fe) content is no more than 20ppm, and sodium (Na) content is no more than 100ppm, silicon-dioxide (SiO
2) content is no more than 50ppm, and arsenic (As) content is no more than 1ppm.
(8) high purity polyphosphoric acid of above-mentioned (7), wherein iron (Fe) content is no more than 10ppm, and sodium (Na) content is no more than 5ppm, silicon-dioxide (SiO
2) content is no more than 5ppm, and arsenic (As) content is no more than 1ppm.
(9) high purity polyphosphoric acid of above-mentioned (7), its chromium (Cr) content is no more than 5ppm, and nickel (Ni) content is no more than 5ppm, and molybdenum (Mo) content is no more than 5ppm.
(10) high purity polyphosphoric acid of above-mentioned (8), wherein chromium (Cr) content is no more than 2ppm, and nickel (Ni) content is no more than 2ppm, and molybdenum (Mo) content is no more than 2ppm.
Before the present invention is described in detail, as follows to the representation specification of phosphoric acid concentration.
In the present invention, phosphoric acid is ortho-phosphoric polycondensation product, and its concentration transforms back or P with ortho-phosphoric acid usually
2O
5Concentration after the conversion is represented.Ortho-phosphoric acid concentration is 100% phosphoric acid, is equivalent to P
2O
5Concentration is 72.4% phosphoric acid, and wherein the relation between two concentration is represented with following equation:
P
2O
5Concentration (%)=ortho-phosphoric acid concentration (%) * 0.724
P
2O
5Concentration is lower than 72.4% phosphoric acid, is phosphate aqueous solution, contains ortho-phosphoric acid polycondensation product and water under equilibrium state.P
2O
5Concentration is not less than 72.4% phosphoric acid, only is made up of the ortho-phosphoric acid polycondensation product, is called Tripyrophosphoric acid, strong phosphoric acid or super phosphoric acid.In the present invention, phosphoric acid concentration P
2O
5Concentration is represented.
In first embodiment of purification of phosphoric acid method according to the present invention, arsenical phosphoric acid is contacted, dearsenification from phosphoric acid separately with hydrogen halide.Reason that in this way can dearsenification is also uncertain, but changing into the arsenic in the phosphoric acid, the supposition hydrogen halide has high-volatile arsenic compound, for example arsonium halide and arsonium, this compound evaporates under the treatment temp of process for purification of the present invention, and emits with hydrogen halide from system.At present also do not know the chemical state of arsenic in phosphoric acid, but think that arsenic is with arsenic acid, arsenus acid, arsenic powder, forms such as white arsenic exist.
Although there is no particular limitation to being applied to phosphoric acid concentration in first embodiment, when this method was used for lower concentration phosphoric acid, hydrogen halide can be dissolved in the water, had increased the corrodibility of phosphoric acid, and it is residual to cause handling the back hydrogen halide.Therefore, to be used for the phosphoric acid of water-content relatively low (high phosphoric acid concentration) be favourable to this method.Especially, when it was used for complete anhydrous Tripyrophosphoric acid, hydrogen halide can not remain in the Tripyrophosphoric acid, can eliminate corrodibility like this.When the phosphoric acid that uses during as Tripyrophosphoric acid, preferred concentration range is the scope that does not have freezing point, i.e. P
2O
5Concentration is 75-77% or is not less than 80%.Consider operability, P
2O
5The upper limit of concentration is preferably 90%.
In second embodiment of purification of phosphoric acid method of the present invention, be that the compound that can generate hydrogen halide under the acidic conditions exists down, makes arsenical phosphoric acid contact with hydrogen halide, dearsenification from phosphoric acid.In this embodiment, dearsenification efficiently.The compound that can generate hydrogen halide under acidic conditions can be the organic or inorganic compound.Especially, it preferably has the metal halide of reductive action, more preferably iron (II), the halogenide of copper (I) or tin (II), the muriate of these metals most preferably, preferred especially iron (II), or the muriate of tin (II).
When arsenical phosphoric acid under acidic conditions, can generate hydrogen halide compound in the presence of when contacting with hydrogen halide, reason owing to the unknown, promoted the dearsenification effect, but supposition arsenic itself becomes and is easy to reduction and becomes volatile arsenic compound easily, for example arsonium halide and arsonium, it is easy to evaporation under the treatment temp of process for purification of the present invention, because when adding particular significant effect during as the metal halide of reductive agent.
In second embodiment, add the compound that under acidic conditions, can generate hydrogen halide of trace, its consumption preferably is lower than the 1wt% of phosphoric acid weight, more preferably less than 0.5wt%.When using this compound with greater amount, the dearsenification effect in theory can be better.But when this compound was metal halide especially, the impurity of metal was worthless in the metal halide in remaining deriving from.When needs are avoided remaining impurity, maybe when needing highly purified phosphoric acid, during particularly highly purified Tripyrophosphoric acid, first embodiment that wherein arsenical phosphoric acid only contacts with hydrogen halide than second embodiment more preferably.
In first and second embodiment, phosphoric acid contacts in any typical solution-air mixing device with hydrogen halide, and described device can be step or continous way.For example, can use and a kind ofly wherein use batch reactor, and vigorous stirring phosphoric acid and the method that directly blasts hydrogen halide wherein, a kind of static mixer or injector of wherein using, and the method for continuous mixed phosphate and hydrogen halide, and a kind of method that is used in combination above-mentioned two kinds of methods etc.The hydrogen halide of Shi Yonging can be a hydrogenchloride in the present invention, and hydrogen bromide etc. preferably use hydrogenchloride, because it can obtain the easyliest and most economical.
In first and second embodiment, greatly depend on the solution-air mixing efficiency of equipment therefor with respect to the requirement of the hydrogen halide of phosphoric acid, and be difficult to stipulate the scope of this amount.Because it is tervalent or pentavalent that the arsenic in phosphoric acid is considered to, with respect to arsenic content, the hydrogen halide that is not less than 3 molar equivalents at least is considered to essential.Using batch reactor, and vigorous stirring phosphoric acid with directly blast under the simplest method situation of hydrogen halide wherein, for example, hydrogenchloride is blasted the 500ml Tripyrophosphoric acid (P that arsenic content is 50ppm
2O
5Concentration is 85%) in speed, be preferably 1~100ml/min, 10~80ml/min more preferably, the time that blasts preferably is not less than 30min, more preferably is not less than 60min.
In first and second embodiment, treatment temp changes according to the material of concentration of phosphoric acid and reactor, but can be the arbitrary values in about 50~200 ℃ of scopes.Consider the corrodibility of phosphoric acid, wish that treatment temp is no more than 150 ℃ industrial stainless material as reactor etc.For the evaporation of the arsenic compound that promote to generate, wish that treatment temp is at least 50 ℃, more preferably is not less than 100 ℃.There is no particular limitation to pressure, can set arbitrarily, wherein just can reach enough dearsenification effects under normal pressure.
And in first and second embodiment, arsenic compound is emitted from system with hydrogen halide.These compounds preferably water absorb and neutralization, or use sodium hydroxide, and the alkaline aqueous solution of potassium hydroxide etc. absorbs.
According to the method for purification of phosphoric acid of the present invention, can obtain having the phosphoric acid of the low arsenic content that is no more than about 1ppm with simple method.Particularly, when being to generate this method of the following use of compound existence of hydrogen halide under the acidic conditions, can obtain having the phosphoric acid of the low arsenic content that is no more than about 0.1ppm.Because this method does not need the equipment cost of filtration step or degassing step, or uses sodium compound, sodium sulphite for example, Sodium sulfhydrate etc., therefore different with method in common, this method is can be in phosphoric acid remaining a large amount of sodium.Have a low heavy metal by process for purification of the present invention being applied to, in the phosphoric acid of sodium and dioxide-containing silica, can obtain having low arsenic content and low heavy metal, the phosphoric acid of silicon-dioxide and sodium content with what dry method obtained.
The method of purification of phosphoric acid of the present invention does not need conventional filtration step.Therefore, this method is applicable to high-concentration phosphoric acid, particularly Tripyrophosphoric acid.Has a low heavy metal by process for purification of the present invention being applied to what dry method obtained, silicon-dioxide and sodium content, but have in the Tripyrophosphoric acid of high arsenic content, the low arsenic content that has that can't obtain before this can be provided, and low heavy metal, the high purity polyphosphoric acid of silicon-dioxide and sodium content.
Particularly, by process for purification of the present invention is applied to phosphoric anhydride is joined industrial phosphoric acid, and be dissolved in wherein and in the Tripyrophosphoric acid of preparation, can obtain iron (Fe) content and be no more than 20ppm, sodium (Na) content is no more than 100ppm, silicon-dioxide (SiO
2) content is no more than 50ppm, arsenic (As) content is no more than 1ppm, and chromium (Cr) content is no more than 5ppm, and nickel (Ni) content is no more than 5ppm, and molybdenum (Mo) content is no more than the Tripyrophosphoric acid of 5ppm.
By process for purification of the present invention is applied in the Tripyrophosphoric acid, this Tripyrophosphoric acid is by phosphoric anhydride being joined in the phosphoric acid or the phosphoric acid as foodstuff additive as reagent, and be dissolved in wherein and preparation, can obtain iron (Fe) content and be no more than 10ppm, sodium (Na) content is no more than 5ppm, silicon-dioxide (SiO
2) content is no more than 5ppm, arsenic (As) content is no more than 1ppm, and chromium (Cr) content is no more than 2ppm, and nickel (Ni) content is no more than 2ppm, and molybdenum (Mo) content is no more than the Tripyrophosphoric acid of 2ppm.
Adopt following method to measure the content of various elements in the Tripyrophosphoric acid in the present invention.
Measure arsenic according to JIS-K 0102 (1993) method.Because think in the Tripyrophosphoric acid sample, not have organic substance, so omitted disclosed step in JIS with sulfuric acid/nitric acid decomposing organic matter matter.Adopt inductively coupled plasma (ICP) analytical method to come quantitative assay iron, chromium, nickel, molybdenum and silicon-dioxide.By in Tripyrophosphoric acid, adding hydrochloric acid, make the hydrochloric acid soln of 1.2M, prepare the ICP sample solution.Regulate the calibration curve of phosphoric acid solution, make its concentration identical with sample solution.Adopt atomic absorption spectrum quantitative assay sodium.The sample solution of atomic absorption be used for the identical of ICP.Measure P in the Tripyrophosphoric acid by using the titration of 1M sodium hydroxide solution
2O
5Concentration.
The present invention will be described in more detail below with reference to embodiment.The present invention is not limited to these embodiment.
Embodiment 1
The arsenic content that obtains with dry method that is purchased 130 ℃ of heated and stirred is Tripyrophosphoric acid (500ml, the P of 58ppm
2O
5Concentration is 84.9%), insert Glass tubing therebetween, and blast the about 2h of hydrogen chloride gas with the inflation rate of 20ml/min with the bowl-shape strainer of glass, obtain highly purified Tripyrophosphoric acid.In aqueous sodium hydroxide solution, catch the hydrogen chloride gas of emitting.The analytical results of the high purity polyphosphoric acid that obtains is listed in the table 1.
Embodiment 2
With the arsenic content that obtains with dry method that is purchased is Tripyrophosphoric acid (500ml, the P of 8ppm
2O
5Concentration is 84.2%), be injected in 1 liter of three mouthfuls of glass flask, and, insert Glass tubing therebetween, and blast the about 2h of hydrogen chloride gas with the inflation rate of 50ml/min with the bowl-shape strainer of glass 150 ℃ of heated and stirred, obtain highly purified Tripyrophosphoric acid.In aqueous sodium hydroxide solution, catch the hydrogen chloride gas of emitting.The analytical results of the high purity polyphosphoric acid that obtains is listed in the table 1.
Embodiment 3
Be that the phosphoric anhydride (200g) of 25ppm joins as the arsenic content of reagent with arsenic content be phosphoric acid (422g, the P of 0.1ppm
2O
5Concentration is 61.5%) in.This mixture obtains uniform liquid 120 ℃ of heated and stirred, and preparing arsenic content thus is the Tripyrophosphoric acid (P of 8ppm
2O
5Concentration is 84.0%).Under 150 ℃ of heated and stirred situations, insert Glass tubing, and blast the about 3h of hydrogen chloride gas with the inflation rate of 20ml/min with the bowl-shape strainer of glass, obtain highly purified Tripyrophosphoric acid.In aqueous sodium hydroxide solution, catch the hydrogen chloride gas of emitting.The analytical results of the high purity polyphosphoric acid that obtains is listed in the table 1.
Embodiment 4
With arsenic content is the phosphoric anhydride (170g) of 25ppm, and joining the arsenic content that obtains with dry method that is purchased is Tripyrophosphoric acid (330g, the P of 5ppm
2O
5Concentration is 76.0%) in.This mixture obtains uniform liquid 120 ℃ of heated and stirred, and preparing arsenic content thus is the Tripyrophosphoric acid (P of 11ppm
2O
5Concentration is 84.2%).Under 150 ℃ of heated and stirred situations, insert Glass tubing, and blast the about 3h of hydrogen chloride gas with the inflation rate of 20ml/min with the bowl-shape strainer of glass, obtain highly purified Tripyrophosphoric acid.In aqueous sodium hydroxide solution, catch the hydrogen chloride gas of emitting.The analytical results of the high purity polyphosphoric acid that obtains is listed in the table 1.
Embodiment 5
With arsenic content is industrial phosphoric acid (500ml, the P of 15ppm
2O
5Concentration is 65%), be injected in 1 liter of three mouthfuls of glass flask, and, insert Glass tubing therebetween, and blast hydrogen chloride gas with the inflation rate of 50ml/min with the bowl-shape strainer of glass 130 ℃ of heated and stirred.In aqueous sodium hydroxide solution, catch the hydrogen chloride gas of emitting.As a result, began back 180 minutes in air-blowing, the arsenic concentration in the phosphoric acid is 0.8ppm.
Embodiment 6
Use the treatment process identical, just before blasting hydrogen chloride gas, add iron(ic) chloride (II) (0.1g) with embodiment 5.As a result, began back 120 minutes in air-blowing, the arsenic concentration in the phosphoric acid is 0.07ppm.
Embodiment 7
Use the treatment process identical with embodiment 5, just adding two hydration tin chlorides (II) are (0.5g) before blasting hydrogen chloride gas.As a result, began back 120 minutes in air-blowing, the arsenic concentration in the phosphoric acid is 0.08ppm.
The analytical results of the every kind of element that contains in the high purity polyphosphoric acid that obtains in embodiment 1-4 is listed in the table 1.In order to compare, the analytical results of Tripyrophosphoric acid product A that obtains with dry method that is purchased and the Tripyrophosphoric acid product B that obtains with wet method that is purchased is also listed in the table 1.
Table 1
| Analysis project | Embodiment 1 | Embodiment 2 | Embodiment 3 | Embodiment 4 | The product A that is purchased | The product B that is purchased |
| P 2O 5Concentration (%) | 84.9 | 84.2 | 84.0 | 84.2 | 85.0 | 84.3 |
| Fe content | 1.6 | 1.0 | 0.2 | 1.2 | 1.6 | 37 |
| Cr content | 0.8 | 0.1 | 0.1 | 0.7 | 0.8 | 6.3 |
| Ni content | 0.6 | 0.3 | 0.1 | 0.4 | 0.6 | 4.4 |
| Mo content | <0.5 | <0.5 | <0.5 | <0.5 | <0.5 | 12 |
| Na content | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | 250 |
| SiO 2Content | <5 | <5 | <5 | <5 | <5 | 120 |
| As content | 0.5 | 0.08 | 0.03 | 0.03 | 58 | 0.02 |
In table 1, each content unit is ppm.
Can find out obviously that from table 1 product A that is purchased (Tripyrophosphoric acid that obtains with dry method) demonstrates low heavy metal, silicon-dioxide and sodium content, but high arsenic content, and the product B that is purchased (Tripyrophosphoric acid that obtains with wet method) demonstrates low arsenic content, but high heavy metal, sodium and dioxide-containing silica.On the contrary, the high purity polyphosphoric acid of embodiment 1-4 demonstrates low arsenic content and low heavy metal, sodium and dioxide-containing silica.Can obviously find out from embodiment 6 and 7, when arsenical phosphoric acid is can generate under the acidic conditions compound of hydrogen halide, iron(ic) chloride (II) for example, tin chlorides (II) etc. exist down, contact with hydrogen halide, can improve the effect that removes the arsenic in the phosphoric acid.
Can find out obviously that from above-mentioned explanation adopt the simple operation that phosphoric acid is contacted with hydrogen halide, the method for purification of phosphoric acid of the present invention can remove arsenic harmful in the phosphoric acid effectively.Particularly, the arsenic content of tens ppm of general industrial phosphoric acid can drop to and be no more than about 1ppm.When being to generate the following use of the compound existence above-mentioned steps of hydrogen halide under the acidic conditions, can reach the level that removes that is no more than about 0.1ppm.
Described method comprises simple treatment step, and does not need special device.As a result, the total cost of processing is lower, and different with the method for routine, owing to do not use sodium compound, and can abundant residues sodium in phosphoric acid.
And different with the process for purification of routine, because the method for purification of phosphoric acid of the present invention does not need filtration step, it can be used for high-concentration phosphoric acid, particularly in the Tripyrophosphoric acid.Especially, to obtain with dry method, and has a low heavy metal, sodium and dioxide-containing silica, but the Tripyrophosphoric acid of high arsenic content is refining with method of the present invention, can obtain having low arsenic content and low heavy metal, the high purity polyphosphoric acid of silicon-dioxide and sodium content, this can't obtain before being.This high purity polyphosphoric acid is a high safety, and can alleviate the load of environment.Therefore, can be at food, use widely in fields such as medicine and electronic material.
The application is based on the patent application Nos.373696/1998 and 230628/1999 that submits in Japan, and its content is incorporated herein by reference.
Claims (6)
1. the method for a purification of phosphoric acid comprises hydrogen halide is blasted in the arsenical phosphoric acid, and wherein, with respect to arsenic content, the amount of blasting of hydrogen halide is not less than 3 molar equivalents, dearsenification from phosphoric acid thus.
2. the process of claim 1 wherein that described hydrogen halide is to blast in the presence of the compound that forms hydrogen halide under the acidic conditions.
3. the method for claim 2, the wherein said content that can form the compound of hydrogen halide under acidic conditions is lower than the 1wt% of phosphoric acid weight.
4. claim 2 or 3 method, the wherein said compound that can form hydrogen halide under acidic conditions is iron (II), the muriate of copper (I) or tin (II).
5. each method among the claim 1-3, wherein said hydrogen halide is a hydrogenchloride.
6. each method among the claim 1-3, the P of wherein said phosphoric acid
2O
5Concentration is not less than 72.4%.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP37369698 | 1998-12-28 | ||
| JP1998373696 | 1998-12-28 | ||
| JP1999230628 | 1999-08-17 |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB998151521A Division CN1321058C (en) | 1998-12-28 | 1999-12-24 | Method for refining phosphoric acid and high-purity polyphosphoric acid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1817790A CN1817790A (en) | 2006-08-16 |
| CN100339299C true CN100339299C (en) | 2007-09-26 |
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ID=27742360
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005101136508A Expired - Fee Related CN100339299C (en) | 1998-12-28 | 1999-12-24 | Method for purification of phosphoric acid |
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|---|---|
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|---|---|---|---|---|
| CN111217345A (en) * | 2020-02-28 | 2020-06-02 | 成都易态科技有限公司 | Yellow phosphorus furnace gas preparation device, yellow phosphorus condensation system and yellow phosphorus furnace gas preparation method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4044108A (en) * | 1976-02-13 | 1977-08-23 | Toyo Soda Manufacturing Co., Ltd. | Process for removing organic material from wet process phosphoric acid |
| US5246681A (en) * | 1991-10-11 | 1993-09-21 | Enichem Agricoltura S.P.A. | Process for the removal of cadmium from solutions of phosphoric acid |
-
1999
- 1999-12-24 CN CNB2005101136508A patent/CN100339299C/en not_active Expired - Fee Related
-
2001
- 2001-07-27 ZA ZA200106211A patent/ZA200106211B/en unknown
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4044108A (en) * | 1976-02-13 | 1977-08-23 | Toyo Soda Manufacturing Co., Ltd. | Process for removing organic material from wet process phosphoric acid |
| US5246681A (en) * | 1991-10-11 | 1993-09-21 | Enichem Agricoltura S.P.A. | Process for the removal of cadmium from solutions of phosphoric acid |
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|---|---|
| ZA200106211B (en) | 2002-07-29 |
| CN1817790A (en) | 2006-08-16 |
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