CN102127639A - Preparation method of high-clarity uranium solution - Google Patents
Preparation method of high-clarity uranium solution Download PDFInfo
- Publication number
- CN102127639A CN102127639A CN2010106034111A CN201010603411A CN102127639A CN 102127639 A CN102127639 A CN 102127639A CN 2010106034111 A CN2010106034111 A CN 2010106034111A CN 201010603411 A CN201010603411 A CN 201010603411A CN 102127639 A CN102127639 A CN 102127639A
- Authority
- CN
- China
- Prior art keywords
- uranium
- solution
- diuranate
- preparation
- diatomite
- 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
Images
Abstract
The invention provides a preparation method of a high-clarity uranium solution, comprising the following steps of: (1) dissolving diuranate solid in a nitric acid solution until the diuranate solid is completely dissolved to finish acid dissolution; (2) within 0-24 hours after acid dissolution, under the condition of stirring, adding 1-50kg of kieselguhr per cubic meter of the uranium dissolving solution obtained in the step (1), reacting for 0.5-1 hour; and (3) within 0-5 hours after the step (2), filtering the uranium dissolving solution by a plate and frame filter press to obtain a uranyl nitrate solution with the solid concentration of less than 50mg/L, wherein a layer of kieselguhr is pre-coated on the filter cloth of the plate and frame filter press, the coating thickness of the kieselguhr is 1-2mm, and the filtration pressure is 0.2-0.6MPa. The preparation method provided by the invention acquires a high-clarity extraction stock solution by an economical means, and meets the requirements of the subsequent extraction process on the quality of the extraction stock solution.
Description
Technical field
The present invention relates to the solid-liquid separation technique in nuclear chemical industry field, be specifically related to a kind of preparation method of good clarity uranium solution.
Background technology
In the nuclear fuel cycle process, prepare the treating process that a series of chemical processes of examining level or nuclear power level product are called uranium from thick uranium concentrate (yellow cake).The refining refining and wet technique refinement of dry method that is divided into of uranium, in the wet technique refinement process of uranium, mainly comprise several operations such as solid-liquid separation, extracting and separating, precipitated crystal, drying and calcining, extracting and separating is the core of uranium refinement flow process, and what how to reduce emulsion in the extraction process is the emphasis that extraction process is studied for many years.
The preparation of uranium refinement flow process collection stoste is be raw material with uranium concentrate (yellow cake), adopts nitric acid dissolve, obtains the uranium lysate, adopts the solid matter that filters in the operation removal lysate to obtain clarifying uranium solution again.Because the main component of homemade uranium concentrate (yellow cake) is sodium diuranate or ammonium diuranate, it contains a large amount of silicon and nitric acid insolubles impurity, how to exist with aerosol form.Adopt common filter method, then very fast meeting forms the filtering layer of one deck densification on filtration medium surface, cause filtration velocity very slow, and flocks appears in gained filtrate postpone of a specified duration meeting, very likely causes follow-up extraction process emulsive to take place.Discover that these suspended matters are that silicon and other molecule of different polymerization states formed, and adopt common filter method, then can form the filtering layer of one deck densification very soon, filtration velocity is very slow, and flocks appears in filtrate postpone of a specified duration meeting, very likely causes the emulsification of follow-up extraction process.Industrial for preventing the gathering of silicon in the lysate, the one, adopt 700～800 ℃ with the uranium concentrate calcining method so that the modification of indefinite form silicon becomes typing silicon, thereby avoid the clustering phenomena of silicon in lysate, improve the clarity of filtration velocity and filtrate.Or adopt the long-term standing methods of uranium lysate, the silicon in the solution is assembled, the form sedimentation with suspended substance can add flocculation agent therebetween, relies on the gathering of the throwing out quickening silicon of flocculation agent, makes floc sedimentation dimension lengthening, increases settling velocity.And then respectively supernatant liquor and underflow are filtered respectively, filtrate is the clarification uranium solution, as collection stoste, filter residue returns the mine and leaches.
Aforesaid method exists following deficiency:
Adopting drying, calcining method makes indefinite form silicon modification in the uranium concentrate, and then adopt the nitric acid dissolve calcinate to prepare in the method for clarification uranium solution (collection stoste), though the filtration velocity of lysate is very fast, collection stoste clarity is also higher, but uranium concentrate is through 700～800 ℃ of high-temperature calcinations, uranium not only per ton will increase by 2500 yuan of calcining expenses, and owing to also contain other impurity in the uranium concentrate, the loose particles degree is relatively poor, there is sintering phenomenon in the part particle, the sodium diuranate of this part sinter meeting wrapping portion, be difficult to be dissolved when nitric acid dissolve, cause that uranium content is 1～2% in the filter residue, uranium loses bigger in filter residue.
In to lysate in the method for suspended substance elder generation sedimentation after-filtration, though saved the incinerating energy consumption, but lysate is through long-time (＞leaving standstill 48h), bottom in the solution has suspended substance to assemble, and adopts dense method still can not reach effective separation of solid-liquid to this underflow materials, still need adopt plate-and-frame filter press to separate, not only filtering velocity is slow, filter residue is moisture higher, operation such as is difficult to wash, and uranium loses bigger in filter residue; Though top solution suspended substance greatly reduces, but still contains the part suspended substance, moreover particle is more tiny, compare with underflow materials, filtration velocity is not seen obvious lifting, also filtrate postpone of a specified duration still have suspended substance to occur, be difficult to reach the demand of follow-up extraction process to the quality of collection stoste.
Summary of the invention
The object of the present invention is to provide a kind of preparation method of good clarity uranium solution, it has obtained good clarity collection stoste (filtrate solids concn＜50mg/L), satisfy the quality requirement of follow-up extraction process, solved in the existing collection stoste technology of preparing existing or energy consumption is high, it is low or filtration velocity slow, filtrate clarity is low, filter the low problem of yield to filter yield collection stoste
Realize the technical scheme of the object of the invention: a kind of preparation method of good clarity uranium solution, it comprises the steps:
(1) adopt salpeter solution that the diuranate solid is dissolved, until the dissolving of diuranate solid fully, sour cementing bundle;
(2) in the sour cementing bundle of step (1) 0～24 hour, adding diatomite under the agitation condition in the uranium lysate of step (1) gained, the diatomite add-on is every cubic metre of lysate 1～50kg, reacts end in 0.5～1 hour;
(3) finish in 0～5 hour in step (2) then, adopt plate-and-frame filter press to filter the uranium lysate, obtain uranyl nitrate solution, solids concn＜50mg/L in this solution; Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 1～2mm, filter pressure 0.2～0.6Mpa.
The preparation method of aforesaid a kind of good clarity uranium solution, its described diuranate is sodium diuranate, ammonium diuranate, heavy uranic acid magnesium or heavy uranic acid calcium.
The preparation method of aforesaid a kind of good clarity uranium solution, the solvent temperature of its step (1) is 50～100 ℃.
The preparation method of aforesaid a kind of good clarity uranium solution, the used concentration of nitric acid mass percent of its step (1) is 40～98%.
Effect of the present invention is:
The present invention proposes a kind of preparation method of good clarity uranium solution, this technology adopts the means of less expensive, obtained good clarity collection stoste (filtrate solids concn＜50mg/L), satisfied the quality requirement of follow-up extraction process, solved in the existing collection stoste technology of preparing existing or energy consumption is high, it is low or filtration velocity slow, filtrate clarity is low, filter the low problem of yield to filter yield collection stoste.
The present invention adds diatomite in the uranium lysate, by diatomite being added the grasp on opportunity, promptly in the uranium lysate, add diatomite with interior, and filtered the uranium lysate with interior employing plate-and-frame filter press, can prevent the α-SiO in the lysate at 5 hours sour cementing bundle 24 hours
2And β-SiO
2Assemble and form γ-SiO
2, avoid cotton-shaped γ-SiO
2To the obstruction that filter opening forms, the micropore that utilizes diatomite formation again is with β-SiO
2Remove, obtain the uranium-bearing filtrate of stable good clarity.The present invention applies one deck diatomite in advance on the filter cloth of plate-and-frame filter press, reduce the filter of wearing of molecule, avoids filter cloth to stop up.
The present invention is flocculating aids and precoating paint with diatomite, by diatomite being added the optimization of condition, solved of the interference of the silicic acid of different states effectively to filter operation, when obtaining higher filtering velocity, removed effectively the bigger γ-SiO2 of extraction process influence, the filtrate solids concn is less than 50mg/L, and filtrate postpone of a specified duration does not have flocculent substance to produce yet, and has obtained the filtered liquid of good clarity.With this filtrate is collection stoste, can effectively reduce the emulsion that occurs on tower and the slot type equipment, can reduce the wash number of follow-up extraction step greatly.
Description of drawings
Fig. 1 is preparation method's process flow sheet of a kind of good clarity uranium solution of the present invention.
Embodiment
Preparation method to a kind of good clarity uranium solution of the present invention is further described below in conjunction with the drawings and specific embodiments.
Embodiment 1
As shown in Figure 1, adopt the inventive method to obtain the good clarity uranium solution:
(1) under 75 ℃, adopt salpeter solution that sodium diuranate is dissolved, the concentration of nitric acid mass percent is 63%, and is complete until the dissolving of sodium diuranate solid, sour cementing bundle;
(2) the sour cementing bundle of step (1) 0.5 hour, add diatomite in the uranium lysate of step (1) gained under agitation condition, the diatomite add-on is every cubic metre of lysate 20kg; React end in 0.5 hour;
(3) finished 0.5 hour in step (2) then, adopt plate-and-frame filter press to filter the uranium lysate, obtain uranyl nitrate solution, uranium concentration is 287g/L, solids concn＜50mg/L in the solution.Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 1.5mm, filter pressure 0.4Mpa.Filter residue uranium content 0.027%.
Compare with precoating paint with not adding super-cell, adopt the inventive method filtering velocity to promote obviously, filtrate clarity obviously improves, filtrate solids concn＜50mg/L.
The method for preparing the stoste of coming together with the calcining uranium concentrate is compared, and adopts the inventive method tailings uranium content to drop to 0.03% by 2%, filters yield and is improved.
Embodiment 2
As shown in Figure 1, adopt the inventive method to obtain the good clarity uranium solution:
(1) under 50 ℃, adopt salpeter solution that ammonium diuranate is dissolved; The concentration of nitric acid mass percent is 40%, and is complete until the dissolving of diuranate solid, sour cementing bundle;
(2) the sour cementing bundle of step (1) 24 hours, add diatomite in the uranium lysate of step (1) gained under agitation condition, the diatomite add-on is every cubic metre of lysate 1g; React end in 0.5 hour.
(3) finished 5 hours in step (2) then, adopt plate-and-frame filter press to filter the uranium lysate, obtain uranyl nitrate solution, uranium concentration is 255g/L, solids concn＜50mg/L in the solution.Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 1mm, filter pressure 0.2Mpa.Filter residue uranium content 0.045%.
Embodiment 3
As shown in Figure 1, adopt the inventive method to obtain the good clarity uranium solution:
(1) under 100 ℃, adopt salpeter solution that sodium diuranate is dissolved; The concentration of nitric acid mass percent is 98%, and is complete until the dissolving of sodium diuranate solid, sour cementing bundle;
(2) the sour cementing bundle of step (1) 10 hours, add diatomite in the uranium lysate of step (1) gained under agitation condition, the diatomite add-on is every cubic metre of lysate 50kg; React end in 1 hour.
(3) finished 3 hours in step (2) then, adopt plate-and-frame filter press to filter the uranium lysate, obtain uranyl nitrate solution, uranium concentration is 315g/L, solids concn＜50mg/L in the solution.Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 2mm, filter pressure 0.6Mpa.Filter residue uranium content 0.035%.
Embodiment 4
As shown in Figure 1, adopt the inventive method to obtain the good clarity uranium solution:
(1) under 85 ℃, adopt salpeter solution that sodium diuranate is dissolved; The concentration of nitric acid mass percent is 63%, and is complete until the dissolving of sodium diuranate solid, sour cementing bundle;
(2) adding diatomite under the agitation condition in the uranium lysate of step (1) gained immediately at the sour cementing bundle of step (1), the diatomite add-on is every cubic metre of lysate 10kg; React end in 45 minutes.
(3) finish in step (2) then and adopt plate-and-frame filter press to filter the uranium lysate immediately, obtain uranyl nitrate solution, uranium concentration is 306g/L, solids concn＜50mg/L in the solution.Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 1.5mm, filter pressure 0.45Mpa.Filter residue uranium content 0.025%.
Studies show that the polymerization state of silicic acid in solution is different, be divided into α, β, three kinds of forms of γ, α-SiO by the big I of extent of polymerization
2Be the silicic acid of oligomeric form, β-SiO
2For in poly-silicic acid, the high poly-silicic acid of γ-SiO2.Under certain condition, the prolongation that the polymerization state of solution mesosilicic acid can be in time and aggravating, and cause γ-SiO in the solution
2Concentration increase.Because γ-SiO
2Be to be that the colloidal particle of 4～18nm are assembled and to be formed by diameter, it is to cause extraction process to produce the arch-criminal of emulsion, should reduce γ-SiO in the filtrate as far as possible
2Concentration; β-SiO
2Though the not directly influence of generation to emulsion in the extraction process process can slowly be gathered into γ-SiO
2, and quicken the generation of emulsion in the extraction process; α-SiO
2Particle diameter is less, easily passes filtering layer, enters filtrate, and is not only less to the clarity influence of solution, and the generation of emulsion in the extraction process there is not influence yet.
In the lysate of nitric acid dissolve uranium concentrate gained, following reaction takes place in the silicon in the solution:
Na
2SiO
3+2HNO
3＝NaNO
3+SiO
2H
2O
The new silicic acid that produces is mainly with α-SiO
2And β-SiO
2Form exists, if do not add the diatomite direct filtration this moment, because the filter cloth filter opening is bigger, and linear less β-SiO
2And α-SiO
2Filter be can wear and filtrate, filtrate postpone of a specified duration, the β-SiO in the solution entered
2Still can aggregate into γ-SiO
2, form outward appearance visible floss, the clarity of filtrate is reduced, carry out extracting operation with this solution, emulsion very likely takes place.As lysate being put for a long time β-SiO
2Can aggregate into γ-SiO
2, in lysate, have a large amount of flocculent substances and occur, when filtering, can stop up the filter opening of filter cloth, form very fine and close filtering layer, filtration velocity is slower, is difficult in industrial enforcement.
Diatomite mainly is made of silicon-dioxide, obtains in diatom remains settled layer, and its granulometric composition has several different types biologically, every type all has different shapes, some is flaky, and some is a column, contains elliposoidal, fibrous type and acicular.Particle itself is owing to its skeleton structure that has and very high internal penetration is arranged.After by uranium concentrate acid cementing bundle, in lysate, add diatomite immediately and filter, the β-SiO in this moment lysate
2Also do not form the higher γ-SiO of the polymerization degree
2, be difficult to form fine and close filtering layer, although β-SiO
2The polymerization degree is medium, reaches the removal purpose but still can be held back by the filter opening that diatomite forms.
Claims (4)
1. the preparation method of a good clarity uranium solution, it is characterized in that: this method comprises the steps:
(1) adopt salpeter solution that the diuranate solid is dissolved, until the dissolving of diuranate solid fully, sour cementing bundle;
(2) in the sour cementing bundle of step (1) 0～24 hour, adding diatomite under the agitation condition in the uranium lysate of step (1) gained, the diatomite add-on is every cubic metre of lysate 1～50kg, reacts end in 0.5～1 hour;
(3) finish in 0～5 hour in step (2) then, adopt plate-and-frame filter press to filter the uranium lysate, obtain uranyl nitrate solution, solids concn＜50mg/L in this solution; Wherein, apply one deck diatomite on the filter cloth of plate-and-frame filter press in advance, the diatomite coat-thickness is at 1～2mm, filter pressure 0.2～0.6Mpa.
2. the preparation method of a kind of good clarity uranium solution according to claim 1 is characterized in that: described diuranate is sodium diuranate, ammonium diuranate, heavy uranic acid magnesium or heavy uranic acid calcium.
3. the preparation method of a kind of good clarity uranium solution according to claim 1 is characterized in that: the solvent temperature of step (1) is 50～100 ℃.
4. the preparation method of a kind of good clarity uranium solution according to claim 1 is characterized in that: the used concentration of nitric acid mass percent of step (1) is 40～98%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010106034111A CN102127639A (en) | 2010-12-23 | 2010-12-23 | Preparation method of high-clarity uranium solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010106034111A CN102127639A (en) | 2010-12-23 | 2010-12-23 | Preparation method of high-clarity uranium solution |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102127639A true CN102127639A (en) | 2011-07-20 |
Family
ID=44265908
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010106034111A Pending CN102127639A (en) | 2010-12-23 | 2010-12-23 | Preparation method of high-clarity uranium solution |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102127639A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103351064A (en) * | 2013-07-24 | 2013-10-16 | 宜宾海丝特纤维有限责任公司 | Millipore filtration pretreatment technology for recovery of electrodialysis alkali from pressed liquor in production of viscose fiber |
| CN103601245A (en) * | 2013-11-28 | 2014-02-26 | 中核二七二铀业有限责任公司 | Preparation method of diuranate non-metallic element standard substances |
| CN105969987A (en) * | 2016-06-16 | 2016-09-28 | 南华大学 | Method for leaching uranium in radioactive alkali residues |
| CN106636692A (en) * | 2016-12-28 | 2017-05-10 | 中核四0四有限公司 | Uranium purification method for ammonium biuranate |
| CN108441631A (en) * | 2018-01-24 | 2018-08-24 | 中国原子能科学研究院 | The recovery method of uranium in ammonium diuranate mother liquor of precipitation of ammonium |
| CN112680607A (en) * | 2020-12-16 | 2021-04-20 | 核工业北京化工冶金研究院 | High-clarity crystallization back extraction method in uranium extraction process |
| CN114686681A (en) * | 2020-12-30 | 2022-07-01 | 中核通辽铀业有限责任公司 | Remote uranium deposit resource recovery system and method |
| CN115430202A (en) * | 2022-09-06 | 2022-12-06 | 苏州贝林微纤科技有限公司 | Large-bulk density paper fiber filter aid and preparation method and application thereof |
-
2010
- 2010-12-23 CN CN2010106034111A patent/CN102127639A/en active Pending
Non-Patent Citations (3)
| Title |
|---|
| 《中国工程科学》 20081231 阙为民等 "中国铀矿采冶技术发展与展望" 第44-53页 1-4 第10卷, 第3期 * |
| 《铀矿冶》 19891231 刘明德 "硅藻土的助滤性能" 第60-64页 1-4 , 第3期 * |
| 《铀矿冶》 19980228 黄伦光等 "国内外铀纯化工艺状况" 第31-42页 1-4 第17卷, 第1期 * |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103351064A (en) * | 2013-07-24 | 2013-10-16 | 宜宾海丝特纤维有限责任公司 | Millipore filtration pretreatment technology for recovery of electrodialysis alkali from pressed liquor in production of viscose fiber |
| CN103601245A (en) * | 2013-11-28 | 2014-02-26 | 中核二七二铀业有限责任公司 | Preparation method of diuranate non-metallic element standard substances |
| CN103601245B (en) * | 2013-11-28 | 2016-03-02 | 中核二七二铀业有限责任公司 | Diuranate non-metallic element reference material preparation method |
| CN105969987A (en) * | 2016-06-16 | 2016-09-28 | 南华大学 | Method for leaching uranium in radioactive alkali residues |
| CN105969987B (en) * | 2016-06-16 | 2018-01-09 | 南华大学 | The leaching method of uranium in radioactivity alkaline residue |
| CN106636692B (en) * | 2016-12-28 | 2018-11-30 | 中核四0四有限公司 | A kind of uranium purification process of ammonium diuranate |
| CN106636692A (en) * | 2016-12-28 | 2017-05-10 | 中核四0四有限公司 | Uranium purification method for ammonium biuranate |
| CN108441631A (en) * | 2018-01-24 | 2018-08-24 | 中国原子能科学研究院 | The recovery method of uranium in ammonium diuranate mother liquor of precipitation of ammonium |
| CN112680607A (en) * | 2020-12-16 | 2021-04-20 | 核工业北京化工冶金研究院 | High-clarity crystallization back extraction method in uranium extraction process |
| CN114686681A (en) * | 2020-12-30 | 2022-07-01 | 中核通辽铀业有限责任公司 | Remote uranium deposit resource recovery system and method |
| CN114686681B (en) * | 2020-12-30 | 2023-10-20 | 中核通辽铀业有限责任公司 | Remote uranium deposit resource recovery system and method |
| CN115430202A (en) * | 2022-09-06 | 2022-12-06 | 苏州贝林微纤科技有限公司 | Large-bulk density paper fiber filter aid and preparation method and application thereof |
| CN115430202B (en) * | 2022-09-06 | 2023-10-27 | 苏州贝林微纤科技有限公司 | Large bulk density paper fiber filter aid and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102127639A (en) | Preparation method of high-clarity uranium solution | |
| CN101792187B (en) | Method for producing feed grade ferrous sulfate monohydrate from titanium pigment waste acid condensed slag | |
| CN101597688A (en) | From phosphogypsum, reclaim a kind of method of rare earth | |
| CN101886175B (en) | Method for producing diuranate by extracting uranium from rare earth slag containing uranium | |
| CN101288857B (en) | Sepiolite purification technique | |
| CN101284668A (en) | Process for abstracting earth silicon, oxide of alumina and gallium oxide from high-alumina flying ash | |
| WO2013017000A1 (en) | Pretreatment method in titanium white preparation by recycling acid hydrolysis residue | |
| CN102757078B (en) | Method for separating useful components from bayer process red mud | |
| CN103145161A (en) | Method for preparing pseudo-boehmite co-preparation white carbon black by coal gangue | |
| CN102101699A (en) | Method for extracting pyrolusite and producing manganese sulfate by utilizing by-product in production of titanium white | |
| CN102910676A (en) | Preparation method of high-purity vanadium pentoxide | |
| CN105016371A (en) | Preparation method of electronic grade ceric sulfate | |
| CN101570551A (en) | Additive used for intensified extraction of humic acid from brown coal and application method thereof | |
| CN102849764B (en) | Method for preparing pseudo-boehmite by pulverized fuel ash | |
| CN106395775A (en) | Method for filtering phosphoric acid extraction slurry | |
| CN103436716B (en) | Method for extracting vanadium from vanadium-containing clinker aggregate | |
| CN103233119B (en) | Process for producing manganese sulfate by treating two ores with acid | |
| CN101597687A (en) | The sulfuric acid rare earth that goes out from the phosphogypsum leaching solution crystallization is converted into the method for rare earth chloride | |
| CN108394931B (en) | Method for preparing 3BS (3-beta-butyl benzene) by utilizing acid leaching lead mud | |
| CN103602837B (en) | Method for collecting scandium oxide from anatase associated scandium mineral | |
| CN1315723C (en) | Method for preparing high-purity ultrnfine silicone powder and aluminium sulphate using kadin as raw material | |
| CN1036775C (en) | Method for production of high-content ferric oxide red colorant from iron-contained industrial burned dregs | |
| CN103332699B (en) | A kind of sodium silicate deferrization method | |
| CN111689509B (en) | Device and method for preparing micro-powder calcium carbonate by using carbide slag | |
| CN101985100B (en) | Filter aid for filtering tailings obtained by carrying out reverse flotation on phosphate ores and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20110720 |