CN114293012B - Method for reducing iron and aluminum content in rare earth sulfate leaching solution - Google Patents
Method for reducing iron and aluminum content in rare earth sulfate leaching solution Download PDFInfo
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- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 157
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims abstract description 120
- -1 rare earth sulfate Chemical class 0.000 title claims abstract description 110
- 238000002386 leaching Methods 0.000 title claims abstract description 98
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 62
- 238000000034 method Methods 0.000 title claims abstract description 56
- 229910052742 iron Inorganic materials 0.000 title claims abstract description 40
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 39
- 239000000243 solution Substances 0.000 claims abstract description 111
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 70
- 239000000395 magnesium oxide Substances 0.000 claims abstract description 59
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims abstract description 48
- 239000011259 mixed solution Substances 0.000 claims abstract description 42
- 239000002002 slurry Substances 0.000 claims abstract description 35
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims abstract description 29
- 235000011941 Tilia x europaea Nutrition 0.000 claims abstract description 29
- 239000004571 lime Substances 0.000 claims abstract description 29
- 239000008267 milk Substances 0.000 claims abstract description 29
- 210000004080 milk Anatomy 0.000 claims abstract description 29
- 235000013336 milk Nutrition 0.000 claims abstract description 29
- 239000007788 liquid Substances 0.000 claims abstract description 28
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims abstract description 15
- 238000000926 separation method Methods 0.000 claims abstract description 14
- 150000002910 rare earth metals Chemical class 0.000 claims description 50
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 30
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 22
- 239000012141 concentrate Substances 0.000 claims description 11
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 10
- 238000002156 mixing Methods 0.000 claims description 10
- 238000001914 filtration Methods 0.000 claims description 8
- 239000000292 calcium oxide Substances 0.000 claims description 5
- 235000012255 calcium oxide Nutrition 0.000 claims description 5
- 239000011706 ferric diphosphate Substances 0.000 claims description 5
- 235000007144 ferric diphosphate Nutrition 0.000 claims description 5
- CADNYOZXMIKYPR-UHFFFAOYSA-B ferric pyrophosphate Chemical compound [Fe+3].[Fe+3].[Fe+3].[Fe+3].[O-]P([O-])(=O)OP([O-])([O-])=O.[O-]P([O-])(=O)OP([O-])([O-])=O.[O-]P([O-])(=O)OP([O-])([O-])=O CADNYOZXMIKYPR-UHFFFAOYSA-B 0.000 claims description 5
- 229940036404 ferric pyrophosphate Drugs 0.000 claims description 5
- 229910021653 sulphate ion Inorganic materials 0.000 claims description 4
- 239000012535 impurity Substances 0.000 abstract description 24
- 230000003472 neutralizing effect Effects 0.000 abstract description 8
- 239000002893 slag Substances 0.000 description 24
- 238000006386 neutralization reaction Methods 0.000 description 21
- 238000006243 chemical reaction Methods 0.000 description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 230000000052 comparative effect Effects 0.000 description 9
- 238000005406 washing Methods 0.000 description 8
- 239000002253 acid Substances 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 4
- 238000009776 industrial production Methods 0.000 description 4
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 3
- 235000011114 ammonium hydroxide Nutrition 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 230000008025 crystallization Effects 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 241000242583 Scyphozoa Species 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- 238000001479 atomic absorption spectroscopy Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 229910001385 heavy metal Inorganic materials 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 239000012452 mother liquor Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000001502 supplementing effect Effects 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- ZSLUVFAKFWKJRC-IGMARMGPSA-N 232Th Chemical compound [232Th] ZSLUVFAKFWKJRC-IGMARMGPSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 229910052776 Thorium Inorganic materials 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- JYYOBHFYCIDXHH-UHFFFAOYSA-N carbonic acid;hydrate Chemical compound O.OC(O)=O JYYOBHFYCIDXHH-UHFFFAOYSA-N 0.000 description 1
- IKNAJTLCCWPIQD-UHFFFAOYSA-K cerium(3+);lanthanum(3+);neodymium(3+);oxygen(2-);phosphate Chemical compound [O-2].[La+3].[Ce+3].[Nd+3].[O-]P([O-])([O-])=O IKNAJTLCCWPIQD-UHFFFAOYSA-K 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910000514 dolomite Inorganic materials 0.000 description 1
- 239000010459 dolomite Substances 0.000 description 1
- QWDJLDTYWNBUKE-UHFFFAOYSA-L magnesium bicarbonate Chemical compound [Mg+2].OC([O-])=O.OC([O-])=O QWDJLDTYWNBUKE-UHFFFAOYSA-L 0.000 description 1
- 239000002370 magnesium bicarbonate Substances 0.000 description 1
- 229910000022 magnesium bicarbonate Inorganic materials 0.000 description 1
- 235000014824 magnesium bicarbonate Nutrition 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 235000014380 magnesium carbonate Nutrition 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052590 monazite Inorganic materials 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000000941 radioactive substance Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 239000008399 tap water Substances 0.000 description 1
- 235000020679 tap water Nutrition 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
Classifications
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention discloses a method for reducing the content of iron and aluminum in rare earth sulfate leaching liquid, which comprises the following steps: (1) Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element according to the flow rate of 0.6-2.7L/min to obtain a first mixed solution with the pH value of 3.1-3.6; (2) Introducing the magnesia slurry into the first mixed solution according to the flow rate of 0.5-3.0L/min to obtain a second mixed solution with the pH value of 5.3-5.5; (3) Reacting the second mixed solution for 1-3 h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution; wherein, fe is used in the rare earth sulfate solution 2 O 3 The content of iron element is less than 0.0015wt% calculated as Al 2 O 3 The content of the aluminum element is less than 0.01wt%. Compared with the traditional method for neutralizing and removing impurities from the rare earth sulfate leaching solution by only using magnesium oxide, the method provided by the invention can further reduce the content of iron and aluminum in the rare earth sulfate leaching solution.
Description
Technical Field
The invention relates to a method for reducing iron and aluminum content in rare earth sulfate leaching solution.
Background
In the rare earth wet smelting process, concentrated sulfuric acid and a small amount of iron powder are added into rare earth concentrate to be roasted at high temperature to generate rare earth roasted ore, tap water is added to be soaked in water, upper plate frame filtration is carried out to generate rare earth sulfate leaching solution, then neutralization and impurity removal are carried out on the rare earth sulfate leaching solution, magnesium oxide is generally adopted to remove impurities such as iron and aluminum in the rare earth sulfate leaching solution during neutralization and impurity removal, and however, the iron and aluminum content in a sulfuric acid rare earth solution obtained after neutralization and impurity removal by magnesium oxide still needs to be further reduced. In addition, the residual magnesium oxide content in the rare earth sulfate solution obtained after neutralization and impurity removal by using magnesium oxide is high, and cannot meet the industrial production standard.
Other neutralizing agents are used to replace magnesium oxide for neutralization and impurity removal. For example, CN113373326a discloses a method for preparing pure rare earth sulfate solution, which comprises (1) leaching a roasted ore obtained by roasting rare earth concentrate with sulfuric acid for one time to obtain supersaturated rare earth sulfate solution and primary leaching slag; (2) Crystallizing the supersaturated sulfuric acid rare earth solution obtained by primary leaching to obtain pure sulfuric acid rare earth crystals and crystallization mother liquor; (3) Carrying out secondary leaching and impurity removal on the crystallization mother liquor obtained by crystallization and leaching slag obtained by primary leaching after supplementing water or magnesium bicarbonate solution to obtain secondary leaching liquid and secondary leaching slag; (4) And (3) dissolving the pure rare earth sulfate crystals obtained in the step (2) by adopting the leaching solution obtained by the secondary leaching to obtain a rare earth sulfate solution. The patent document does not mention the aluminum content in the rare earth sulfate solution, and the steps of the patent document are relatively complicated. CN1721559a discloses a method for comprehensively recovering rare earth and thorium from rare earth ore, mixing mixed rare earth concentrate or monazite ore with concentrated sulfuric acid and iron-containing auxiliary agent, and roasting under proper conditions; leaching the roasted ore with water or dilute acid, and directly filtering to obtain low-radioactivity slag and water leaching solution; neutralizing the water leaching solution, and filtering to obtain rare earth sulfate solution. The leaching solution is neutralized to pH 3.5-5 with one or two of magnesium oxide, magnesite, dolomite, magnesia, and hydromagnesia. The patent document does not mention the aluminum content in the resulting rare earth sulfate solution.
In addition, CN104328290B discloses an ionic rare earth concentrate acid leaching process, comprising: carrying out primary acid leaching on the ionic rare earth concentrate, controlling the pH value of a reaction system to be 2-3, and obtaining primary slag and primary leaching liquid through solid-liquid separation; performing secondary acid leaching on the primary slag, controlling the pH value of a reaction system to be less than or equal to 1, and performing solid-liquid separation to obtain secondary slag and secondary leaching liquid; returning the secondary leaching liquid to be used for primary acid leaching; neutralizing the primary leaching solution to remove impurities such as sulfate radical, iron, aluminum, radioactive substances, heavy metals and the like step by step, and then carrying out solid-liquid separation to obtain neutralization slag and rare earth solution. Although this patent document mentions that the neutralization and impurity removal can be performed to remove the impurities such as sulfate, iron, aluminum, etc. stepwise, this patent document is to remove the impurities such as iron, aluminum, etc. in the rare earth hydrochloride leaching solution, not the impurities such as iron and aluminum in the rare earth sulfate leaching solution. Moreover, the background art of this patent document explicitly states that: the rare earth hydrochloride leaching solution obtained by adopting the hydrochloric acid leaching process for the rare earth concentrate is generally neutralized and decontaminated by adopting sodium hydroxide and ammonia water, and part of sulfate ions, iron ions, aluminum ions, heavy metals and the like are removed, but the method for neutralizing and decontaminating the sodium hydroxide and the ammonia water is easy to cause rare earth loss, and the rare earth recovery rate is lower. In other words, the patent document tries to replace the traditional sodium hydroxide and ammonia water to neutralize and remove impurities in the rare earth hydrochloride leaching solution by adopting a new neutralization and impurity removal method so as to improve the rare earth recovery rate. Also, the patent document does not mention the contents of iron and aluminum in the obtained rare earth solution.
Disclosure of Invention
In view of the above, the present invention aims to provide a method for reducing the iron and aluminum content in a rare earth sulfate leaching solution. Compared with the traditional method for neutralizing and removing impurities from the rare earth sulfate leaching solution by adopting magnesium oxide, the method can further reduce the iron and aluminum content in the rare earth sulfate leaching solution.
The aim of the invention is realized by the following technical scheme.
The invention provides a method for reducing the content of iron and aluminum in rare earth sulfate leaching liquid, which comprises the following steps:
(1) Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element according to the flow rate of 0.6-2.7L/min to obtain a first mixed solution with the pH value of 3.1-3.6;
(2) Introducing the magnesia slurry into the first mixed solution according to the flow rate of 0.5-3.0L/min to obtain a second mixed solution with the pH value of 5.3-5.5;
(3) Reacting the second mixed solution for 1-3 h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution; wherein, fe is used in the rare earth sulfate solution 2 O 3 The content of iron element is less than 0.0015wt% calculated as Al 2 O 3 The content of the aluminum element is less than 0.01wt%.
According to the method for reducing the iron and aluminum content in the rare earth sulfate leaching solution, preferably, the pH value of the rare earth sulfate leaching solution is 1.3-1.8.
The method for reducing the iron and aluminum content in the rare earth sulfate leaching solution according to the invention is preferably that Fe is used in the rare earth sulfate leaching solution 2 O 3 The content of iron element is 1.27-1.57 wt% calculated by Al 2 O 3 The content of the calculated aluminum element is 3.25 to 3.31 weight percent.
According to the method for reducing the iron and aluminum content in the rare earth sulfate leaching solution, preferably, the flow rate of lime milk is 1.2-2.4L/min; the pH value of the first mixed solution is 3.5-3.6.
According to the method for reducing the iron and aluminum content of the rare earth sulfate leaching solution of the present invention, preferably, the lime milk is obtained by reacting quicklime with water in a ratio of 2.5 kg:15-25L.
According to the method for reducing the iron and aluminum content of the rare earth sulfate leaching solution of the present invention, preferably, the flow rate of the magnesium oxide slurry is 1.0 to 2.5L/min; the pH value of the second mixed solution is 5.3-5.4.
According to the method for reducing the iron and aluminum content of the rare earth sulfate leaching solution of the present invention, preferably, the magnesium oxide slurry is obtained by mixing magnesium oxide with water in a ratio of 1.2 kg:5-8L.
According to the method for reducing iron and aluminum contents in the rare earth sulfate leaching solution of the present invention, preferably, the magnesium oxide is added in an amount of 0.75 to 0.95kg based on 100L of the rare earth sulfate leaching solution.
According to the method for reducing the iron and aluminum content in the rare earth sulfate leaching solution of the present invention, preferably, the rare earth sulfate leaching solution is obtained by the steps of:
roasting the rare earth concentrate by adopting concentrated sulfuric acid and iron powder to obtain rare earth roasting ore containing sulfuric acid mixed rare earth and ferric pyrophosphate, leaching the rare earth roasting ore to obtain rare earth roasting ore slurry, and filtering the rare earth roasting ore slurry to obtain the rare earth sulfate leaching solution.
The method for reducing the iron and aluminum content in the rare earth sulfate leaching solution according to the invention is preferably carried out by using Fe in the rare earth sulfate solution 2 O 3 The content of iron element is less than or equal to 0.0012wt% calculated by Al 2 O 3 The content of aluminum element is less than or equal to 0.001wt%.
Compared with the traditional method of purely adopting magnesium oxide to neutralize and remove impurities from rare earth sulfate leaching solution, the method firstly adopts lime milk to be introduced and controls the flow rate and the dosage of the lime milk to obtain first mixed solution, the pH value of the first mixed solution is 3.1-3.6, then adopts magnesium oxide slurry to be introduced and controls the flow rate and the dosage of the magnesia slurry to obtain second mixed solution, the pH value of the second mixed solution is 5.3-5.5, thus the iron content in the rare earth sulfate leaching solution can be further reduced (to measure Fe 2 O 3 Expressed as content of (c) and aluminum content. In addition, compared with the traditional method for neutralizing and removing impurities by adopting magnesium oxide alone, the method provided by the invention has the advantages that the content of residual magnesium oxide in the rare earth sulfate solution is further reduced, and the production standard of enterprises can be met. The method is simple to operate and is suitable for industrial production.
Detailed Description
The present invention will be further described with reference to specific examples, but the scope of the present invention is not limited thereto.
The method for reducing the iron and aluminum content in the rare earth sulfate leaching solution comprises the following steps: 1) Introducing lime milk for reaction; 2) Introducing magnesium oxide slurry for reaction; 3) And obtaining the rare earth sulfate solution. In addition, a treatment step of neutralizing the slag may be included. The following is a detailed description.
< step of lime milk reaction passed in >
Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element according to the flow rate of 0.6-2.7L/min, and a first mixed solution with the pH value of 3.1-3.6 is obtained.
The rare earth sulfate leaching solution is obtained through the following steps: roasting the rare earth concentrate by adopting concentrated sulfuric acid and iron powder to obtain rare earth roasting ore containing sulfuric acid mixed rare earth and ferric pyrophosphate, leaching the rare earth roasting ore to obtain rare earth roasting ore slurry, and filtering the rare earth roasting ore slurry to obtain the rare earth sulfate leaching solution.
According to one embodiment of the invention, the obtaining of the rare earth sulphate leaching solution may comprise the steps of: mixing iron powder into the rare earth concentrate, stirring and fully mixing the materials by adopting concentrated sulfuric acid, roasting at high temperature to obtain rare earth roasting ore containing sulfuric acid mixed rare earth and ferric pyrophosphate, and leaching the rare earth roasting ore (reuse water can be adopted, specifically comprises the steps of supplementing clear water for the first time and using leaching slag washing water for the rest of water) to obtain rare earth roasting ore slurry, and filtering the rare earth roasting ore slurry to obtain rare earth sulfate leaching liquid and leaching slag; washing the leaching slag with water to obtain leaching slag washing water and washing slag. Specific reaction steps can be found in CN110042226a. And will not be described in detail herein.
The pH value of the rare earth sulfate leaching solution is 1.3-1.8, preferably 1.4-1.8, and more preferably 1.5-1.8. Thus, the method is beneficial to reducing the iron content and the aluminum content in the rare earth sulfate leaching solution.
In the rare earth sulfate leaching solution, fe is used as 2 O 3 The content of iron element is 1.27-1.57 wt% calculated by Al 2 O 3 The content of the calculated aluminum element is 3.25 to 3.31 weight percent. According to one embodiment of the invention, fe is used as Fe in the rare earth sulfate leaching solution 2 O 3 The content of iron element is 1.29 to 1.55 weight percent, calculated as Al 2 O 3 Aluminum element contentThe amount is 3.26 to 3.29 weight percent. In the present invention, the iron content is measured to determine the iron oxide (Fe 2 O 3 ) Expressed as the content of (c).
The lime milk is obtained by reacting quicklime with water, and the dosage ratio of the quicklime to the water is 2.5 kg:15-25L, preferably 2.5 kg:18-24L, and more preferably 2.5 kg:20-24L. This is advantageous in controlling the pH of the reaction solution. Compared with the traditional method of simply adopting magnesium oxide for neutralization and impurity removal, the method can further reduce the iron content and the aluminum content in the rare earth sulfate leaching solution, and is beneficial to realizing industrialization.
In the invention, the mixing mode of the rare earth sulfate leaching solution and the lime milk is preferably to continuously introduce the lime milk into the rare earth sulfate leaching solution. Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element, and stirring is carried out simultaneously. This is advantageous in controlling the pH of the reaction solution.
In the invention, the flow rate of the lime milk is 0.6-2.7L/min, preferably 1.2-2.4L/min, and more preferably 1.3-2.2L/min. The invention discovers that the lime milk is too fast to be introduced, the pH value is not easy to control, and when the pH value exceeds the range of the invention, a larger amount of slag can be generated and the rare earth content can be influenced. However, too slow the lime milk is introduced, the reaction time is prolonged, and the cost is increased.
In the present invention, the pH of the first mixed solution is controlled to be 3.1 to 3.6, preferably 3.3 to 3.6, more preferably 3.5 to 3.6. According to the invention, a great deal of researches and experiments show that the pH value is controlled to be 3.1-3.6 when lime milk is introduced, so that the following steps are achieved: compared with the traditional method of simply adopting magnesium oxide for neutralization and impurity removal, the method can further reduce the iron content and the aluminum content in the rare earth sulfate leaching solution.
In the present invention, the reaction temperature at the time of introducing lime milk may be 15 to 40 ℃, preferably 15 to 35 ℃, and more preferably 20 to 35 ℃.
< step of introducing magnesium oxide slurry reaction >
And (3) introducing the magnesium oxide slurry into the first mixed solution at a flow rate of 0.5-3.0L/min to obtain a second mixed solution with a pH value of 5.3-5.5.
The magnesium oxide slurry of the present invention is obtained by mixing magnesium oxide with water in an amount of 1.2 kg:5-8L, preferably 1.2 kg:5.5-7L, more preferably 1.2 kg:5.5-6.5L. Thus, the pH value of the reaction solution is beneficial to control, and compared with the traditional method of simply adopting magnesium oxide for neutralization and impurity removal, the method can further reduce the content of iron and aluminum in the rare earth sulfate leaching solution, and in addition, the content of residual magnesium oxide in the obtained rare earth sulfate solution is also obviously reduced.
In the present invention, the first mixed liquid and the magnesium oxide slurry are preferably mixed by continuously introducing the magnesium oxide slurry into the first mixed liquid. The magnesium oxide slurry was introduced into the first mixed solution while stirring.
The flow rate of the slurry for introducing the magnesium oxide is 0.5-3.0L/min, preferably 1.0-2.5L/min, and more preferably 1.2-2.5L/min. The invention finds that the magnesium oxide is added slowly, so that the flow rate of the magnesium oxide is not too fast, otherwise, the pH value is not easy to control. pH values outside the scope of the present invention also affect the total amount of rare earth and the quality of the immersion liquid.
In the present invention, the amount of magnesium oxide (solid) added is 0.75 to 0.95kg, preferably 0.8 to 0.9kg, more preferably 0.81 to 0.86kg, based on 100L of the rare earth sulfate leaching solution. The magnesium oxide slurry is introduced into the first mixed solution, and the pH value of the reaction solution is controlled to be 5.3-5.5, preferably 5.3-5.4. Too low a pH will not reduce the iron and aluminum content well and too high a pH will affect the total rare earth content and the quality of the immersion liquid.
< step of obtaining rare earth sulfate solution >
And (3) reacting the second mixed solution for 1-3 h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution.
The rare earth sulfate solution obtained by the invention uses Fe 2 O 3 The content of iron element is less than 0.0015wt% calculated as Al 2 O 3 The content of the aluminum element is less than 0.01wt%. Preferably, the rare earth sulfate solution is prepared by Fe 2 O 3 The content of iron element is less than or equal to 0.0012wt% calculated by Al 2 O 3 The content of aluminum element is 0.001wt% or less. Compared with the traditional method of leaching rare earth sulfate by using magnesium oxide onlyCompared with the neutralization and impurity removal of the liquid, the method can further reduce the iron content and the aluminum content in the rare earth sulfate leaching liquid. In addition, the residual magnesium oxide content in the obtained rare earth sulfate solution is also obviously reduced.
In the present invention, the second mixed solution is reacted for 1 to 3 hours, preferably 1 to 2 hours, more preferably 1 to 1.5 hours.
The solid-liquid separation method is not particularly limited, and it is preferable to filter the solid-liquid separation method by using a plate filter in industrial production.
The neutralization slag is washed by water, and the residual rare earth in the recycled slag can be recovered. According to one embodiment of the invention, the neutralization residue is mixed with water, and then solid-liquid separation is carried out to obtain a residue washing jellyfish solution and water washing residue; wherein the weight ratio of the neutralization slag to the water is 1:5.5-9, preferably the weight ratio of the neutralization slag to the water is 1:6-9, more preferably the weight ratio of the neutralization slag to the water is 1:6-8.
According to one embodiment of the invention, the method of the invention comprises in particular the following steps:
(1) Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element according to the flow rate of 0.6-2.7L/min to obtain a first mixed solution with the pH value of 3.1-3.6;
(2) Introducing the magnesia slurry into the first mixed solution according to the flow rate of 0.5-3.0L/min to obtain a second mixed solution with the pH value of 5.3-5.5;
(3) Reacting the second mixed solution for 1-3 h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution and neutralization residues; wherein, fe is used in the rare earth sulfate solution 2 O 3 The content of iron element is less than 0.0015wt% calculated as Al 2 O 3 The calculated aluminum element content is less than 0.01 weight percent;
(4) Mixing the neutralization slag with water, and then carrying out solid-liquid separation to obtain a slag washing jellyfish solution and water washing slag; wherein the weight ratio of the neutralization slag to the water is 1:5.5-9.
The inventor finds that the pH value of the first mixed solution is 3.1-3.6 by firstly introducing lime milk through a great deal of researches and experiments. And then, by controlling the flow rate and the dosage of the magnesium oxide to the pH value of the second mixed solution to be 5.3-5.5, non-rare earth impurities such as iron and aluminum in the rare earth sulfate leaching solution can be removed. The method can be realized by controlling the flow rate and the dosage of the lime milk and the flow rate and the dosage of the magnesia on the basis of the original process, is beneficial to industrial production and does not need to carry out large-scale reconstruction on equipment.
The test methods used in the examples and comparative examples are described below:
Fe 2 O 3 determination of the content: atomic absorption spectroscopy was used.
Al 2 O 3 Determination of the content: plasma spectroscopy is used.
Determination of MgO content: atomic absorption spectroscopy was used.
In the following examples and comparative examples:
the lime milk is prepared from 2.5t of quicklime and 20m 3 Calcium hydroxide suspension obtained by mixing the water of reaction. The magnesium oxide slurry is prepared from 1.2t of magnesium oxide and 6m of magnesium oxide 3 Is prepared by water preparation.
Preparation example 1
Fully mixing the rare earth concentrate, concentrated sulfuric acid and iron powder, continuously adding into a rotary kiln, and roasting at 600 ℃ to obtain rare earth roasting ore containing sulfuric acid mixed rare earth and ferric pyrophosphate. Leaching the rare earth roasting ore by water to obtain rare earth roasting ore slurry (REO is 30-40 g/L). And (3) filtering the rare earth roasting ore slurry mixture through a plate filter to obtain rare earth sulfate leaching liquid.
Comparative example 1
And (3) introducing the magnesium oxide slurry into the rare earth sulfate leaching solution containing the iron element and the aluminum element at the flow rate of 1.5L/min to obtain a mixed solution. Wherein,
and (3) reacting the mixed solution for 1h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution. The test results of the rare earth sulfate solution are shown in table 1.
Example 1 and comparative examples 2 to 6
Lime is added to the mixtureAnd introducing the milk into the rare earth sulfate leaching solution containing the iron element and the aluminum element according to the flow rate of 1.5L/min to obtain a first mixed solution. Wherein Fe is used as Fe in the rare earth sulfate leaching solution containing iron element and aluminum element 2 O 3 The content of iron element is A1, calculated as Al 2 O 3 The calculated aluminum element content is B1.
And (3) introducing the magnesium oxide slurry into the first mixed solution at a flow rate of 1.5L/min to obtain a second mixed solution.
And (3) reacting the second mixed solution for 1h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution. Wherein, fe is used in the rare earth sulfate solution 2 O 3 The content of iron element is A2, calculated as Al 2 O 3 The calculated aluminum element content is B2. The test results of the rare earth sulfate solution are shown in table 1.
TABLE 1
As is clear from comparison between example 1 and comparative example 1, compared with the conventional method of using magnesium oxide alone for neutralization and impurity removal, the method of the invention adopts lime milk to adjust the pH value of the rare earth sulfate aqueous solution to a specific range, and then uses magnesium oxide slurry to adjust the pH value, so that the content of iron and aluminum elements in the obtained rare earth sulfate solution is obviously reduced.
As is clear from a comparison of example 1 with comparative examples 2 to 6, the contents of iron and aluminum elements in the obtained rare earth sulfate solution can be reduced by controlling the pH values of the first mixed solution and the second mixed solution.
Comparative examples 7 to 8
The flow rate of lime milk or magnesia slurry was changed, and the other conditions were the same as in example 1, see table 2.
TABLE 2
As is evident from comparison of example 1 with comparative examples 7 to 8, by controlling the flow rate of lime milk or magnesia slurry, the iron and aluminum element contents in the obtained rare earth sulfate solution can be reduced.
TABLE 3 Table 3
| Numbering device | MgO (wt%) in sulfuric acid rare earth solution |
| Example 1 | 0.57 |
| Comparative example 1 | 1.35 |
As can be seen from Table 3, the rare earth sulfate solution obtained by the method of the present invention has a low residual magnesium oxide content.
The present invention is not limited to the above-described embodiments, and any modifications, improvements, substitutions, and the like, which may occur to those skilled in the art, fall within the scope of the present invention without departing from the spirit of the invention.
Claims (10)
1. A method for reducing the iron and aluminum content of a rare earth sulfate leach solution, comprising the steps of:
(1) Lime milk is introduced into rare earth sulfate leaching solution containing iron element and aluminum element according to the flow rate of 0.6-2.7L/min to obtain a first mixed solution with the pH value of 3.1-3.6;
(2) Introducing the magnesia slurry into the first mixed solution according to the flow rate of 0.5-3.0L/min to obtain a second mixed solution with the pH value of 5.3-5.5;
(3) Reacting the second mixed solution for 1-3 h, and then carrying out solid-liquid separation to obtain a rare earth sulfate solution; wherein, fe is used in the rare earth sulfate solution 2 O 3 The content of iron element is less than 0.0015wt% calculated as Al 2 O 3 The content of the aluminum element is less than 0.01wt%.
2. The method according to claim 1, wherein the pH of the rare earth sulphate leaching solution is between 1.3 and 1.8.
3. The method according to claim 1, wherein the rare earth sulfate leaching solution contains Fe 2 O 3 The content of iron element is 1.27-1.57 wt% calculated by Al 2 O 3 The content of the calculated aluminum element is 3.25 to 3.31 weight percent.
4. The method according to claim 1, characterized in that the flow rate of the lime milk is 1.2-2.4L/min; the pH value of the first mixed solution is 3.5-3.6.
5. The method according to claim 1, characterized in that the lime milk is obtained by reacting quicklime with water in a ratio of 2.5 kg:15-25L.
6. The method according to claim 1, wherein the flow rate of the magnesium oxide slurry is 1.0 to 2.5L/min; the pH value of the second mixed solution is 5.3-5.4.
7. The method according to claim 1, wherein the magnesium oxide slurry is obtained by mixing magnesium oxide with water in a ratio of 1.2 kg:5-8L.
8. The method according to claim 1, wherein the magnesium oxide is added in an amount of 0.75 to 0.95kg based on 100L of the rare earth sulfate leaching solution.
9. The method according to claim 1, characterized in that the rare earth sulphate leaching solution is obtained by the following steps:
roasting the rare earth concentrate by adopting concentrated sulfuric acid and iron powder to obtain rare earth roasting ore containing sulfuric acid mixed rare earth and ferric pyrophosphate, leaching the rare earth roasting ore to obtain rare earth roasting ore slurry, and filtering the rare earth roasting ore slurry to obtain the rare earth sulfate leaching solution.
10. The method according to any one of claims 1 to 9, wherein the rare earth sulphate solution is prepared as Fe 2 O 3 The content of iron element is less than or equal to 0.0012wt% calculated by Al 2 O 3 The content of aluminum element is less than or equal to 0.001wt%.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1721559A (en) * | 2004-12-15 | 2006-01-18 | 北京有色金属研究总院 | Process for comprehensive recovery of rare earth and thorium from rare earth ore |
| KR20080100137A (en) * | 2007-05-11 | 2008-11-14 | 에이지씨 세이미 케미칼 가부시키가이샤 | Method for recovering rare earth elements |
| CN101363079A (en) * | 2007-08-10 | 2009-02-11 | 有研稀土新材料股份有限公司 | Smelting method of iron rich mengite rare-earth mine |
| CN104328290A (en) * | 2013-07-22 | 2015-02-04 | 北京有色金属研究总院 | Ionic type rare-earth fine ore acid leaching process |
| CN105331812A (en) * | 2014-07-31 | 2016-02-17 | 有研稀土新材料股份有限公司 | Method for comprehensively recycling phosphorus and rare earth from rare earth phosphorite containing monazite |
| CN112301220A (en) * | 2020-10-30 | 2021-02-02 | 包头市聚峰稀土有限责任公司 | Method for reducing iron content in rare earth sulfate water leaching solution |
| CN113373326A (en) * | 2020-03-09 | 2021-09-10 | 有研稀土新材料股份有限公司 | Method for preparing pure rare earth sulfate solution |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU2008201945B2 (en) * | 2008-05-02 | 2014-03-06 | Arafura Resources Limited | Recovery of rare earth elements |
-
2022
- 2022-01-04 CN CN202210001436.7A patent/CN114293012B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1721559A (en) * | 2004-12-15 | 2006-01-18 | 北京有色金属研究总院 | Process for comprehensive recovery of rare earth and thorium from rare earth ore |
| KR20080100137A (en) * | 2007-05-11 | 2008-11-14 | 에이지씨 세이미 케미칼 가부시키가이샤 | Method for recovering rare earth elements |
| CN101363079A (en) * | 2007-08-10 | 2009-02-11 | 有研稀土新材料股份有限公司 | Smelting method of iron rich mengite rare-earth mine |
| CN104328290A (en) * | 2013-07-22 | 2015-02-04 | 北京有色金属研究总院 | Ionic type rare-earth fine ore acid leaching process |
| CN105331812A (en) * | 2014-07-31 | 2016-02-17 | 有研稀土新材料股份有限公司 | Method for comprehensively recycling phosphorus and rare earth from rare earth phosphorite containing monazite |
| CN113373326A (en) * | 2020-03-09 | 2021-09-10 | 有研稀土新材料股份有限公司 | Method for preparing pure rare earth sulfate solution |
| CN112301220A (en) * | 2020-10-30 | 2021-02-02 | 包头市聚峰稀土有限责任公司 | Method for reducing iron content in rare earth sulfate water leaching solution |
Non-Patent Citations (1)
| Title |
|---|
| 氧化钙沉淀硫酸稀土过程中杂质的分布与去除;孟祥龙;冯宗玉;黄小卫;董金诗;王良士;赵龙胜;;稀有金属(第10期);109-115 * |
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