CN104591247A - Method for fluorine recovery from bastnaesite by alkali pulp countercurrent washing - Google Patents
Method for fluorine recovery from bastnaesite by alkali pulp countercurrent washing Download PDFInfo
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- CN104591247A CN104591247A CN201510010478.7A CN201510010478A CN104591247A CN 104591247 A CN104591247 A CN 104591247A CN 201510010478 A CN201510010478 A CN 201510010478A CN 104591247 A CN104591247 A CN 104591247A
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- fluorine
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- hamartite
- alkali
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F7/00—Compounds of aluminium
- C01F7/48—Halides, with or without other cations besides aluminium
- C01F7/50—Fluorides
- C01F7/54—Double compounds containing both aluminium and alkali metals or alkaline-earth metals
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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Abstract
The invention discloses a method for fluorine recovery from bastnaesite by alkali pulp countercurrent washing. The method is carried out according to the following steps: (1) roasting bastnaesite to get roasted ore; (2) adding hydrochloric acid into roasted ore for leaching, filtering to get leaching residues; (3) adding saturated a sodium hydroxide liquid into the leaching residues for decomposition, thus obtaining alkali pulp; (4) mixing alkali pulp with water, performing three-to-ten level countercurrent washing for the obtained solid phase material, thus getting washing liquor and filtration residues; and (5) adding aluminum salt into the washing liquor, thus obtaining cryolite by evaporative concentration. The high-concentration alkali liquor and a fluoride liquid obtained through the method of the invention react with the aluminum salt to produce artificial cryolite; and water consumption is reduced greatly, water resource waste is reduced, fluorine recovery rate is very high, pollution to environment is lowered, and fluorine resource is saved.
Description
Technical field
The present invention relates to a kind of recovery method of fluorine, particularly the method for fluorine is reclaimed in the washing of a kind of hamartite alkali slurry adverse current.
Background technology
Fluorine is a kind of important Nonrenewable resources, and China's fluorite basic unit price is only 1/4 of the world, and workable reserve is only 1/10; Along with hamartite, fluorite mineral smelt the development of extraction industry, create a large amount of fluorine-containing wastes (being mainly fluoride waste) in industrial chain, cause the huge wasting of resources.How from waste, to extract high value added product, promote industrial chain and be worth the important directions that will be the following fluorine utilization of resources.
Hamartite production technique main is at present oxidizing roasting-Leaching in Hydrochloric Acid-sodium hydroxide decomposition method, and mineral need washing after the filter residue alkali that oxidizing roasting, Leaching in Hydrochloric Acid obtain turns, thus produce a large amount of fluoride wastes; For Sichuan Province, measure 20,000 tons by fluorine content 6% with ore deposit, the fluorine amount every year discharged to environment just can reach 0.12 ten thousand tons.
The water-washing method that tradition adopts is cross-flow washing, namely each washing all adds fresh wash water, the water of whole process need discharge alkali slurry quality 8 ~ 10 times, and except first step wash water can be used to salt such as recovery caustic soda and sodium phosphate etc., all the other wash waters directly discharge, not only cause huge discharge of wastewater, contaminate environment, also waste F resource.
The defluorination method of fluorinated water mainly contains absorption method, electrocoagulation, reverse osmosis method, ion exchange method, chemical precipitation method and coagulation sedimentation etc.; Application number be 201310015854.2 Chinese patent disclose a kind of de-fluoridation adsorbent and preparation method thereof, it is made primarily of ordinary Portland cement, water and Tai-Ace S 150, weight ratio between each raw material is 5:15:(3 ~ 4), this sorbent material to the saturated extent of adsorption of fluorine in water far above other sorbing material; Application number is the treatment process that the Chinese patent of 201310610111.X discloses a kind of high-concentration fluorine-containing waste water, by adding hydrochloric acid, lime, the stirring of PAC polymerize aluminum chloride successively, last sedimentation and filtration.These methods mainly pay close attention to the improvement after pollution except fluorine, although fluorine-containing trade effluent after treatment meets national sewage comprehensive emission standard, fluorine is not reclaimed as a kind of resource, economical effectiveness is undesirable.Application number be 201410116814.1 Chinese patent disclose the method for the fluorine-containing sludge recycling of a kind of fluoride wastewater treatment and generation thereof, fluoride waste and calcium chloride react adding under the slant acidity condition that spent acid acidic substance are formed by the method, in crystalline deposit removing waste water, most fluorion forms highly purified fluorine-containing sludge, fluorine-containing sludge adds in the reactor with whipping appts with excessive sulfuric acid after drying, at 150 ~ 300 DEG C, carry out reaction produce hydrogen fluoride, the thick hydrogen fluoride gas obtained obtains anhydrous hydrogen fluoride product by condensation, rectifying; This patent obtains hydrogen fluoride product by the fluorine in waste water, but flow process is longer, complex operation, and consumption amount of reagent is large.
Summary of the invention
For the problems referred to above that existing fluorinated water exists on recovery and utilization technology, the invention provides the method that fluorine is reclaimed in the washing of a kind of hamartite alkali slurry adverse current, by roasting, acidleach and caustic digestion, then adverse current washing, reclaim fluorine and obtain alkali lye, reducing the consumption of water simultaneously.
The method that fluorine is reclaimed in hamartite alkali slurry adverse current of the present invention washing is carried out according to the following steps:
1, by hamartite in 700 ~ 900 DEG C of roastings 1 ~ 2 hour, be cooled to normal temperature, obtain roasted ore;
2, in roasted ore, add the hydrochloric acid soln that concentration is 1 ~ 3mol/L, the weight adding hydrochloric acid soln is 10 ~ 20 times of roasted ore; Then leach 1 ~ 2 hour at 80 ~ 90 DEG C, filter and obtain leached mud;
3, in leached mud, add saturated sodium hydroxide solution decompose, the weight of saturated sodium hydroxide solution is 1.5 ~ 2 times of leached mud; Decomposition temperature 120 ± 5 DEG C, at least 60 minutes resolving times, obtains alkali slurry;
4, alkali slurry is mixed with water, filter the alkali lye that the liquid phase obtained is naoh concentration 1 ~ 2mol/L, the solid phase obtained adopts Multilevel rinse tank to carry out three to ten stage countercurrent washings, solid phase enters from the first step, wash water enters from final stage, form the countercurrent flow of solid phase and wash water and composite liberation step by step, every grade of washing time is 20 ~ 30 minutes, obtains washing lotion and filter residue;
5, in washing lotion, add aluminium salt to mix, add-on is 6 by the mol ratio of the aluminium in fluorion and aluminium salt, and then evaporation concentration obtains sodium aluminum fluoride.
The composition of above-mentioned hamartite is by weight percentage containing rare earth oxide (in REO) 30 ~ 70%, fluorine-containing 3 ~ 10%.
Above-mentioned aluminium salt is Aluminum chloride anhydrous.
In aforesaid method, the purity by weight of the sodium aluminum fluoride of acquisition is 90 ~ 99%.
In aforesaid method, the rate of recovery of fluorine reaches 95 ~ 99%.
The principal reaction that technical scheme of the present invention relates to has:
REFCO
3=REOF(CeOF)+CO
2↑；
3CeOF+1/2O
2=2CeO
2·CeF
3；
REF
3+3NaOH=RE(OH)
3+3NaF；
6NaF+AlCl
3=Na
3AlF
6↓+3NaCl。
Above-mentioned filter residue is mainly rare-earth hydroxide, as the raw material of further Extraction of rare earth element.
Compared with prior art, feature of the present invention and beneficial effect thereof are:
The present invention adopts adverse current water-washing method washing hamartite to decompose the alkali slurry obtained through oxidizing roasting, Leaching in Hydrochloric Acid and sodium hydroxide, obtain high-concentration alkali liquor and fluorine-containing solution, cryolith is obtained with after aluminium salt action, water loss compares traditional water-washing method great reduction, decrease the waste of water resources, the fluorine rate of recovery is very high, reduces the pollution to environment, has saved fluorine resource; The recovery of high concentration alkali solution simultaneously decreases chemical consumption and waste, be conducive to increasing economic efficiency, and water washing process rare earth elements only has insubstantial loss, the rare earth element in filter residue still operation routinely extracts, and does not have detrimentally affect to the utilization of rare earth element; The method of the invention is equally applicable to washing in using acid and alkali combination method, sodium hydroxide decomposition method process hamartite technique and removes the utilization of fluorine and fluoride waste.
Accompanying drawing explanation
Fig. 1 is the method flow schematic diagram of the hamartite alkali slurry adverse current washing recovery fluorine in the embodiment of the present invention 1;
Fig. 2 is the XRD figure of the sodium aluminum fluoride in the embodiment of the present invention 1.
Embodiment
Hydrochloric acid soln used in the present invention, sodium hydroxide solution and Aluminum chloride anhydrous are commercial analytical reagent.
In the embodiment of the present invention, the rate of recovery employing Shanghai essence scientific & technical corporation UV755B single beam ultraviolet-visible spectrophotometer of fluorine records in solution and is obtained by calculating after fluorinion concentration.
In the embodiment of the present invention, XRD figure is tested by Dutch PANalytical company X ' Pert Pro polycrystal X ray diffractometer and is obtained.
The hamartite adopted in the embodiment of the present invention is selected from the bastnaesite concentrate that Mianning County, Sichuan Province produces.
Embodiment 1
The composition of the hamartite adopted contains rare earth oxide 60%, fluorine 7% by weight percentage;
By hamartite in 700 DEG C of roastings 2 hours, be cooled to normal temperature, obtain roasted ore;
In roasted ore, add the hydrochloric acid soln that concentration is 1mol/L, the weight adding hydrochloric acid soln is 20 times of roasted ore; Then leach 2 hours at 80 DEG C, filter and obtain leached mud;
In leached mud, add saturated sodium hydroxide solution decompose, the weight of saturated sodium hydroxide solution is 1.5 times of leached mud; Decomposition temperature 120 ± 5 DEG C, 60 minutes resolving times, obtains alkali slurry;
Alkali slurry is mixed with water, filter the alkali lye that the liquid phase obtained is naoh concentration 1mol/L, the solid phase obtained adopts Multilevel rinse tank to carry out the washing of Pyatyi adverse current, solid phase enters from the first step, wash water enters from final stage, form the countercurrent flow of solid phase and wash water and composite liberation step by step, every grade of washing time is 20 minutes, obtains washing lotion and filter residue; Filter residue is mainly rare-earth hydroxide, as the raw material of further Extraction of rare earth element;
In washing lotion, add Aluminum chloride anhydrous mix, add-on is 6 by the mol ratio of the aluminium in fluorion and aluminium salt, and then evaporation concentration obtains sodium aluminum fluoride, and purity by weight is 99%, and X-ray diffraction result as shown in Figure 2; The rate of recovery of fluorine reaches 95%.
Embodiment 2
The composition of the hamartite adopted contains rare earth oxide 30%, fluorine 3% by weight percentage;
By hamartite in 800 DEG C of roastings 1.5 hours, be cooled to normal temperature, obtain roasted ore;
In roasted ore, add the hydrochloric acid soln that concentration is 2mol/L, the weight adding hydrochloric acid soln is 15 times of roasted ore; Then leach 1.5 hours at 85 DEG C, filter and obtain leached mud;
In leached mud, add saturated sodium hydroxide solution decompose, the weight of saturated sodium hydroxide solution is 1.8 times of leached mud; Decomposition temperature 120 ± 5 DEG C, 60 minutes resolving times, obtains alkali slurry;
Alkali slurry is mixed with water, filter the alkali lye that the liquid phase obtained is naoh concentration 1.5mol/L, the solid phase obtained adopts Multilevel rinse tank to carry out ten stage countercurrent washings, solid phase enters from the first step, wash water enters from final stage, form the countercurrent flow of solid phase and wash water and composite liberation step by step, every grade of washing time is 25 minutes, obtains washing lotion and filter residue; Filter residue is mainly rare-earth hydroxide, as the raw material of further Extraction of rare earth element;
In washing lotion, add Aluminum chloride anhydrous mix, add-on is 6 by the mol ratio of the aluminium in fluorion and aluminium salt, and then evaporation concentration obtains sodium aluminum fluoride, and purity by weight is 96%; The rate of recovery of fluorine reaches 97%.
Embodiment 3
The composition of the hamartite adopted contains rare earth oxide 70%, fluorine 10% by weight percentage;
By hamartite in 900 DEG C of roastings 1 hour, be cooled to normal temperature, obtain roasted ore;
In roasted ore, add the hydrochloric acid soln that concentration is 3mol/L, the weight adding hydrochloric acid soln is 10 times of roasted ore; Then leach 1 hour at 90 DEG C, filter and obtain leached mud;
In leached mud, add saturated sodium hydroxide solution decompose, the weight of saturated sodium hydroxide solution is 2 times of leached mud; Decomposition temperature 120 ± 5 DEG C, 90 minutes resolving times, obtains alkali slurry;
Alkali slurry is mixed with water, filter the alkali lye that the liquid phase obtained is naoh concentration 2mol/L, the solid phase obtained adopts Multilevel rinse tank to carry out three stage countercurrent washings, solid phase enters from the first step, wash water enters from final stage, form the countercurrent flow of solid phase and wash water and composite liberation step by step, every grade of washing time is 30 minutes, obtains washing lotion and filter residue; Filter residue is mainly rare-earth hydroxide, as the raw material of further Extraction of rare earth element;
In washing lotion, add Aluminum chloride anhydrous mix, add-on is 6 by the mol ratio of the aluminium in fluorion and aluminium salt, and then evaporation concentration obtains sodium aluminum fluoride, and purity by weight is 90%; The rate of recovery of fluorine reaches 99%.
Claims (5)
1. a method for fluorine is reclaimed in the washing of hamartite alkali slurry adverse current, it is characterized in that carrying out according to the following steps:
(1) by hamartite in 700 ~ 900 DEG C of roastings 1 ~ 2 hour, be cooled to normal temperature, obtain roasted ore;
(2) in roasted ore, add the hydrochloric acid soln that concentration is 1 ~ 3mol/L, the weight adding hydrochloric acid soln is 10 ~ 20 times of roasted ore; Then leach 1 ~ 2 hour at 80 ~ 90 DEG C, filter and obtain leached mud;
(3) in leached mud, add saturated sodium hydroxide solution decompose, the weight of saturated sodium hydroxide solution is 1.5 ~ 2 times of leached mud; Decomposition temperature 120 ± 5 DEG C, at least 60 minutes resolving times, obtains alkali slurry;
(4) alkali slurry is mixed with water, filter the alkali lye that the liquid phase obtained is naoh concentration 1 ~ 2mol/L, the solid phase obtained adopts Multilevel rinse tank to carry out three to ten stage countercurrent washings, solid phase enters from the first step, wash water enters from final stage, form the countercurrent flow of solid phase and wash water and composite liberation step by step, every grade of washing time is 20 ~ 30 minutes, obtains washing lotion and filter residue;
(5) in washing lotion, add aluminium salt to mix, add-on is 6 by the mol ratio of the aluminium in fluorion and aluminium salt, and then evaporation concentration obtains sodium aluminum fluoride.
2. the method for fluorine is reclaimed in a kind of hamartite alkali slurry adverse current according to claim 1 washing, it is characterized in that the composition of described hamartite is by weight percentage containing rare earth oxide 30 ~ 70%, fluorine-containing 3 ~ 10%.
3. the method for fluorine is reclaimed in a kind of hamartite alkali slurry adverse current according to claim 1 washing, it is characterized in that described aluminium salt is Aluminum chloride anhydrous.
4. the method for fluorine is reclaimed in a kind of hamartite alkali slurry adverse current according to claim 1 washing, it is characterized in that the purity by weight of the sodium aluminum fluoride obtained in described step (5) is 90 ~ 99%.
5. the method for fluorine is reclaimed in a kind of hamartite alkali slurry adverse current according to claim 1 washing, it is characterized in that the rate of recovery of fluorine reaches 95 ~ 99%.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105349786A (en) * | 2015-11-16 | 2016-02-24 | 多氟多化工股份有限公司 | Lithium-aluminum-contained electrolyte comprehensive recycling method |
| CN113667841A (en) * | 2021-07-14 | 2021-11-19 | 四川省冕宁县方兴稀土有限公司 | Method for extracting rare earth and recovering fluorine resource from bastnaesite |
| CN113800539A (en) * | 2021-08-18 | 2021-12-17 | 广西博世科环保科技股份有限公司 | Process for purifying and recovering salt in wet-process leaching solution of overhaul residues |
| CN114045405A (en) * | 2021-10-25 | 2022-02-15 | 四川江铜稀土有限责任公司 | Method for fixing fluorine in alkali-transferring slag during smelting separation of fluorine-carbon cerium rare earth ore |
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| CN102146512A (en) * | 2010-02-08 | 2011-08-10 | 北京有色金属研究总院 | Hamartite smelting separation process |
| CN102277484A (en) * | 2011-07-28 | 2011-12-14 | 内蒙古科技大学 | Method for separating and recovering sodium phosphate and sodium fluoride in mixed rare earth concentrate smelting process through alkaline method |
| CN102534269A (en) * | 2012-03-26 | 2012-07-04 | 乐山盛和稀土股份有限公司 | Method for comprehensively recycling various rare earth from rare earth materials containing fluorine |
| CN102653823A (en) * | 2012-05-25 | 2012-09-05 | 东北大学 | Method used for separating rare earth from bastnaesite sulphuric acid leach solution and preparing ice stone |
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2015
- 2015-01-09 CN CN201510010478.7A patent/CN104591247A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102146512A (en) * | 2010-02-08 | 2011-08-10 | 北京有色金属研究总院 | Hamartite smelting separation process |
| CN102277484A (en) * | 2011-07-28 | 2011-12-14 | 内蒙古科技大学 | Method for separating and recovering sodium phosphate and sodium fluoride in mixed rare earth concentrate smelting process through alkaline method |
| CN102534269A (en) * | 2012-03-26 | 2012-07-04 | 乐山盛和稀土股份有限公司 | Method for comprehensively recycling various rare earth from rare earth materials containing fluorine |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105349786A (en) * | 2015-11-16 | 2016-02-24 | 多氟多化工股份有限公司 | Lithium-aluminum-contained electrolyte comprehensive recycling method |
| CN105349786B (en) * | 2015-11-16 | 2017-07-14 | 多氟多化工股份有限公司 | A kind of method of the comprehensive reutilization of aluminium electrolyte containing lithium |
| CN113667841A (en) * | 2021-07-14 | 2021-11-19 | 四川省冕宁县方兴稀土有限公司 | Method for extracting rare earth and recovering fluorine resource from bastnaesite |
| CN113800539A (en) * | 2021-08-18 | 2021-12-17 | 广西博世科环保科技股份有限公司 | Process for purifying and recovering salt in wet-process leaching solution of overhaul residues |
| CN113800539B (en) * | 2021-08-18 | 2023-07-07 | 广西博世科环保科技股份有限公司 | Technology for purifying and recycling salt in wet leaching solution of overhaul slag |
| CN114045405A (en) * | 2021-10-25 | 2022-02-15 | 四川江铜稀土有限责任公司 | Method for fixing fluorine in alkali-transferring slag during smelting separation of fluorine-carbon cerium rare earth ore |
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Application publication date: 20150506 |